docs: shorten the README and correct how the tick is described

The README carried explanations that belong in AGENTS.md; it now follows the shape of the sibling node repositories and is a quarter shorter. The tick description was also wrong: it does not trigger a grab. Capture is free-running at ZED_FPS and a tick forwards the newest frame there is, so the tick sets the publish rate, and frames captured between two ticks are dropped. The usage snippet listed four of the five outputs, which read as an omission rather than the choice it is.
add typed Arrow payloads and a dora-image-view dataflow
2026-09-15 10:52:12 -05:00 · 2026-09-15 10:52:08 -05:00 · 2026-09-08 17:23:12 +00:00 · 2026-09-08 14:11:25 -03:00 · 2026-09-08 15:06:21 +00:00 · 2026-09-08 12:04:35 -03:00
33 changed files with 1634 additions and 1490 deletions
@@ -0,0 +1,50 @@
+# Two gates, neither of which needs a camera, the ZED SDK or CUDA: the dataflows
+# are checked against the typed contract in dora-node.yml without running the
+# node, and the payload packing is compiled and tested on its own.
+name: validate
+
+on: [push, pull_request]
+
+env:
+  DORA_VERSION: v1.0.1
+  DORA_TARGET: x86_64-unknown-linux-gnu
+
+jobs:
+  validate:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Install the dora CLI
+        run: |
+          curl -fsSL -o dora-cli.tar.gz \
+            "https://github.com/dora-rs/dora/releases/download/${DORA_VERSION}/dora-cli-${DORA_TARGET}.tar.gz"
+          tar xzf dora-cli.tar.gz
+          mkdir -p "$HOME/.local/bin"
+          install -m 755 "dora-cli-${DORA_TARGET}/dora" "$HOME/.local/bin/dora"
+          echo "$HOME/.local/bin" >> "$GITHUB_PATH"
+          rm -rf dora-cli.tar.gz "dora-cli-${DORA_TARGET}"
+
+      - run: dora --version
+
+      # strict_types: true in each dataflow turns a type warning into a
+      # non-zero exit, so a mismatched annotation fails here rather than at
+      # runtime. The viewer file is checked too: it wires the same outputs, and
+      # a rename that breaks only the consumer should still fail the build.
+      - name: Validate the dataflows
+        run: |
+          dora validate dataflow.yml
+          dora validate dataflow_view.yml
+
+  test:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Install uv
+        run: |
+          curl -LsSf https://astral.sh/uv/install.sh | sh
+          echo "$HOME/.local/bin" >> "$GITHUB_PATH"
+
+      - name: Test the payload packing
+        run: tests/run.sh
@@ -1,6 +1,7 @@
 build/
 bin/
 tmp/
-test/assets/*.png
-test/assets/*.jpg
-test/assets/*_result.*
+
+# dora build working directories
+git/
+out/
@@ -4,17 +4,29 @@ This file provides guidance to AI coding assistants when working with code in th

 ## What this is

-A dora-rs C++ node that interfaces with ZED stereo cameras. On each tick it grabs a frame, runs object detection, and publishes four outputs over the dora dataflow: a BGR image, an XYZRGBA point cloud, camera intrinsics, and detected objects with 3D positions. Camera management lives in `src/zed/`, detection engines in `src/engines/`, and the dora event loop in `src/main.cc`.
+A dora-rs C++ node that interfaces with ZED stereo cameras. Capture is free-running on its own thread at `ZED_FPS`; on each tick the event loop publishes the newest frame it has produced, or nothing if none arrived since the last tick. What goes out: a BGR image and a depth map every frame, camera intrinsics once per camera session, a camera state on every transition, and an XYZRGBA point cloud when `ZED_POINT_CLOUD` is on. Every payload is a typed Arrow array — the two frames as `std/media/v1/Image`, the rest as `std/core/v1/Float32` and `.../String` — which is what lets the node feed [dora-image-view](https://gitea.liria.cl/liria/dora-image-view) and anything else built against those types. Camera management lives in `src/zed/`, payload packing in `src/arrow/`, and the dora event loop in `src/main.cc`.
+
+The node is a camera source only. It ran inference in-process through `v0.1.0`, under `src/engines/`; that was removed so the node has no inference dependency and builds on any platform the ZED SDK supports. The removed code remains reachable at tag `v0.1.0`.
+
+## Test
+
+```bash
+tests/run.sh
+```
+
+Needs `g++` and `uv`; no camera, no ZED SDK, no CUDA.

 ## Build

 ```bash
-mkdir -p build && cd build && cmake .. && make install
+scripts/build.sh
 ```

-The binary is installed to `bin/dora_zed` relative to the repo root.
+The binary is installed to `bin/dora_zed` relative to the repo root. The script is also
+the dataflow's `build:` command: dora 1.0 executes build commands directly rather than
+through a shell, so `cd`, `&&` and command substitution do not work there.

-**Requirements:** CMake 3.21+, ZED SDK 5.x (at `/usr/local/zed`), CUDA Toolkit, ONNX Runtime 1.20+ (system install), Rust stable toolchain (for dora-rs C++ bindings).
+**Requirements:** dora 1.0+ (verified with `dora-cli 1.0.1`), CMake 3.21+, ZED SDK 5.x (at `/usr/local/zed`), CUDA Toolkit, Rust stable toolchain (for dora-rs C++ bindings).

 The first build clones dora-rs from GitHub and compiles `dora-node-api-cxx` via Cargo. This takes a while. Subsequent builds are incremental. If `DORA_ROOT_DIR` is set to a local dora checkout, it builds against that instead.

@@ -24,33 +36,36 @@ For a build without installing the SDK stack on the host, see the `Dockerfile` (

 ```bash
 dora up
-dora start dataflow.yml
+dora start dataflow.yml            # camera alone
+dora start dataflow_view.yml --uv  # camera plus dora-image-view
 ```

-Camera and detection behavior is configured entirely through environment variables (see README.md for the full list: `ZED_RESOLUTION`, `ZED_FPS`, `ZED_DEPTH_MODE`, `ZED_DETECTION_MODEL`, etc.).
+The two dataflows both declare the camera node, so run one at a time.
+
+Camera behavior is configured entirely through environment variables (see README.md for the full list: `ZED_RESOLUTION`, `ZED_FPS`, `ZED_DEPTH_MODE`, etc.).

 ## Architecture

 - **`src/util/env.h`** — Shared inline env-variable parsing helpers (`get_env_int`, `get_env_str`, `get_env_bool`, `get_env_float`).
- **`src/zed/camera.h`** — `zed::Config`, `zed::Calibration`, and `zed::Camera` class. Camera wraps the ZED SDK lifecycle: open (with retry loop), warmup, grab (image + point cloud), calibration, and close. Exposes `handle()` for engine access.
- **`src/zed/camera.cc`** — Implementation. SDK enum parsers live in an anonymous namespace.
- **`src/engines/engine.h`** — `engines::DetectedObject` struct and `engines::Engine` abstract base class (`enable`, `detect`, `objects`, `label_names`).
- **`src/engines/zed_native.h/cc`** — `engines::ZedNative`: wraps ZED SDK's TensorRT-optimized object detection module.
- **`src/engines/yolo_helpers.h`** — Header-only shared helpers used by the ONNX engine: `RawDetection`, `nms()`, `letterbox()`, `fuse_bbox()`, `backproject()`. Lives in `engines::detail` namespace.
- **`src/engines/yolo_onnx.h/cc`** — `engines::YoloOnnx` / `YoloOnnxConfig`: closed-vocabulary detection for any single-input YOLO ONNX model (YOLOv8, YOLOv11, YOLOv5, etc.). Auto-detects output layout (`NC_FIRST` / `NC_LAST` / `NC_LAST_OBJ`) from tensor shape; override with `ZED_ONNX_OUTPUT_FORMAT`. Labels loaded from `ZED_ONNX_LABELS` or `ZED_ONNX_LABELS_FILE`.
- **`src/main.cc`** — Dora event loop. Selects engine via `ZED_ENGINE` env var (`yolo_onnx`/`onnx` or `native`), holds a `std::unique_ptr<engines::Engine>`. Parses `ZED_PC_MODE` (`FULL`/`HALF`/`ROI`) once before the loop. On any input event (intended to be driven by a tick timer; the id is not inspected): calls `camera.grab()` and `detector->detect()`, then sends `image_bgr`, `point_cloud`, `camera_info`, and `objects` outputs. Point cloud output varies by mode: `FULL` sends the raw `sl::Mat` pointer (no copy); `HALF` downsamples by 2 in each dimension; `ROI` emits only valid points within detected bounding boxes as a flat `[N, 4]` array. Handles reconnection on grab failure.
+- **`src/zed/camera.h`** — `zed::Config`, `zed::Calibration`, and `zed::Camera` class. Camera wraps the ZED SDK lifecycle: `open()` (one attempt, returns success), warmup, grab (image + depth + point cloud), calibration, device timestamp, blank-frame check, `close()` and `reset()` (close plus `sl::Camera::reboot()` where the model allows it). Exposes `handle()` for engine access.
+- **`src/zed/capture.h/cc`** — `zed::Capture` and `zed::Frame`. Owns the camera on a dedicated thread: open, warmup, grab, blank/stall detection, backoff and escalation all live here, along with the packing of every payload into owned buffers. The newest frame is handed to the reader by swapping under a mutex (`take_frame`), which also recycles the previous frame's buffers so steady-state capture does not reallocate. **Nothing outside this file may call the ZED SDK** — it blocks unboundedly on a disconnected camera, which is what froze the node when the loop drove the camera directly.
+- **`src/zed/camera.cc`** — Implementation. SDK enum parsers live in an anonymous namespace. `parse_depth_mode` runs in `Config::from_env()`, not in the constructor, so an unrecognised `ZED_DEPTH_MODE` exits before the node joins the dataflow rather than falling back to a default.
+- **`src/arrow/array.h/cc`** — Builds the Arrow arrays the node publishes, against the Arrow C data interface: the two ABI structs are defined in the header rather than pulled from Arrow C++, which would be a heavy dependency for a producer that exports one array per output and never reads one. `image()` packs an `std/media/v1/Image` row, `float32()` and `string()` the primitive payloads. The payload bytes are **borrowed**, not copied — they only have to outlive the send, since dora IPC-encodes the array into shared memory inside `send_arrow_output` and then calls the release callbacks. Each node's release frees its children before itself, so releasing the root frees the tree.
+- **`src/main.cc`** — Dora event loop and output publishing only. On any input event (intended to be driven by a tick timer; the id is not inspected) it drains `take_state_change` and `take_frame` from the capture thread and publishes `image` and `depth`, plus `point_cloud` when `ZED_POINT_CLOUD` is on and `camera_info` on the first frame of a camera session (`camera_info_pending`, re-armed on reconnection). `send()` hands one `arrow_c::Exported` to `send_arrow_output`. `set_intrinsics` and `set_frame_stamps` stamp every output of a frame with the same intrinsics, `frame_id` and the two timestamps (`device_timestamp_ns`, `host_timestamp_ns`; both Unix-epoch nanoseconds); nothing about a frame's shape or encoding travels as metadata any more, since the Image struct carries it. The loop never touches the SDK. On exit it calls `capture.stop()` and waits 2 s for the thread; if the thread is still inside a blocking SDK call it gives up and `_Exit(0)`s rather than let dora time out and kill the node.
 - **`DoraTargets.cmake`** — Handles building or fetching dora-rs and generating the CXX bridge files. Two paths: local (`DORA_ROOT_DIR`) or git clone. Produces `dora_node_api_cxx` library and the `node_bridge.cc` glue.
- **`dataflow.yml`** — Example dora dataflow definition using the `git:` source format.
- **`Dockerfile`** — Ubuntu 24.04 x86-64 build environment (CUDA 12.8, ZED SDK 5.2, ONNX Runtime, Rust). No ARM64/Jetson image; build natively there. No camera needed; run the compile with `--gpus all`. Sets `NVIDIA_DRIVER_CAPABILITIES=compute,utility,video` — the `video` capability is what makes the container runtime mount NVDEC/NVENC, which `libsl_zed.so` links against. ONNX Runtime's CMake package files are relocated to `/usr/local/lib/cmake` because Ubuntu's multiarch CMake does not search `lib64`. Rust lives at `/usr/local/{rustup,cargo}` rather than `/root` so the build can run as the invoking user. `docker build -t dora-zed-build . && docker run --rm --gpus all --user "$(id -u):$(id -g)" -v "$PWD:/src" -v dora-zed-cargo:/usr/local/cargo/registry dora-zed-build`.
- **`scripts/export_yolo.py`** — PEP 723 uv script. Exports a standard YOLOv11 model to ONNX for closed-vocabulary detection. Run: `uv run scripts/export_yolo.py --model n --output-dir models/`.
- **`src/test_yolo_onnx.cc`** — Standalone C++ test binary (`bin/test_yolo_onnx`). Exercises `YoloOnnx` with an image (default `test/assets/yolo.png`). No dora and no live camera required. Uses the same env vars as the main binary. Saves an annotated result image alongside the input.
+- **`scripts/build.sh`** — Configure/compile/install in one shell-free-callable step. Referenced by both dataflows, the `Dockerfile` and the README.
+- **`dora-node.yml`** — Node manifest (`apiVersion: 1`): typed input/output contract, entrypoint, build command. `dora validate` injects these types into any dataflow that reaches the node by `path:`; a `git:`-sourced node does **not** pick it up, which is why both dataflows build from the checkout. `image` and `depth` are `std/media/v1/Image`; dora's compatibility graph has no edge from `std/core/v1/UInt8` to it, so a consumer declaring the struct rejects a producer declaring the buffer whatever it actually sends — the manifest has to move with the payload.
+- **`dataflow.yml`** — Example dora dataflow: the camera alone, no viewer and no Python dependency. Built from this checkout with `path:` + `build:` and `strict_types: true`. A consumer wires the node from a tag instead (see README) — dora 1.0 pins a source with the mutually exclusive `tag:`, `rev:` or `branch:`.
+- **`dataflow_view.yml`** — The same camera node plus [dora-image-view](https://gitea.liria.cl/liria/dora-image-view) on `image`, `depth` and `camera_info`, fetched from a tag. Run it with `--uv`, which gives the viewer its own managed environment. The viewer's manifest is not read at validate time (only a `path:` node's is), so the file repeats its contract in `input_types:` to get the two checked against each other. dora 1.0 has no cross-dataflow wiring (an input's `source` must resolve to a node in the same descriptor), so the camera node is duplicated here rather than referenced, and the two files are run one at a time.
+- **`tests/run.sh`** — Builds and runs the payload tests: `tests/arrow_test.cc` under `-fsanitize=address,undefined` (the release callbacks have to free the whole tree), and `tests/test_arrow.py`, which imports the exported arrays through pyarrow's C data interface and checks the values. `tests/arrow_export.cc` is the C shim the Python side calls. Covers `src/arrow` only, so it needs no camera, no ZED SDK and no dora.
+- **`.gitea/workflows/validate.yml`** — CI gates on push and pull request: `dora validate` on both dataflows, and `tests/run.sh`. Neither needs a camera, the ZED SDK or CUDA.
+- **`Dockerfile`** — Ubuntu 24.04 x86-64 build environment (CUDA 12.8, ZED SDK 5.2, Rust). No ARM64/Jetson image; build natively there. No camera needed; run the compile with `--gpus all`. Sets `NVIDIA_DRIVER_CAPABILITIES=compute,utility,video` — the `video` capability is what makes the container runtime mount NVDEC/NVENC, which `libsl_zed.so` links against. Rust lives at `/usr/local/{rustup,cargo}` rather than `/root` so the build can run as the invoking user. `docker build -t dora-zed-build . && docker run --rm --gpus all --user "$(id -u):$(id -g)" -v "$PWD:/src" -v dora-zed-cargo:/usr/local/cargo/registry dora-zed-build`.

 ## Key APIs

- **dora C++ API** (`<dora-node-api.h>`): `init_dora_node()`, `dora_node.events->next()`, `event_type()`, `send_output_with_metadata()`, `new_metadata()`.
- **ZED SDK** (`<sl/Camera.hpp>`): `sl::Camera`, `sl::InitParameters`, `sl::RuntimeParameters`, `sl::Mat`, `sl::ObjectDetectionParameters`, `sl::Objects`.
- **ONNX Runtime** (`<onnxruntime_cxx_api.h>`): `Ort::Env`, `Ort::Session`, `Ort::SessionOptions`, `Ort::Value`. Used by the `yolo_onnx` engine.
- Output data is sent as raw byte slices (`rust::Slice<const uint8_t>`) with typed metadata (shape, dtype, encoding).
+- **dora C++ API** (`<dora-node-api.h>`): `init_dora_node()`, `dora_node.events->next()`, `event_type()`, `send_arrow_output()`, `new_metadata()`.
+- **ZED SDK** (`<sl/Camera.hpp>`): `sl::Camera`, `sl::InitParameters`, `sl::RuntimeParameters`, `sl::Mat`.
+- Output data is sent as Arrow arrays: `send_arrow_output` takes an `ArrowArray`/`ArrowSchema` pair by pointer and moves both out, so a payload is built once with `src/arrow` and handed over.

 ## Tools

@@ -1,9 +1,15 @@
 cmake_minimum_required(VERSION 3.21)
-project(dora_zed VERSION 0.1.0 LANGUAGES C CXX)
+project(dora_zed VERSION 0.3.0 LANGUAGES C CXX)

 set(CMAKE_CXX_STANDARD 17)
 set(CMAKE_CXX_FLAGS "-fPIC")

+# DoraTargets.cmake picks the cargo profile from this, so an unset build type
+# would link debug dora bindings into an otherwise unoptimized binary.
+if(NOT CMAKE_BUILD_TYPE AND NOT CMAKE_CONFIGURATION_TYPES)
+    set(CMAKE_BUILD_TYPE Release CACHE STRING "Build type" FORCE)
+endif()
+
 include(DoraTargets.cmake)

 set(ZED_DIR "/usr/local/zed" CACHE PATH "Path to the ZED SDK")
@@ -13,18 +19,14 @@ find_package(zed REQUIRED)

 find_package(OpenCV REQUIRED)

-find_package(onnxruntime REQUIRED)
-set(ONNXRUNTIME_INCLUDE_DIRS "")  # propagated via imported target
-set(ONNXRUNTIME_LIBRARIES onnxruntime::onnxruntime)
-
 link_directories(${dora_link_dirs})
 link_directories(${ZED_LIBRARY_DIR})

 add_executable(dora_zed
    src/main.cc
+    src/arrow/array.cc
    src/zed/camera.cc
-    src/engines/zed_native.cc
-    src/engines/yolo_onnx.cc
+    src/zed/capture.cc
    ${node_bridge}
 )
 add_dependencies(dora_zed Dora_cxx)
@@ -38,29 +40,8 @@ target_include_directories(
        ${ZED_INCLUDE_DIRS}
        ${OpenCV_INCLUDE_DIRS}
        ${CUDAToolkit_INCLUDE_DIRS}
-        ${ONNXRUNTIME_INCLUDE_DIRS}
 )

-target_link_libraries(dora_zed dora_node_api_cxx ${ZED_LIBRARIES} ${OpenCV_LIBS} ${ONNXRUNTIME_LIBRARIES})
+target_link_libraries(dora_zed dora_node_api_cxx ${ZED_LIBRARIES} ${OpenCV_LIBS})

 install(TARGETS dora_zed DESTINATION ${CMAKE_CURRENT_SOURCE_DIR}/bin)
-
-# Standalone detector tests — no dora, no live camera required
-
-add_executable(test_yolo_onnx
-    src/test_yolo_onnx.cc
-    src/engines/yolo_onnx.cc
-)
-target_include_directories(test_yolo_onnx PRIVATE
-    ${CMAKE_CURRENT_SOURCE_DIR}/src
-    ${ZED_INCLUDE_DIRS}
-    ${OpenCV_INCLUDE_DIRS}
-    ${CUDAToolkit_INCLUDE_DIRS}
-    ${ONNXRUNTIME_INCLUDE_DIRS}
-)
-target_link_libraries(test_yolo_onnx PRIVATE
-    ${ZED_LIBRARIES}
-    ${OpenCV_LIBS}
-    ${ONNXRUNTIME_LIBRARIES}
-)
-install(TARGETS test_yolo_onnx DESTINATION ${CMAKE_CURRENT_SOURCE_DIR}/bin)
@@ -21,7 +21,6 @@
 FROM nvidia/cuda:12.8.1-devel-ubuntu24.04

 ARG ZED_VERSION=5.2
-ARG ORT_VERSION=1.24.4

 ENV DEBIAN_FRONTEND=noninteractive

@@ -51,25 +50,7 @@ RUN curl -fSL -o /tmp/ZED_SDK.run \
    && chmod -R a+rX /usr/local/zed \
    && rm -f /tmp/ZED_SDK.run

-# The tarball puts its CMake package files under lib/, but onnxruntimeTargets.cmake
-# resolves the library as <prefix>/lib64. Ubuntu is multiarch, so CMake does not
-# search lib64 for packages and ld.so does not search /usr/local/lib64 at all:
-# keep the libraries in lib64, move only the package files to lib/cmake, and add
-# lib64 to the linker path.
-RUN curl -fSL -o /tmp/ort.tgz \
-        "https://github.com/microsoft/onnxruntime/releases/download/v${ORT_VERSION}/onnxruntime-linux-x64-gpu-${ORT_VERSION}.tgz" \
-    && tar -xzf /tmp/ort.tgz -C /tmp \
-    && mkdir -p /usr/local/include/onnxruntime /usr/local/lib64 \
-    && cp -r /tmp/onnxruntime-linux-x64-gpu-${ORT_VERSION}/include/* /usr/local/include/onnxruntime/ \
-    && cp -r /tmp/onnxruntime-linux-x64-gpu-${ORT_VERSION}/lib/* /usr/local/lib64/ \
-    && mkdir -p /usr/local/lib/cmake \
-    && mv /usr/local/lib64/cmake/onnxruntime /usr/local/lib/cmake/ \
-    && rmdir /usr/local/lib64/cmake \
-    && echo /usr/local/lib64 > /etc/ld.so.conf.d/onnxruntime.conf \
-    && ldconfig \
-    && rm -rf /tmp/ort.tgz /tmp/onnxruntime-linux-x64-gpu-${ORT_VERSION}
-
 ENV NVIDIA_DRIVER_CAPABILITIES=compute,utility,video

 WORKDIR /src
-CMD ["bash", "-lc", "mkdir -p build && cd build && cmake .. && make -j$(nproc) install"]
+CMD ["scripts/build.sh"]
@@ -1,6 +1,8 @@
 # dora-zed

-Dora node for ZED stereo cameras. Publishes BGR images, point clouds, camera intrinsics, and 3D object detections.
+Dora node for ZED stereo cameras. On every tick it publishes a colour image and a depth
+map as `std/media/v1/Image`, plus camera intrinsics, a camera state, and an optional
+point cloud. A source for a vision pipeline: it takes a tick and produces frames.

 ## Usage

@@ -9,56 +11,169 @@ Add to your dataflow:
 ```yaml
 nodes:
  - id: zed-camera
-    git: ssh://git@gitea.liria.cl:5001/liria/dora-zed.git
-    git_checkout: v0.1.0
-    build: mkdir -p build && cd build && cmake .. && make install
+    git: https://gitea.liria.cl/liria/dora-zed.git
+    tag: v0.3.0
+    build: scripts/build.sh
    path: bin/dora_zed
    inputs:
      tick: dora/timer/millis/100
    outputs:
-      - image_bgr
+      - image
+      - depth
      - point_cloud
      - camera_info
-      - objects
+      - camera_state
 ```

-See [`dataflow.yml`](dataflow.yml) for a complete runnable example with a camera display node.
+The node is C++: building it needs the ZED SDK and CUDA on the machine that runs the
+dataflow — see [Build](#build). An output left out of `outputs:` is simply not published,
+so a dataflow that never turns the point cloud on can drop that line.

-## Dependencies
+### Runnable dataflows

-| Dependency | Version | Notes |
+| File | Contents | Run |
 |---|---|---|
-| [CMake](https://cmake.org/download/) | 3.21+ | |
-| [ZED SDK](https://www.stereolabs.com/developers/release) | 5.x | Bundles OpenCV; default path `/usr/local/zed` |
-| [CUDA Toolkit](https://developer.nvidia.com/cuda-downloads) | — | Required by ZED SDK |
-| [Rust toolchain](https://rustup.rs) | stable | Builds dora-rs C++ bindings |
-| [ONNX Runtime](https://github.com/microsoft/onnxruntime/releases) | 1.20+ | Required at configure time; used at runtime only by `yolo_onnx` |
+| [`dataflow.yml`](dataflow.yml) | The camera alone, no viewer and no Python dependency | `dora run dataflow.yml` |
+| [`dataflow_view.yml`](dataflow_view.yml) | The camera plus [dora-image-view][view] | `dora run dataflow_view.yml --uv` |

-### Installation scripts
+[view]: https://gitea.liria.cl/liria/dora-image-view

-| Platform | Script |
+`dataflow_view.yml` is the worked example of consuming this node: a window opens with
+the colour image and the depth map side by side, the camera model captioned across them.
+Press `q` to quit. It needs a display, and `--uv` so the viewer gets its own managed
+environment.
+
+dora has no cross-dataflow wiring, so both files declare the camera node themselves: run
+one at a time. Both build it from the checkout, which is what lets `dora validate` check
+them against [`dora-node.yml`](dora-node.yml) — the typed contract a consumer wires
+against, and what [CI](.gitea/workflows/validate.yml) validates on every push.
+
+## Inputs
+
+| Input | Description |
+|---|---|
+| `tick` | Publishes the newest frame captured since the last tick, or nothing. Wire to `dora/timer/millis/N`. |
+
+The tick does not drive the camera. Capture is free-running on its own thread, paced by
+the SDK to `ZED_FPS`, and each frame overwrites whatever the previous one left
+uncollected; a tick forwards the newest there is, and publishes nothing when none arrived
+since the last one. So the tick sets the publish rate, never the capture rate: below
+`ZED_FPS` it drops frames — the default 100 ms tick against the default 15 fps keeps two
+out of every three — and above it, the ticks that find nothing publish nothing.
+`dora/timer/millis/66` at 15 fps forwards every frame, each at most one capture period
+old and none of them twice.
+
+## Outputs
+
+| Output | Payload | Metadata |
+|---|---|---|
+| `image` | `std/media/v1/Image` struct, `bgr8` | intrinsics, `frame_id`, timestamps |
+| `depth` | `std/media/v1/Image` struct, `32FC1` | `units=mm`, intrinsics, `frame_id`, timestamps |
+| `camera_info` | `float32` `[fx, fy, cx, cy]` | `distortion`, `frame_id`, timestamps |
+| `point_cloud` | `float32` XYZRGBA, off by default | `shape`, `channels`, `units=mm`, intrinsics, timestamps |
+| `camera_state` | `string` | `host_timestamp_ns` |
+
+`image` and `depth` are both `std/media/v1/Image`: an Arrow struct of `width: UInt32`,
+`height: UInt32`, `encoding: Utf8` and `data: LargeBinary`. The payload describes itself,
+so nothing about its shape travels as message metadata. A depth map is an image whose
+pixels are distances, as ROS also treats it: `32FC1` is one float32 per pixel, `units`
+says what those floats measure, and `0` means missing depth — the payload contains no
+`inf` and no `nan`. `depth` is published on every frame `image` is, at the same size and
+`frame_id`.
+
+`camera_info` is published **once per camera session** — with the first frame after the
+camera opens, and again after a reconnection — since the intrinsics are fixed for a given
+camera and resolution. Every frame also carries `fx`, `fy`, `cx` and `cy` in its
+metadata, so a consumer that started after the camera did still ends up with them.
+
+Every output of a frame carries the same `frame_id` and both clocks as dora `timestamp`
+metadata: `device_timestamp_ns`, when the camera captured the frame, and
+`host_timestamp_ns`, when this node published it — both Unix-epoch nanoseconds. Two nodes
+reading the same frame agree on the device clock; the rest of the dataflow shares the
+host one.
+
+### Camera state
+
+`camera_state` lets a consumer tell a camera that has not delivered its first frame yet
+from one that has been lost:
+
+| State | Meaning |
+|---|---|
+| `opening` | The camera has not delivered a usable frame yet in this run |
+| `streaming` | Frames are being published |
+| `recovering` | The camera was streaming and has stopped; the node is bringing it back |
+
+The camera runs on its own thread, since the SDK can block indefinitely inside `grab()`
+and `open()` on a disconnected camera and would otherwise freeze the event loop. A camera
+that delivers no usable frame for 5 seconds is recovered, reopening on a 1, 2, 5 then 10
+second backoff and escalating to `sl::Camera::reboot()` past the first attempt; an
+all-black frame counts as a failed grab, since a camera whose link has dropped can keep
+reporting success while handing back a uniform one. Uncollected frames are dropped, so a
+consumer always gets the newest one.
+
+## Configuration
+
+Settings are environment variables, which a dataflow can carry per node, keeping them
+with the wiring rather than in whatever shell starts it:
+
+```yaml
+    env:
+      ZED_RESOLUTION: 720
+      ZED_FPS: 30
+```
+
+A node's `env:` wins over the environment the dataflow was started in; variables it does
+not set still pass through.
+
+| Variable | Default | Meaning |
+|---|---|---|
+| `ZED_RESOLUTION` | `1080` | `720`, `1080` or `2000` |
+| `ZED_FPS` | `15` | Frame rate |
+| `ZED_DEPTH_MODE` | `NEURAL` | `NEURAL`, `NEURAL_PLUS`, `NEURAL_LIGHT`, `PERFORMANCE`, `QUALITY` or `NONE`. An unrecognised value is a startup error, not a fallback. |
+| `ZED_DEPTH_MIN_MM` | `200` | Near end of the depth range, in millimetres |
+| `ZED_DEPTH_MAX_MM` | `600` | Far end of the depth range, in millimetres |
+| `ZED_CONFIDENCE_THRESHOLD` | `60` | Reject depth less certain than this (1–100, lower is stricter) |
+| `ZED_TEXTURE_CONFIDENCE_THRESHOLD` | `100` | Reject depth on surfaces less textured than this (1–100) |
+| `ZED_DEPTH_FILL` | `false` | Interpolate depth over holes. Overrides both confidence thresholds. |
+| `ZED_FLIP` | `ON` | `ON` or `OFF` |
+| `ZED_WARMUP_FRAMES` | `30` | Frames to discard on startup |
+| `ZED_POINT_CLOUD` | `false` | Retrieve and publish the point cloud |
+| `ZED_PC_MODE` | `FULL` | `FULL` is a `[H, W, 4]` grid; `HALF` is a stride-2 downsample. Only applies with `ZED_POINT_CLOUD` on. |
+
+The defaults match the reference camera driver the perception stack was tuned against, and
+the resolved depth settings are logged at startup.
+
+The point cloud is off because it is expensive: roughly 14.7 MB per frame at 1080p, paid
+in retrieval and in a copy whether or not anything consumes it. Consumers that need 3D
+back-project `depth` with the published intrinsics instead.
+
+## Build
+
+```bash
+scripts/build.sh
+```
+
+The binary is installed to `bin/dora_zed`. The script is also the dataflow's `build:`
+command, since dora 1.0 runs build commands directly rather than through a shell — `cd`
+and `&&` are not available there. The first build clones dora-rs and compiles its C++
+bindings with Cargo, which takes a while; later builds are incremental, and
+`DORA_ROOT_DIR` builds against a local dora checkout instead.
+
+**Requirements:** dora 1.0+ (verified with `dora-cli 1.0.1`), CMake 3.21+, ZED SDK 5.x at
+`/usr/local/zed` (it bundles OpenCV), the CUDA Toolkit it needs, and a stable Rust
+toolchain for the dora bindings.
+
+| Platform | Install the toolchain with |
 |---|---|
 | Ubuntu 24.04 x86_64 | `sudo scripts/install_linux_x64.sh` |
 | NVIDIA Jetson (ARM64) | `sudo scripts/install_linux_arm.sh` |
-| Windows x64 (PowerShell admin) | `scripts/install_windows.ps1` |
+| Windows x64 (PowerShell admin) | `scripts/install_windows.ps1`, plus the [ZED SDK][sdk] by hand |

-> **Jetson:** No official ONNX Runtime GPU binary for ARM64. It is still needed to configure the build; only the `yolo_onnx` engine uses it at runtime. Requires [building from source](https://onnxruntime.ai/docs/build/eps.html#tensorrt).
->
-> **Windows:** Install ZED SDK manually from [stereolabs.com](https://www.stereolabs.com/developers/release), then pass the ONNX Runtime path: `cmake .. -DCMAKE_PREFIX_PATH=C:\onnxruntime`
+[sdk]: https://www.stereolabs.com/developers/release

-## Local build
-
-```bash
-git clone ssh://git@gitea.liria.cl:5001/liria/dora-zed.git
-cd dora-zed
-mkdir -p build && cd build && cmake .. && make install
-```
-
-Binary installed to `bin/dora_zed`.
-
-### Containerized build
-
-[`Dockerfile`](Dockerfile) provides the full toolchain — CUDA, ZED SDK, ONNX Runtime and Rust — on Ubuntu 24.04, the newest release Stereolabs ships a ZED SDK for. No camera is needed.
+[`Dockerfile`](Dockerfile) carries the same toolchain on Ubuntu 24.04 — the newest release
+Stereolabs ships a ZED SDK for — so the host needs none of it, only an NVIDIA driver and
+the [NVIDIA Container Toolkit](https://docs.nvidia.com/datacenter/cloud-native/container-toolkit/latest/install-guide.html):

 ```bash
 docker build -t dora-zed-build .
@@ -66,126 +181,18 @@ docker run --rm --gpus all --user "$(id -u):$(id -g)" \
    -v "$PWD:/src" -v dora-zed-cargo:/usr/local/cargo/registry dora-zed-build
 ```

-The first run clones dora-rs and compiles it with Cargo; the named volume keeps that cache across runs.
-`--user` keeps `build/` and `bin/` owned by you rather than root.
+It runs the same `scripts/build.sh`. The named volume keeps the Cargo cache across runs
+and `--user` keeps `build/` and `bin/` owned by you. x86-64 only: on Jetson, run
+[`scripts/install_linux_arm.sh`](scripts/install_linux_arm.sh) and build natively.

-x86-64 only. On Jetson, run [`scripts/install_linux_arm.sh`](scripts/install_linux_arm.sh) on the
-device and build natively — there is no ARM64 image here.
-
-Needs an NVIDIA driver and the
-[NVIDIA Container Toolkit](https://docs.nvidia.com/datacenter/cloud-native/container-toolkit/latest/install-guide.html)
-on the host, as the ZED SDK does anyway. The image sets
-`NVIDIA_DRIVER_CAPABILITIES=compute,utility,video`: `libsl_zed.so` links against NVDEC
-(`libnvcuvid`) and NVENC (`libnvidia-encode`), which the container runtime mounts from the host
-only when `video` is in the capability list.
-
-## Configuration
-
-All behavior is controlled via environment variables.
-
-### Camera
-
-| Variable | Default | Description |
-|---|---|---|
-| `ZED_RESOLUTION` | `720` | `720`, `1080`, or `2000` |
-| `ZED_FPS` | `15` | Frame rate |
-| `ZED_DEPTH_MODE` | `NEURAL` | `PERFORMANCE`, `QUALITY`, `NEURAL`, or `NONE` |
-| `ZED_DEPTH_MIN_MM` | `10` | Minimum depth (mm) |
-| `ZED_DEPTH_MAX_MM` | `500` | Maximum depth (mm) |
-| `ZED_DEPTH_FILL` | `false` | Enable depth fill mode |
-| `ZED_FLIP` | `ON` | `ON` or `OFF` |
-| `ZED_WARMUP_FRAMES` | `30` | Frames to discard on startup |
-| `ZED_RETRY_INTERVAL_SECONDS` | `5` | Reconnection interval (s) |
-
-### Detection engine
-
-Set `ZED_ENGINE` to select the detection backend:
-
-| `ZED_ENGINE` | Custom model? | Classes |
-|---|---|---|
-| `native` (default) | No — ZED SDK built-in TensorRT | Fixed: 7 categories |
-| `yolo_onnx` (alias: `onnx`) | Yes — any single-input YOLO ONNX (v5/v8/v11) | Fixed labels from file or env var |
-
-#### `native` engine
-
-Uses ZED SDK's built-in TensorRT models — no model files to download or configure. `ZED_DETECTION_MODEL` selects the speed/accuracy variant, not a file path.
-
-Detects 7 fixed categories: PERSON, VEHICLE, BAG, ANIMAL, ELECTRONICS, FRUIT_VEGETABLE, SPORT.
-
-| Variable | Default | Description |
-|---|---|---|
-| `ZED_DETECTION_MODEL` | `MULTI_CLASS_BOX_MEDIUM` | `MULTI_CLASS_BOX_FAST`, `MULTI_CLASS_BOX_MEDIUM`, or `MULTI_CLASS_BOX_ACCURATE` |
-| `ZED_DETECTION_CONFIDENCE` | `40` | Confidence threshold (0–100) |
-| `ZED_DETECTION_TRACKING` | `false` | Enable object tracking |
-
-#### `yolo_onnx` engine (closed-vocabulary)
-
-For any single-input YOLO ONNX model with fixed class names (YOLOv8, YOLOv11, YOLOv5, custom-trained).
-
-Export a YOLOv11 model once:
+## Test

 ```bash
-uv run scripts/export_yolo.py --model n --output-dir models/
+tests/run.sh
 ```

-Then run:
-
-```bash
-ZED_ENGINE=yolo_onnx \
-ZED_ONNX_MODEL_PATH=models/yolo11n_i640.onnx \
-ZED_ONNX_LABELS_FILE=models/coco80.txt \
-dora start dataflow.yml
-```
-
-**Required:**
-
-| Variable | Description |
-|---|---|
-| `ZED_ONNX_MODEL_PATH` | Path to YOLO ONNX model |
-| `ZED_ONNX_LABELS` or `ZED_ONNX_LABELS_FILE` | Class names (inline CSV or one-per-line file) |
-
-**Optional:**
-
-| Variable | Default | Description |
-|---|---|---|
-| `ZED_ONNX_CONFIDENCE` | `0.25` | Confidence threshold (0.0–1.0) |
-| `ZED_ONNX_NMS_THRESHOLD` | `0.45` | NMS IoU threshold |
-| `ZED_ONNX_INPUT_SIZE` | `640` | Model input size (px) |
-| `ZED_ONNX_OUTPUT_FORMAT` | `auto` | Output layout: `auto`, `nc_first`/`yolov8`/`yolov11`, `nc_last`, `nc_last_obj`/`yolov5`. `auto` detects from tensor shape. |
-
-### Point cloud
-
-| `ZED_PC_MODE` | Shape | Description |
-|---|---|---|
-| `FULL` (default) | `[H, W, 4]` | Full resolution grid (~14.7 MB/frame at 720p) |
-| `HALF` | `[H/2, W/2, 4]` | Stride-2 downsample (~4× smaller) |
-| `ROI` | `[N, 4]` | Valid points within detected bounding boxes only |
-
-## Inputs
-
-| Input | Description |
-|---|---|
-| `tick` | Triggers a camera grab and detection. Connect to `dora/timer/millis/N`. |
-
-## Outputs
-
-| Output | Type | Description |
-|---|---|---|
-| `image_bgr` | `uint8 [H, W, 3]` | BGR image. Metadata: `shape`, `encoding=bgr8`, intrinsics, `timestamp_ns`. |
-| `point_cloud` | `float32 [*, 4]` | XYZRGBA point cloud. Shape depends on `ZED_PC_MODE`. Metadata: `units=mm`, intrinsics. |
-| `camera_info` | `float32 [4]` | `[fx, fy, cx, cy]`. Metadata: `distortion` coefficients. |
-| `objects` | `float32 [N, 37]` | Detected objects. See below. |
-
-### `objects` layout
-
-Each of the N rows contains 37 floats:
-
-| Index | Field | Description |
-|---|---|---|
-| 0 | `label_id` | Class index |
-| 1 | `confidence` | Score (0–100) |
-| 2–4 | `x, y, z` | 3D center (mm) |
-| 5–12 | `bb2d` | 2D bounding box: 4 corners × (x, y) px |
-| 13–36 | `bb3d` | 3D bounding box: 8 corners × (x, y, z) mm |
-
-Metadata includes `engine`, `label_names`, `image_width`, `image_height`, and `timestamp_ns`. An empty array `[0, 37]` is sent when no objects are detected.
+Unit tests over `src/arrow`, which packs every payload this node sends: each exported
+Arrow array is round-tripped through pyarrow to check what a consumer reads back, and
+built again under the sanitizers to check that releasing one frees it. They need neither a
+camera, the ZED SDK nor dora, which is what lets CI run them; everything past the packing
+is covered by running a dataflow against a real camera.
@@ -1,18 +1,20 @@
+# The repository's own example: builds and runs the node from this checkout, so
+# `dora validate` picks up the typed contract in dora-node.yml next to it.
+# A consumer wires the node from a tag instead — see README.md.
+#
+# The camera alone, with no viewer and no Python dependency. For a run that
+# also displays the stream, use dataflow_view.yml.
+strict_types: true
+
 nodes:
  - id: zed-camera
-    git: ssh://git@gitea.liria.cl:5001/liria/dora-zed.git
-    git_checkout: v0.1.0
-    build: mkdir -p build && cd build && cmake .. && make install
    path: bin/dora_zed
+    build: scripts/build.sh
    inputs:
      tick: dora/timer/millis/100
    outputs:
-      - image_bgr
-      - objects
-
-  - id: plot
-    git: https://github.com/dora-rs/dora-hub.git
-    build: pip install ./node-hub/opencv-plot
-    path: opencv-plot
-    inputs:
-      image: zed-camera/image_bgr
+      - image
+      - depth
+      - point_cloud
+      - camera_info
+      - camera_state
@@ -0,0 +1,46 @@
+# The camera into dora-image-view, and the worked example of wiring this node to
+# a consumer.
+#
+# dora has no cross-dataflow wiring, so the camera node is declared here too
+# rather than referenced — run this file or dataflow.yml, not both.
+#
+# Run it with `--uv`, which gives the viewer its own managed environment:
+#
+#     dora run dataflow_view.yml --uv
+#
+# Fetching the viewer needs anonymous read access to its repository. dora-cli
+# 1.0.1 fetches through libgit2 with no credential callback, so ssh:// cannot
+# authenticate at all; on Gitea, marking the repository public is not enough
+# either, since a repository inside a private organization answers an anonymous
+# clone with 401.
+strict_types: true
+
+nodes:
+  - id: zed-camera
+    path: bin/dora_zed
+    build: scripts/build.sh
+    inputs:
+      tick: dora/timer/millis/100
+    outputs:
+      - image
+      - depth
+      - point_cloud
+      - camera_info
+      - camera_state
+
+  - id: view
+    git: https://gitea.liria.cl/liria/dora-image-view.git
+    tag: v0.1.0
+    build: uv pip install .
+    path: dora-image-view
+    inputs:
+      image: zed-camera/image
+      depth: zed-camera/depth
+      camera_info: zed-camera/camera_info
+    # The viewer's own manifest says this, but a `git:` node's manifest is not
+    # read at validate time — only at build. Repeating it here is what makes the
+    # two contracts checked against each other now rather than at runtime.
+    input_types:
+      image: std/media/v1/Image
+      depth: std/media/v1/Image
+      camera_info: std/core/v1/Float32
@@ -0,0 +1,66 @@
+# Node manifest: the typed contract a consumer wires against.
+#
+# No source package is shared between node repositories, so this file and its
+# type URNs are the only contract a consumer has. `dora validate` checks a
+# dataflow against it without running the node, so CI needs no camera and no
+# ZED SDK.
+apiVersion: 1
+name: dora-zed
+namespace: liria
+description: ZED stereo camera source publishing an image, a depth map, intrinsics and an optional point cloud
+categories: [sensor]
+keywords: [zed, stereolabs, camera, depth, stereo, jetson]
+
+runtime: cpp
+entrypoint: bin/dora_zed
+build: scripts/build.sh
+dora: ">=1.0"
+
+inputs:
+  tick:
+    type: std/core/v1/UInt64
+    required: true
+    description: >-
+      Publishes the newest frame the capture thread has grabbed, or nothing if
+      none arrived since the last tick. It does not drive the camera: capture is
+      free-running at ZED_FPS, so this sets the publish rate and anything
+      captured between two ticks is dropped. Connect to dora/timer/millis/N.
+
+outputs:
+  image:
+    type: std/media/v1/Image
+    description: >-
+      Captured frame as an Arrow struct {width, height, encoding, data}. The
+      encoding is always bgr8, three bytes per pixel.
+  depth:
+    type: std/media/v1/Image
+    description: >-
+      Depth map as an Arrow struct {width, height, encoding, data}, one channel
+      per pixel -- dora has no depth type, and a depth map is an image whose
+      pixels are distances, which is how ROS spells it too. The encoding is
+      32FC1 and the `units` metadata is mm. Missing depth is 0, never inf or
+      nan.
+  camera_info:
+    type: std/core/v1/Float32
+    description: Intrinsics [fx, fy, cx, cy], distortion in the metadata. Published once per camera session.
+  point_cloud:
+    type: std/core/v1/Float32
+    description: XYZRGBA point cloud, shape in the metadata. Published only when ZED_POINT_CLOUD is on.
+  camera_state:
+    type: std/core/v1/String
+    description: One of opening, streaming, recovering. Published on every change.
+
+example: |
+  - id: zed-camera
+    git: https://gitea.liria.cl/liria/dora-zed.git
+    tag: v0.3.0
+    build: scripts/build.sh
+    path: bin/dora_zed
+    inputs:
+      tick: dora/timer/millis/100
+    outputs:
+      - image
+      - depth
+      - point_cloud
+      - camera_info
+      - camera_state
@@ -0,0 +1,14 @@
+#!/usr/bin/env bash
+# Configure, compile and install the node into bin/.
+#
+# dora 1.0 runs a node's `build:` command directly rather than through a shell,
+# so `cd`, `&&` and command substitution are not available there. The whole
+# sequence lives here instead, and the dataflow only invokes this script.
+set -euo pipefail
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+REPO_DIR="$(dirname "$SCRIPT_DIR")"
+BUILD_DIR="${REPO_DIR}/build"
+
+cmake -S "$REPO_DIR" -B "$BUILD_DIR" -DCMAKE_BUILD_TYPE=Release
+cmake --build "$BUILD_DIR" --target install --parallel "$(nproc)"
@@ -1,111 +0,0 @@
-# /// script
-# requires-python = ">=3.10"
-# dependencies = ["ultralytics>=8.3"]
-# ///
-"""Export a standard YOLOv11 model to ONNX for closed-vocabulary detection.
-
-The exported model has one input:
-  images  (1, 3, imgsz, imgsz)  float32
-
-Class names are fixed at training time. Provide them at runtime via
-ZED_ONNX_LABELS or ZED_ONNX_LABELS_FILE.
-
-Usage:
-    uv run scripts/export_yolo.py
-    uv run scripts/export_yolo.py --model s --output-dir models/
-    uv run scripts/export_yolo.py --model m --imgsz 1280
-"""
-
-import argparse
-import shutil
-import sys
-from pathlib import Path
-
-MODELS = {
-    "n": "yolo11n",
-    "s": "yolo11s",
-    "m": "yolo11m",
-    "l": "yolo11l",
-    "x": "yolo11x",
-}
-
-
-def parse_args():
-    p = argparse.ArgumentParser(
-        description="Export YOLOv11 to ONNX for closed-vocabulary detection"
-    )
-    p.add_argument(
-        "--model", "-m",
-        choices=list(MODELS),
-        default="n",
-        help="Model size: n (~6 MB), s (~18 MB), m (~38 MB), l (~49 MB), x (~109 MB). Default: n",
-    )
-    p.add_argument(
-        "--imgsz",
-        type=int,
-        default=640,
-        help="Input image size in pixels (square). Default: 640",
-    )
-    p.add_argument(
-        "--output-dir", "-o",
-        default=".",
-        help="Output directory for the .onnx file. Default: current directory",
-    )
-    return p.parse_args()
-
-
-def verify_output(onnx_path: Path):
-    try:
-        import onnx
-        model = onnx.load(str(onnx_path))
-        inputs  = [(i.name, [d.dim_value for d in i.type.tensor_type.shape.dim])
-                   for i in model.graph.input]
-        outputs = [(o.name, [d.dim_value for d in o.type.tensor_type.shape.dim])
-                   for o in model.graph.output]
-        print(f"  Inputs:  {inputs}")
-        print(f"  Outputs: {outputs}")
-    except ImportError:
-        print("  (install 'onnx' to verify model structure)")
-
-
-def main():
-    args = parse_args()
-
-    try:
-        from ultralytics import YOLO
-    except ImportError:
-        print("Error: ultralytics not installed. Run: uv run scripts/export_yolo.py", file=sys.stderr)
-        sys.exit(1)
-
-    model_name = MODELS[args.model]
-    out_dir = Path(args.output_dir)
-    out_dir.mkdir(parents=True, exist_ok=True)
-    out_name = f"{model_name}_i{args.imgsz}.onnx"
-    dst = out_dir / out_name
-
-    print(f"Model:      {model_name}.pt")
-    print(f"Input size: {args.imgsz}")
-    print(f"Output:     {dst}")
-    print()
-
-    model = YOLO(f"{model_name}.pt")
-    exported = Path(model.export(format="onnx", imgsz=args.imgsz))
-
-    if exported.resolve() != dst.resolve():
-        shutil.move(str(exported), str(dst))
-
-    print(f"\nVerifying exported model...")
-    verify_output(dst)
-
-    print(f"\nExported: {dst.resolve()}")
-    print(f"\nRun with (COCO labels example):")
-    print(f"  ZED_ENGINE=onnx \\")
-    print(f"  ZED_ONNX_MODEL_PATH={dst.resolve()} \\")
-    print(f"  ZED_ONNX_LABELS_FILE=models/coco80.txt \\")
-    print(f"  dora start dataflow.yml")
-    print(f"\nOr with inline labels:")
-    print(f"  ZED_ONNX_LABELS=\"person,car,chair\" \\")
-
-
-if __name__ == "__main__":
-    main()
@@ -9,11 +9,6 @@
 #   JetPack 6.2.2   (L4T 36.5)
 #   JetPack 7.0     (L4T 38.2) — Jetson Thor
 #   JetPack 7.1     (L4T 38.4)
-#
-# ONNX Runtime: Microsoft does not publish official GPU binaries for ARM64.
-#   ONNX Runtime is still needed to configure the build; only the yolo_onnx
-#   engine uses it at runtime. Build it from source:
-#   https://onnxruntime.ai/docs/build/eps.html#tensorrt
 set -euo pipefail

 ZED_VERSION="5.2"
@@ -63,13 +58,5 @@ else
    sudo "${TMP_DIR}/ZED_SDK.run" -- silent skip_python skip_tools
 fi

-# --- ONNX Runtime ---
-echo ""
-echo ">>> ONNX Runtime (ARM64 GPU): no official pre-built binary available."
-echo "    Needed to configure the build; only yolo_onnx uses it at runtime."
-echo "    Build from source:"
-echo "      https://onnxruntime.ai/docs/build/eps.html#tensorrt"
-echo ""
-
-echo ">>> Done. You can now run: mkdir -p build && cd build && cmake .. && make install"
+echo ">>> Done. You can now run: scripts/build.sh"
 echo ">>> Downloaded files are in ${TMP_DIR}"
@@ -6,7 +6,6 @@
 set -euo pipefail

 ZED_VERSION="5.2"
-ORT_VERSION="1.24.4"

 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 TMP_DIR="${SCRIPT_DIR}/../tmp"
@@ -34,32 +33,5 @@ else
    sudo "${TMP_DIR}/ZED_SDK.run" -- silent skip_python skip_tools
 fi

-# --- ONNX Runtime (C++ GPU, installs to /usr/local) ---
-if [ -f /usr/local/lib64/libonnxruntime.so ] && [ -d /usr/local/lib/cmake/onnxruntime ]; then
-    echo ">>> ONNX Runtime already installed — skipping."
-else
-    echo ">>> Downloading ONNX Runtime ${ORT_VERSION} GPU..."
-    download \
-        "https://github.com/microsoft/onnxruntime/releases/download/v${ORT_VERSION}/onnxruntime-linux-x64-gpu-${ORT_VERSION}.tgz" \
-        "${TMP_DIR}/onnxruntime-linux-x64-gpu-${ORT_VERSION}.tgz"
-    echo ">>> Extracting..."
-    tar -xzf "${TMP_DIR}/onnxruntime-linux-x64-gpu-${ORT_VERSION}.tgz" -C "${TMP_DIR}"
-    echo ">>> Installing ONNX Runtime to /usr/local..."
-    sudo mkdir -p /usr/local/include/onnxruntime
-    sudo cp -r "${TMP_DIR}/onnxruntime-linux-x64-gpu-${ORT_VERSION}/include/"* /usr/local/include/onnxruntime/
-    sudo mkdir -p /usr/local/lib64
-    sudo cp -r "${TMP_DIR}/onnxruntime-linux-x64-gpu-${ORT_VERSION}/lib/"* /usr/local/lib64/
-    # onnxruntimeTargets.cmake resolves the library as <prefix>/lib64, but Ubuntu
-    # is multiarch: CMake does not search lib64 for packages and ld.so does not
-    # search /usr/local/lib64 at all. Move only the package files to lib/cmake
-    # and put lib64 on the linker path.
-    sudo mkdir -p /usr/local/lib/cmake
-    sudo rm -rf /usr/local/lib/cmake/onnxruntime
-    sudo mv /usr/local/lib64/cmake/onnxruntime /usr/local/lib/cmake/
-    sudo rmdir /usr/local/lib64/cmake
-    echo /usr/local/lib64 | sudo tee /etc/ld.so.conf.d/onnxruntime.conf > /dev/null
-    sudo ldconfig
-fi
-
-echo ">>> Done. You can now run: mkdir -p build && cd build && cmake .. && make install"
+echo ">>> Done. You can now run: scripts/build.sh"
 echo ">>> Downloaded files are in ${TMP_DIR}"
@@ -10,10 +10,6 @@
 $ErrorActionPreference = "Stop"

 $ZED_INSTALL_DIR = "C:\Program Files (x86)\ZED SDK"
-$ORT_VERSION     = "1.24.4"
-$ORT_NAME        = "onnxruntime-win-x64-gpu_cuda13-$ORT_VERSION"
-$ORT_URL         = "https://github.com/microsoft/onnxruntime/releases/download/v$ORT_VERSION/$ORT_NAME.zip"
-$ORT_DEST        = "C:\onnxruntime"

 # --- ZED SDK ---
 if (Test-Path $ZED_INSTALL_DIR) {
@@ -25,23 +21,5 @@ if (Test-Path $ZED_INSTALL_DIR) {
    Write-Host ""
 }

-# --- ONNX Runtime ---
-if (Test-Path "$ORT_DEST\lib\onnxruntime.dll") {
-    Write-Host ">>> ONNX Runtime already installed at '$ORT_DEST' — skipping."
-} else {
-    Write-Host ">>> Downloading ONNX Runtime $ORT_VERSION GPU (CUDA 13)..."
-    $tmp = "$env:TEMP\$ORT_NAME.zip"
-    Invoke-WebRequest -Uri $ORT_URL -OutFile $tmp
-
-    Write-Host ">>> Extracting to $ORT_DEST..."
-    Expand-Archive -Path $tmp -DestinationPath $env:TEMP -Force
-    if (Test-Path $ORT_DEST) { Remove-Item $ORT_DEST -Recurse -Force }
-    Move-Item "$env:TEMP\$ORT_NAME" $ORT_DEST
-    Remove-Item $tmp
-
-    Write-Host ">>> ONNX Runtime installed to $ORT_DEST"
-    Write-Host "    Pass it to CMake: cmake .. -DCMAKE_PREFIX_PATH=C:\onnxruntime"
-}
-
 Write-Host ""
 Write-Host ">>> Done."
@@ -0,0 +1,179 @@
+#include "arrow/array.h"
+
+#include <cstring>
+#include <string>
+#include <utility>
+#include <vector>
+
+namespace arrow_c {
+namespace {
+
+// Producer-owned storage for one schema node. The struct's `format`, `name` and
+// `children` pointers point in here, which is why it outlives the call that
+// built it and is freed by the release callback rather than by the builder.
+struct SchemaData {
+    std::string format;
+    std::string name;
+    std::vector<ArrowSchema*> children;
+};
+
+// Producer-owned storage for one array node. `owned` holds the bytes this
+// node's own buffers point into - offset arrays, and scalars that have no
+// storage elsewhere. The payload itself is borrowed from the caller.
+struct ArrayData {
+    std::vector<uint8_t> owned;
+    std::vector<const void*> buffers;
+    std::vector<ArrowArray*> children;
+};
+
+// A node's release callback releases its children before freeing itself, so a
+// consumer that only releases the root - which is all the interface requires -
+// still frees the whole tree.
+void release_schema(ArrowSchema* schema) {
+    auto* data = static_cast<SchemaData*>(schema->private_data);
+
+    for (ArrowSchema* child : data->children) {
+        if (child->release != nullptr) {
+            child->release(child);
+        }
+        delete child;
+    }
+
+    delete data;
+    schema->release = nullptr;
+}
+
+void release_array(ArrowArray* array) {
+    auto* data = static_cast<ArrayData*>(array->private_data);
+
+    for (ArrowArray* child : data->children) {
+        if (child->release != nullptr) {
+            child->release(child);
+        }
+        delete child;
+    }
+
+    delete data;
+    array->release = nullptr;
+}
+
+void set_schema(ArrowSchema& schema, const char* format, const char* name,
+                std::vector<ArrowSchema*> children) {
+    auto* data = new SchemaData{format, name, std::move(children)};
+
+    schema.format = data->format.c_str();
+    schema.name = data->name.c_str();
+    schema.metadata = nullptr;
+    // Nullable everywhere, which is what pyarrow's defaults produce: the same
+    // struct built by a Python node has to compare equal to this one.
+    schema.flags = ARROW_FLAG_NULLABLE;
+    schema.n_children = static_cast<int64_t>(data->children.size());
+    schema.children = data->children.empty() ? nullptr : data->children.data();
+    schema.dictionary = nullptr;
+    schema.release = release_schema;
+    schema.private_data = data;
+}
+
+// `buffers` may point into `owned`: moving a vector keeps its heap block, so
+// pointers taken before the move stay valid after it.
+void set_array(ArrowArray& array, int64_t length, std::vector<uint8_t> owned,
+               std::vector<const void*> buffers, std::vector<ArrowArray*> children) {
+    auto* data = new ArrayData{std::move(owned), std::move(buffers), std::move(children)};
+
+    array.length = length;
+    // Nothing this node sends is null, so the validity bitmap - the first
+    // buffer of every node below - is left out entirely.
+    array.null_count = 0;
+    array.offset = 0;
+    array.n_buffers = static_cast<int64_t>(data->buffers.size());
+    array.n_children = static_cast<int64_t>(data->children.size());
+    array.buffers = data->buffers.data();
+    array.children = data->children.empty() ? nullptr : data->children.data();
+    array.dictionary = nullptr;
+    array.release = release_array;
+    array.private_data = data;
+}
+
+// One field of a struct, owned by its parent.
+struct Child {
+    ArrowSchema* schema;
+    ArrowArray* array;
+};
+
+Child new_child() {
+    return {new ArrowSchema{}, new ArrowArray{}};
+}
+
+void fill_uint32(ArrowSchema& schema, ArrowArray& array, const char* name, uint32_t value) {
+    std::vector<uint8_t> owned(sizeof(value));
+    std::memcpy(owned.data(), &value, sizeof(value));
+    const void* values = owned.data();
+
+    set_schema(schema, "I", name, {});
+    set_array(array, 1, std::move(owned), {nullptr, values}, {});
+}
+
+// One string, offsets and characters in a single allocation.
+void fill_utf8(ArrowSchema& schema, ArrowArray& array, const char* name, const char* text,
+               size_t size) {
+    const int32_t offsets[2] = {0, static_cast<int32_t>(size)};
+
+    std::vector<uint8_t> owned(sizeof(offsets) + size);
+    std::memcpy(owned.data(), offsets, sizeof(offsets));
+    std::memcpy(owned.data() + sizeof(offsets), text, size);
+    const void* offsets_buffer = owned.data();
+    const void* values_buffer = owned.data() + sizeof(offsets);
+
+    set_schema(schema, "u", name, {});
+    set_array(array, 1, std::move(owned), {nullptr, offsets_buffer, values_buffer}, {});
+}
+
+// One byte string. Only the offsets are owned; the bytes are the caller's.
+void fill_large_binary(ArrowSchema& schema, ArrowArray& array, const char* name,
+                       const uint8_t* data, size_t size) {
+    const int64_t offsets[2] = {0, static_cast<int64_t>(size)};
+
+    std::vector<uint8_t> owned(sizeof(offsets));
+    std::memcpy(owned.data(), offsets, sizeof(offsets));
+    const void* offsets_buffer = owned.data();
+
+    set_schema(schema, "Z", name, {});
+    set_array(array, 1, std::move(owned), {nullptr, offsets_buffer, data}, {});
+}
+
+} // namespace
+
+Exported image(uint32_t width, uint32_t height, const char* encoding, const uint8_t* data,
+               size_t size) {
+    Child w = new_child();
+    fill_uint32(*w.schema, *w.array, "width", width);
+
+    Child h = new_child();
+    fill_uint32(*h.schema, *h.array, "height", height);
+
+    Child e = new_child();
+    fill_utf8(*e.schema, *e.array, "encoding", encoding, std::strlen(encoding));
+
+    Child d = new_child();
+    fill_large_binary(*d.schema, *d.array, "data", data, size);
+
+    Exported out;
+    set_schema(out.schema, "+s", "", {w.schema, h.schema, e.schema, d.schema});
+    set_array(out.array, 1, {}, {nullptr}, {w.array, h.array, e.array, d.array});
+    return out;
+}
+
+Exported float32(const float* values, size_t count) {
+    Exported out;
+    set_schema(out.schema, "f", "", {});
+    set_array(out.array, static_cast<int64_t>(count), {}, {nullptr, values}, {});
+    return out;
+}
+
+Exported string(const char* text, size_t size) {
+    Exported out;
+    fill_utf8(out.schema, out.array, "", text, size);
+    return out;
+}
+
+} // namespace arrow_c
@@ -0,0 +1,75 @@
+#pragma once
+
+#include <cstddef>
+#include <cstdint>
+
+// The Arrow C data interface, verbatim from the Arrow specification.
+//
+// These two structs are the whole ABI dora's send_arrow_output takes, so
+// defining them here is what lets this node publish typed Arrow arrays without
+// linking Arrow C++ - a heavy dependency for a producer that exports one array
+// per output and never reads one.
+#ifndef ARROW_C_DATA_INTERFACE
+#define ARROW_C_DATA_INTERFACE
+
+#define ARROW_FLAG_DICTIONARY_ORDERED 1
+#define ARROW_FLAG_NULLABLE 2
+#define ARROW_FLAG_MAP_KEYS_SORTED 4
+
+struct ArrowSchema {
+    const char* format;
+    const char* name;
+    const char* metadata;
+    int64_t flags;
+    int64_t n_children;
+    struct ArrowSchema** children;
+    struct ArrowSchema* dictionary;
+
+    void (*release)(struct ArrowSchema*);
+    void* private_data;
+};
+
+struct ArrowArray {
+    int64_t length;
+    int64_t null_count;
+    int64_t offset;
+    int64_t n_buffers;
+    int64_t n_children;
+    const void** buffers;
+    struct ArrowArray** children;
+    struct ArrowArray* dictionary;
+
+    void (*release)(struct ArrowArray*);
+    void* private_data;
+};
+
+#endif // ARROW_C_DATA_INTERFACE
+
+namespace arrow_c {
+
+// One array with the schema describing it.
+//
+// dora moves both structs out of here and calls their release callbacks once it
+// has copied the payload into shared memory, so an Exported is built, sent
+// once, and never touched again.
+struct Exported {
+    ArrowArray array{};
+    ArrowSchema schema{};
+};
+
+// std/media/v1/Image: one row of {width, height, encoding, data}.
+//
+// The payload is borrowed rather than copied, so it has to stay valid until the
+// send returns. A capture-thread frame buffer does: the event loop holds the
+// frame across the call.
+Exported image(uint32_t width, uint32_t height, const char* encoding, const uint8_t* data,
+               size_t size);
+
+// std/core/v1/Float32: `count` values, borrowed on the same terms as image().
+Exported float32(const float* values, size_t count);
+
+// std/core/v1/String: one UTF-8 string. Copied, since every string this node
+// sends is a short state name.
+Exported string(const char* text, size_t size);
+
+} // namespace arrow_c
@@ -1,27 +0,0 @@
-#pragma once
-
-#include <sl/Camera.hpp>
-#include <string>
-#include <vector>
-
-namespace engines {
-
-struct DetectedObject {
-    int label_id;
-    float confidence;
-    float position[3];         // center x, y, z (mm)
-    float bounding_box_2d[8];  // 4 corners × 2 coords (pixels)
-    float bounding_box_3d[24]; // 8 corners × 3 coords (mm)
-};
-
-class Engine {
-public:
-    virtual ~Engine() = default;
-
-    virtual void enable(sl::Camera& camera) = 0;
-    virtual void detect(sl::Camera& camera) = 0;
-    virtual const std::vector<DetectedObject>& objects() const = 0;
-    virtual std::string label_names() const = 0;
-};
-
-} // namespace engines
@@ -1,136 +0,0 @@
-#pragma once
-
-#include <opencv2/opencv.hpp>
-#include <sl/Camera.hpp>
-
-#include <algorithm>
-#include <cmath>
-#include <vector>
-
-namespace engines::detail {
-
-// --- NMS ---
-
-struct RawDetection {
-    float x1, y1, x2, y2;
-    float score;
-    int class_id;
-};
-
-inline float iou(const RawDetection& a, const RawDetection& b) {
-    float inter_x1 = std::max(a.x1, b.x1);
-    float inter_y1 = std::max(a.y1, b.y1);
-    float inter_x2 = std::min(a.x2, b.x2);
-    float inter_y2 = std::min(a.y2, b.y2);
-    float inter_w = std::max(0.0f, inter_x2 - inter_x1);
-    float inter_h = std::max(0.0f, inter_y2 - inter_y1);
-    float inter_area = inter_w * inter_h;
-    float area_a = (a.x2 - a.x1) * (a.y2 - a.y1);
-    float area_b = (b.x2 - b.x1) * (b.y2 - b.y1);
-    float union_area = area_a + area_b - inter_area;
-    return union_area > 0.0f ? inter_area / union_area : 0.0f;
-}
-
-inline std::vector<RawDetection> nms(std::vector<RawDetection> dets, float threshold) {
-    std::sort(dets.begin(), dets.end(),
-              [](const RawDetection& a, const RawDetection& b) {
-                  return a.score > b.score;
-              });
-    std::vector<bool> suppressed(dets.size(), false);
-    std::vector<RawDetection> result;
-    for (size_t i = 0; i < dets.size(); i++) {
-        if (suppressed[i]) continue;
-        result.push_back(dets[i]);
-        for (size_t j = i + 1; j < dets.size(); j++) {
-            if (!suppressed[j] && iou(dets[i], dets[j]) > threshold)
-                suppressed[j] = true;
-        }
-    }
-    return result;
-}
-
-// --- Letterbox resize ---
-
-inline cv::Mat letterbox(const cv::Mat& src, int size,
-                         float& scale, float& pad_x, float& pad_y) {
-    float scale_w = static_cast<float>(size) / src.cols;
-    float scale_h = static_cast<float>(size) / src.rows;
-    scale = std::min(scale_w, scale_h);
-    int new_w = static_cast<int>(std::round(src.cols * scale));
-    int new_h = static_cast<int>(std::round(src.rows * scale));
-    pad_x = (size - new_w) / 2.0f;
-    pad_y = (size - new_h) / 2.0f;
-
-    cv::Mat resized;
-    cv::resize(src, resized, {new_w, new_h});
-
-    cv::Mat canvas(size, size, CV_8UC3, cv::Scalar(114, 114, 114));
-    resized.copyTo(canvas(cv::Rect(
-        static_cast<int>(pad_x), static_cast<int>(pad_y), new_w, new_h)));
-    return canvas;
-}
-
-// --- Point cloud fusion ---
-
-struct FusionResult {
-    float cx, cy, cz;
-    float depth_near, depth_far;
-    bool valid = false;
-};
-
-inline FusionResult fuse_bbox(const sl::Mat& pc, int x1, int y1, int x2, int y2) {
-    FusionResult result{};
-    int w = static_cast<int>(pc.getWidth());
-    int h = static_cast<int>(pc.getHeight());
-    x1 = std::max(x1, 0);
-    y1 = std::max(y1, 0);
-    x2 = std::min(x2, w - 1);
-    y2 = std::min(y2, h - 1);
-
-    std::vector<float> xs, ys, zs;
-    xs.reserve((x2 - x1) * (y2 - y1));
-    ys.reserve(xs.capacity());
-    zs.reserve(xs.capacity());
-
-    for (int y = y1; y <= y2; y++) {
-        for (int x = x1; x <= x2; x++) {
-            sl::float4 pt;
-            pc.getValue(x, y, &pt);
-            if (!std::isnan(pt.x) && !std::isnan(pt.y) && !std::isnan(pt.z) &&
-                !std::isinf(pt.x) && !std::isinf(pt.y) && !std::isinf(pt.z)) {
-                xs.push_back(pt.x);
-                ys.push_back(pt.y);
-                zs.push_back(pt.z);
-            }
-        }
-    }
-
-    if (xs.empty()) return result;
-
-    std::sort(xs.begin(), xs.end());
-    std::sort(ys.begin(), ys.end());
-    std::sort(zs.begin(), zs.end());
-
-    size_t n   = xs.size();
-    size_t mid = n / 2;
-    size_t p25 = n / 4;
-    size_t p75 = 3 * n / 4;
-
-    result.cx         = xs[mid];
-    result.cy         = ys[mid];
-    result.cz         = zs[mid];
-    result.depth_near = zs[p25];
-    result.depth_far  = zs[p75];
-    result.valid      = true;
-    return result;
-}
-
-inline void backproject(float u, float v, float z,
-                        float fx, float fy, float cx, float cy,
-                        float& X, float& Y, float& Z) {
-    Z = z;
-    X = (u - cx) * z / fx;
-    Y = (v - cy) * z / fy;
-}
-
-} // namespace engines::detail
@@ -1,369 +0,0 @@
-#include "engines/yolo_onnx.h"
-#include "engines/yolo_helpers.h"
-#include "util/env.h"
-
-#include <onnxruntime_cxx_api.h>
-#include <opencv2/opencv.hpp>
-#include <sl/Camera.hpp>
-
-#include <cmath>
-#include <fstream>
-#include <iostream>
-#include <string>
-#include <vector>
-
-namespace engines {
-
-using namespace detail;
-
-// --- Impl ---
-
-struct YoloOnnx::Impl {
-    Ort::Env env{ORT_LOGGING_LEVEL_WARNING, "yolo_onnx"};
-    Ort::SessionOptions session_options;
-    std::unique_ptr<Ort::Session> session;
-    Ort::AllocatorWithDefaultOptions allocator;
-
-    std::string input_name;
-    std::string output_name;
-    int num_classes = 0;
-    YoloOutputLayout resolved_layout = YoloOutputLayout::NC_FIRST;
-
-    std::vector<RawDetection> run_inference(const YoloOnnxConfig& config,
-                                            const cv::Mat& image_bgr);
-};
-
-// --- Impl::run_inference ---
-
-std::vector<RawDetection> YoloOnnx::Impl::run_inference(
-    const YoloOnnxConfig& config, const cv::Mat& image_bgr)
-{
-    if (!session) return {};
-
-    int orig_w = image_bgr.cols;
-    int orig_h = image_bgr.rows;
-
-    cv::Mat rgb;
-    cv::cvtColor(image_bgr, rgb, cv::COLOR_BGR2RGB);
-
-    float scale, pad_x, pad_y;
-    cv::Mat lb = letterbox(rgb, config.input_size, scale, pad_x, pad_y);
-
-    cv::Mat lb_float;
-    lb.convertTo(lb_float, CV_32F, 1.0f / 255.0f);
-
-    int sz = config.input_size;
-    std::vector<float> input_data(3 * sz * sz);
-    for (int c = 0; c < 3; c++) {
-        for (int h = 0; h < sz; h++) {
-            for (int w = 0; w < sz; w++) {
-                input_data[c * sz * sz + h * sz + w] =
-                    lb_float.at<cv::Vec3f>(h, w)[c];
-            }
-        }
-    }
-
-    auto mem_info = Ort::MemoryInfo::CreateCpu(
-        OrtAllocatorType::OrtArenaAllocator, OrtMemTypeDefault);
-
-    std::vector<int64_t> image_shape{1, 3, sz, sz};
-    Ort::Value image_tensor = Ort::Value::CreateTensor<float>(
-        mem_info, input_data.data(), input_data.size(),
-        image_shape.data(), image_shape.size());
-
-    const char* input_name_cstr  = input_name.c_str();
-    const char* output_name_cstr = output_name.c_str();
-
-    std::vector<Ort::Value> outputs;
-    try {
-        outputs = session->Run(
-            Ort::RunOptions{nullptr},
-            &input_name_cstr, &image_tensor, 1,
-            &output_name_cstr, 1);
-    } catch (const Ort::Exception& e) {
-        std::cerr << "YoloOnnx: inference failed: " << e.what() << std::endl;
-        return {};
-    }
-
-    auto out_shape = outputs[0].GetTensorTypeAndShapeInfo().GetShape();
-    if (out_shape.size() < 3) return {};
-
-    const float* out = outputs[0].GetTensorData<float>();
-    int nc = num_classes;
-    if (nc <= 0) return {};
-
-    std::vector<RawDetection> candidates;
-
-    if (resolved_layout == YoloOutputLayout::NC_FIRST) {
-        // (1, 4+N, anchors) — YOLOv8, YOLOv11
-        int num_anchors = static_cast<int>(out_shape[2]);
-        for (int a = 0; a < num_anchors; a++) {
-            float cx_lb = out[0 * num_anchors + a];
-            float cy_lb = out[1 * num_anchors + a];
-            float w_lb  = out[2 * num_anchors + a];
-            float h_lb  = out[3 * num_anchors + a];
-
-            float best_score = 0.0f;
-            int   best_class = 0;
-            for (int c = 0; c < nc; c++) {
-                float s = out[(4 + c) * num_anchors + a];
-                if (s > best_score) { best_score = s; best_class = c; }
-            }
-            if (best_score < config.confidence_threshold) continue;
-
-            float x1_lb = cx_lb - w_lb / 2.0f;
-            float y1_lb = cy_lb - h_lb / 2.0f;
-            float x2_lb = cx_lb + w_lb / 2.0f;
-            float y2_lb = cy_lb + h_lb / 2.0f;
-
-            float x1 = std::max(0.0f, std::min((x1_lb - pad_x) / scale, static_cast<float>(orig_w - 1)));
-            float y1 = std::max(0.0f, std::min((y1_lb - pad_y) / scale, static_cast<float>(orig_h - 1)));
-            float x2 = std::max(0.0f, std::min((x2_lb - pad_x) / scale, static_cast<float>(orig_w - 1)));
-            float y2 = std::max(0.0f, std::min((y2_lb - pad_y) / scale, static_cast<float>(orig_h - 1)));
-            candidates.push_back({x1, y1, x2, y2, best_score, best_class});
-        }
-    } else {
-        // (1, anchors, 4+N) or (1, anchors, 5+N)
-        int num_anchors = static_cast<int>(out_shape[1]);
-        int row_stride  = static_cast<int>(out_shape[2]);
-        int cls_offset  = (resolved_layout == YoloOutputLayout::NC_LAST_OBJ) ? 5 : 4;
-
-        for (int a = 0; a < num_anchors; a++) {
-            const float* row = out + a * row_stride;
-            float cx_lb = row[0], cy_lb = row[1], w_lb = row[2], h_lb = row[3];
-            float obj_conf = (resolved_layout == YoloOutputLayout::NC_LAST_OBJ) ? row[4] : 1.0f;
-
-            float best_score = 0.0f;
-            int   best_class = 0;
-            for (int c = 0; c < nc; c++) {
-                float s = obj_conf * row[cls_offset + c];
-                if (s > best_score) { best_score = s; best_class = c; }
-            }
-            if (best_score < config.confidence_threshold) continue;
-
-            float x1_lb = cx_lb - w_lb / 2.0f;
-            float y1_lb = cy_lb - h_lb / 2.0f;
-            float x2_lb = cx_lb + w_lb / 2.0f;
-            float y2_lb = cy_lb + h_lb / 2.0f;
-
-            float x1 = std::max(0.0f, std::min((x1_lb - pad_x) / scale, static_cast<float>(orig_w - 1)));
-            float y1 = std::max(0.0f, std::min((y1_lb - pad_y) / scale, static_cast<float>(orig_h - 1)));
-            float x2 = std::max(0.0f, std::min((x2_lb - pad_x) / scale, static_cast<float>(orig_w - 1)));
-            float y2 = std::max(0.0f, std::min((y2_lb - pad_y) / scale, static_cast<float>(orig_h - 1)));
-            candidates.push_back({x1, y1, x2, y2, best_score, best_class});
-        }
-    }
-
-    return nms(std::move(candidates), config.nms_threshold);
-}
-
-// --- Config ---
-
-YoloOnnxConfig YoloOnnxConfig::from_env() {
-    YoloOnnxConfig c;
-    c.model_path           = util::get_env_str("ZED_ONNX_MODEL_PATH",      c.model_path);
-    c.confidence_threshold = util::get_env_float("ZED_ONNX_CONFIDENCE",    c.confidence_threshold);
-    c.nms_threshold        = util::get_env_float("ZED_ONNX_NMS_THRESHOLD", c.nms_threshold);
-    c.input_size           = util::get_env_int("ZED_ONNX_INPUT_SIZE",      c.input_size);
-    c.labels               = util::get_env_str("ZED_ONNX_LABELS",          c.labels);
-    c.labels_file          = util::get_env_str("ZED_ONNX_LABELS_FILE",     c.labels_file);
-
-    std::string fmt = util::get_env_str("ZED_ONNX_OUTPUT_FORMAT", "");
-    if      (fmt == "nc_first"    || fmt == "yolov8" || fmt == "yolov11")
-        c.output_layout = YoloOutputLayout::NC_FIRST;
-    else if (fmt == "nc_last")
-        c.output_layout = YoloOutputLayout::NC_LAST;
-    else if (fmt == "nc_last_obj" || fmt == "yolov5")
-        c.output_layout = YoloOutputLayout::NC_LAST_OBJ;
-
-    return c;
-}
-
-// --- YoloOnnx ---
-
-YoloOnnx::YoloOnnx(const YoloOnnxConfig& config)
-    : config_(config), impl_(std::make_unique<Impl>()) {}
-
-YoloOnnx::~YoloOnnx() = default;
-
-void YoloOnnx::enable(sl::Camera& /* camera */) {
-    if (config_.model_path.empty()) {
-        std::cerr << "YoloOnnx: ZED_ONNX_MODEL_PATH is not set." << std::endl;
-        return;
-    }
-
-    OrtCUDAProviderOptions cuda_opts{};
-    cuda_opts.device_id = 0;
-    try {
-        impl_->session_options.AppendExecutionProvider_CUDA(cuda_opts);
-    } catch (const Ort::Exception& e) {
-        std::cerr << "YoloOnnx: CUDA unavailable (" << e.what() << "), using CPU." << std::endl;
-    }
-    impl_->session_options.SetGraphOptimizationLevel(GraphOptimizationLevel::ORT_ENABLE_ALL);
-
-    std::cout << "YoloOnnx: loading model (" << config_.model_path << ")..." << std::endl;
-    try {
-        impl_->session = std::make_unique<Ort::Session>(
-            impl_->env, config_.model_path.c_str(), impl_->session_options);
-    } catch (const Ort::Exception& e) {
-        std::cerr << "YoloOnnx: failed to load model: " << e.what() << std::endl;
-        return;
-    }
-
-    impl_->input_name  = impl_->session->GetInputNameAllocated(0, impl_->allocator).get();
-    impl_->output_name = impl_->session->GetOutputNameAllocated(0, impl_->allocator).get();
-
-    size_t num_inputs = impl_->session->GetInputCount();
-    if (num_inputs >= 2) {
-        std::cerr << "YoloOnnx: model has " << num_inputs << " inputs — "
-                     "this engine only supports single-input models."
-                  << std::endl;
-    }
-
-    auto out_info = impl_->session->GetOutputTypeInfo(0).GetTensorTypeAndShapeInfo();
-    auto shape    = out_info.GetShape();
-    if (shape.size() == 3) {
-        int64_t dim1 = shape[1];
-        int64_t dim2 = shape[2];
-
-        YoloOutputLayout resolved;
-        if (config_.output_layout == YoloOutputLayout::AUTO) {
-            // dim1 < dim2 → NC_FIRST (e.g. 84 vs 8400 for YOLOv8/11)
-            // dim1 > dim2 → NC_LAST_OBJ (e.g. 25200 vs 85 for YOLOv5)
-            resolved = (dim1 < dim2) ? YoloOutputLayout::NC_FIRST
-                                     : YoloOutputLayout::NC_LAST_OBJ;
-        } else {
-            resolved = config_.output_layout;
-        }
-        impl_->resolved_layout = resolved;
-
-        if (resolved == YoloOutputLayout::NC_FIRST) {
-            impl_->num_classes = static_cast<int>(dim1) - 4;
-        } else if (resolved == YoloOutputLayout::NC_LAST) {
-            impl_->num_classes = static_cast<int>(dim2) - 4;
-        } else { // NC_LAST_OBJ
-            impl_->num_classes = static_cast<int>(dim2) - 5;
-        }
-    }
-
-    if (!config_.labels_file.empty() && config_.labels.empty()) {
-        std::ifstream lf(config_.labels_file);
-        if (!lf) {
-            std::cerr << "YoloOnnx: cannot open ZED_ONNX_LABELS_FILE: "
-                      << config_.labels_file << std::endl;
-        } else {
-            std::string line, joined;
-            while (std::getline(lf, line)) {
-                size_t l = line.find_first_not_of(" \t\r");
-                size_t r = line.find_last_not_of(" \t\r");
-                if (l == std::string::npos) continue;
-                if (!joined.empty()) joined += ',';
-                joined += line.substr(l, r - l + 1);
-            }
-            if (!joined.empty()) {
-                config_.labels = joined;
-                std::cout << "YoloOnnx: loaded labels from file ("
-                          << config_.labels_file << ")" << std::endl;
-            }
-        }
-    }
-
-    std::cout << "YoloOnnx: model loaded."
-              << " Classes=" << impl_->num_classes
-              << " Layout=" << (impl_->resolved_layout == YoloOutputLayout::NC_FIRST ? "NC_FIRST"
-                              : impl_->resolved_layout == YoloOutputLayout::NC_LAST  ? "NC_LAST"
-                                                                                      : "NC_LAST_OBJ")
-              << std::endl;
-}
-
-void YoloOnnx::detect(sl::Camera& camera) {
-    detected_.clear();
-    if (!impl_->session) return;
-
-    sl::Mat img_mat;
-    camera.retrieveImage(img_mat, sl::VIEW::LEFT);
-
-    sl::Mat pc_mat;
-    camera.retrieveMeasure(pc_mat, sl::MEASURE::XYZRGBA);
-
-    sl::CameraInformation info = camera.getCameraInformation();
-    auto calib = info.camera_configuration.calibration_parameters.left_cam;
-    float fx = calib.fx, fy = calib.fy, cx = calib.cx, cy = calib.cy;
-
-    int orig_w = static_cast<int>(img_mat.getWidth());
-    int orig_h = static_cast<int>(img_mat.getHeight());
-
-    cv::Mat rgba(orig_h, orig_w, CV_8UC4, img_mat.getPtr<sl::uchar1>());
-    cv::Mat bgr;
-    cv::cvtColor(rgba, bgr, cv::COLOR_RGBA2BGR);
-
-    auto kept = impl_->run_inference(config_, bgr);
-
-    for (const auto& det : kept) {
-        FusionResult fusion = fuse_bbox(pc_mat,
-            static_cast<int>(det.x1), static_cast<int>(det.y1),
-            static_cast<int>(det.x2), static_cast<int>(det.y2));
-
-        DetectedObject obj{};
-        obj.label_id   = det.class_id;
-        obj.confidence = det.score * 100.0f;
-
-        if (fusion.valid) {
-            obj.position[0] = fusion.cx;
-            obj.position[1] = fusion.cy;
-            obj.position[2] = fusion.cz;
-        }
-
-        obj.bounding_box_2d[0] = det.x1; obj.bounding_box_2d[1] = det.y1;
-        obj.bounding_box_2d[2] = det.x2; obj.bounding_box_2d[3] = det.y1;
-        obj.bounding_box_2d[4] = det.x2; obj.bounding_box_2d[5] = det.y2;
-        obj.bounding_box_2d[6] = det.x1; obj.bounding_box_2d[7] = det.y2;
-
-        if (fusion.valid) {
-            float corners_u[4] = {det.x1, det.x2, det.x2, det.x1};
-            float corners_v[4] = {det.y1, det.y1, det.y2, det.y2};
-            float depths[2]    = {fusion.depth_near, fusion.depth_far};
-            for (int face = 0; face < 2; face++) {
-                for (int c = 0; c < 4; c++) {
-                    float X, Y, Z;
-                    backproject(corners_u[c], corners_v[c], depths[face],
-                                fx, fy, cx, cy, X, Y, Z);
-                    int idx = (face * 4 + c) * 3;
-                    obj.bounding_box_3d[idx + 0] = X;
-                    obj.bounding_box_3d[idx + 1] = Y;
-                    obj.bounding_box_3d[idx + 2] = Z;
-                }
-            }
-        }
-
-        detected_.push_back(obj);
-    }
-}
-
-void YoloOnnx::detect(const cv::Mat& image_bgr) {
-    detected_.clear();
-    if (!impl_->session) return;
-
-    auto kept = impl_->run_inference(config_, image_bgr);
-
-    for (const auto& det : kept) {
-        DetectedObject obj{};
-        obj.label_id   = det.class_id;
-        obj.confidence = det.score * 100.0f;
-        obj.bounding_box_2d[0] = det.x1; obj.bounding_box_2d[1] = det.y1;
-        obj.bounding_box_2d[2] = det.x2; obj.bounding_box_2d[3] = det.y1;
-        obj.bounding_box_2d[4] = det.x2; obj.bounding_box_2d[5] = det.y2;
-        obj.bounding_box_2d[6] = det.x1; obj.bounding_box_2d[7] = det.y2;
-        detected_.push_back(obj);
-    }
-}
-
-const std::vector<DetectedObject>& YoloOnnx::objects() const {
-    return detected_;
-}
-
-std::string YoloOnnx::label_names() const {
-    return config_.labels;
-}
-
-} // namespace engines
@@ -1,48 +0,0 @@
-#pragma once
-
-#include "engines/engine.h"
-
-#include <opencv2/core.hpp>
-#include <memory>
-#include <string>
-
-namespace engines {
-
-enum class YoloOutputLayout {
-    AUTO,          // detect from output tensor shape at load time
-    NC_FIRST,      // (1, 4+N, anchors) — YOLOv8, YOLOv11
-    NC_LAST,       // (1, anchors, 4+N) — rows-first, no objectness
-    NC_LAST_OBJ    // (1, anchors, 5+N) — YOLOv5, rows-first with objectness
-};
-
-struct YoloOnnxConfig {
-    std::string model_path;              // ZED_ONNX_MODEL_PATH (required)
-    float confidence_threshold = 0.25f;  // ZED_ONNX_CONFIDENCE
-    float nms_threshold = 0.45f;         // ZED_ONNX_NMS_THRESHOLD
-    int input_size = 640;                // ZED_ONNX_INPUT_SIZE
-    std::string labels;                  // ZED_ONNX_LABELS (comma-separated)
-    std::string labels_file;             // ZED_ONNX_LABELS_FILE (one class name per line)
-    YoloOutputLayout output_layout = YoloOutputLayout::AUTO;
-
-    static YoloOnnxConfig from_env();
-};
-
-class YoloOnnx : public Engine {
-public:
-    explicit YoloOnnx(const YoloOnnxConfig& config);
-    ~YoloOnnx() override;
-
-    void enable(sl::Camera& camera) override;
-    void detect(sl::Camera& camera) override;
-    void detect(const cv::Mat& image_bgr);      // image-only; no 3D fusion
-    const std::vector<DetectedObject>& objects() const override;
-    std::string label_names() const override;
-
-private:
-    YoloOnnxConfig config_;
-    struct Impl;
-    std::unique_ptr<Impl> impl_;
-    std::vector<DetectedObject> detected_;
-};
-
-} // namespace engines
@@ -1,99 +0,0 @@
-#include "engines/zed_native.h"
-#include "util/env.h"
-
-#include <iostream>
-#include <string>
-
-namespace {
-
-sl::OBJECT_DETECTION_MODEL parse_detection_model(const std::string& model) {
-    if (model == "MULTI_CLASS_BOX_FAST") {
-        return sl::OBJECT_DETECTION_MODEL::MULTI_CLASS_BOX_FAST;
-    }
-    if (model == "MULTI_CLASS_BOX_ACCURATE") {
-        return sl::OBJECT_DETECTION_MODEL::MULTI_CLASS_BOX_ACCURATE;
-    }
-    return sl::OBJECT_DETECTION_MODEL::MULTI_CLASS_BOX_MEDIUM;
-}
-
-} // namespace
-
-namespace engines {
-
-DetectionConfig DetectionConfig::from_env() {
-    DetectionConfig c;
-    c.model = util::get_env_str("ZED_DETECTION_MODEL", c.model);
-    c.confidence_threshold = util::get_env_float("ZED_DETECTION_CONFIDENCE", c.confidence_threshold);
-    c.tracking = util::get_env_bool("ZED_DETECTION_TRACKING", c.tracking);
-    return c;
-}
-
-ZedNative::ZedNative(const DetectionConfig& config) : config_(config) {
-    det_params_.detection_model = parse_detection_model(config_.model);
-    det_params_.enable_tracking = config_.tracking;
-    det_params_.enable_segmentation = false;
-
-    det_rt_params_.detection_confidence_threshold = config_.confidence_threshold;
-}
-
-void ZedNative::enable(sl::Camera& camera) {
-    if (config_.tracking) {
-        sl::PositionalTrackingParameters tracking_params;
-        sl::ERROR_CODE err = camera.enablePositionalTracking(tracking_params);
-        if (err != sl::ERROR_CODE::SUCCESS) {
-            std::cerr << "Failed to enable positional tracking: "
-                      << sl::toString(err) << std::endl;
-        }
-    }
-
-    std::cout << "Object Detection: loading model (" << config_.model << ")..." << std::endl;
-    sl::ERROR_CODE err = camera.enableObjectDetection(det_params_);
-    if (err != sl::ERROR_CODE::SUCCESS) {
-        std::cerr << "Failed to enable object detection: "
-                  << sl::toString(err) << std::endl;
-        return;
-    }
-    std::cout << "Object Detection: model loaded." << std::endl;
-}
-
-void ZedNative::detect(sl::Camera& camera) {
-    detected_.clear();
-
-    sl::ERROR_CODE err = camera.retrieveObjects(raw_objects_, det_rt_params_);
-    if (err != sl::ERROR_CODE::SUCCESS) {
-        return;
-    }
-
-    for (const auto& obj : raw_objects_.object_list) {
-        DetectedObject det{};
-        det.label_id = static_cast<int>(obj.label);
-        det.confidence = obj.confidence;
-
-        det.position[0] = obj.position.x;
-        det.position[1] = obj.position.y;
-        det.position[2] = obj.position.z;
-
-        for (int i = 0; i < 4 && i < static_cast<int>(obj.bounding_box_2d.size()); i++) {
-            det.bounding_box_2d[i * 2 + 0] = obj.bounding_box_2d[i].x;
-            det.bounding_box_2d[i * 2 + 1] = obj.bounding_box_2d[i].y;
-        }
-
-        for (int i = 0; i < 8 && i < static_cast<int>(obj.bounding_box.size()); i++) {
-            det.bounding_box_3d[i * 3 + 0] = obj.bounding_box[i].x;
-            det.bounding_box_3d[i * 3 + 1] = obj.bounding_box[i].y;
-            det.bounding_box_3d[i * 3 + 2] = obj.bounding_box[i].z;
-        }
-
-        detected_.push_back(det);
-    }
-}
-
-const std::vector<DetectedObject>& ZedNative::objects() const {
-    return detected_;
-}
-
-std::string ZedNative::label_names() const {
-    return "PERSON,VEHICLE,BAG,ANIMAL,ELECTRONICS,FRUIT_VEGETABLE,SPORT";
-}
-
-} // namespace engines
@@ -1,34 +0,0 @@
-#pragma once
-
-#include "engines/engine.h"
-
-#include <string>
-
-namespace engines {
-
-struct DetectionConfig {
-    std::string model = "MULTI_CLASS_BOX_MEDIUM";
-    float confidence_threshold = 40.0f;
-    bool tracking = false;
-
-    static DetectionConfig from_env();
-};
-
-class ZedNative : public Engine {
-public:
-    explicit ZedNative(const DetectionConfig& config);
-
-    void enable(sl::Camera& camera) override;
-    void detect(sl::Camera& camera) override;
-    const std::vector<DetectedObject>& objects() const override;
-    std::string label_names() const override;
-
-private:
-    DetectionConfig config_;
-    sl::ObjectDetectionParameters det_params_;
-    sl::ObjectDetectionRuntimeParameters det_rt_params_;
-    sl::Objects raw_objects_;
-    std::vector<DetectedObject> detected_;
-};
-
-} // namespace engines
@@ -1,32 +1,25 @@
-#include "engines/engine.h"
-#include "engines/yolo_onnx.h"
-#include "engines/zed_native.h"
-#include "util/env.h"
-#include "zed/camera.h"
+#include "arrow/array.h"
+#include "zed/capture.h"

 #include <dora-node-api.h>
-#include <opencv2/opencv.hpp>

 #include <chrono>
-#include <cstring>
+#include <cstdint>
+#include <cstdlib>
 #include <initializer_list>
 #include <iostream>
-#include <memory>
 #include <string>
+#include <utility>
 #include <vector>

 namespace {

-constexpr int FIELDS_PER_OBJECT = 37;
-
-enum class PcMode { FULL, HALF, ROI };
-
-rust::Vec<int64_t> make_shape(int height, int width, int channels) {
-    rust::Vec<int64_t> shape;
-    shape.push_back(height);
-    shape.push_back(width);
-    shape.push_back(channels);
-    return shape;
+rust::Vec<int64_t> make_vector_int(std::initializer_list<int64_t> values) {
+    rust::Vec<int64_t> out;
+    for (int64_t v : values) {
+        out.push_back(v);
+    }
+    return out;
 }

 rust::Vec<double> make_distortion(const std::vector<double>& distortion) {
@@ -37,58 +30,64 @@ rust::Vec<double> make_distortion(const std::vector<double>& distortion) {
    return values;
 }

-rust::Vec<int64_t> make_vector_int(std::initializer_list<int64_t> values) {
-    rust::Vec<int64_t> out;
-    for (int64_t v : values) {
-        out.push_back(v);
-    }
-    return out;
+void set_intrinsics(Metadata& metadata, const zed::Calibration& calib) {
+    metadata.set_float("fx", calib.fx);
+    metadata.set_float("fy", calib.fy);
+    metadata.set_float("cx", calib.cx);
+    metadata.set_float("cy", calib.cy);
+    metadata.set_list_float("distortion", make_distortion(calib.distortion));
 }

-std::vector<float> serialize_objects(const std::vector<engines::DetectedObject>& objects) {
-    std::vector<float> buffer(objects.size() * FIELDS_PER_OBJECT);
-    for (size_t i = 0; i < objects.size(); i++) {
-        float* row = buffer.data() + i * FIELDS_PER_OBJECT;
-        const auto& obj = objects[i];
-        row[0] = static_cast<float>(obj.label_id);
-        row[1] = obj.confidence;
-        row[2] = obj.position[0];
-        row[3] = obj.position[1];
-        row[4] = obj.position[2];
-        std::memcpy(row + 5, obj.bounding_box_2d, sizeof(obj.bounding_box_2d));
-        std::memcpy(row + 13, obj.bounding_box_3d, sizeof(obj.bounding_box_3d));
+// Both clocks are needed. The device timestamp is the instant the frame was
+// captured and is the only value two nodes reading the same frame can agree on.
+// The host timestamp is what the rest of the dataflow and the session recorder
+// share, and on a Jetson it can step when NTP synchronises after boot - which is
+// exactly why the device timestamp is recorded alongside it rather than instead
+// of it.
+void set_frame_stamps(Metadata& metadata, const zed::Frame& frame) {
+    metadata.set_int("frame_id", frame.frame_id);
+    metadata.set_timestamp("device_timestamp_ns", frame.device_ns);
+    metadata.set_timestamp("host_timestamp_ns", frame.host_ns);
+}
+
+// Publish one Arrow array. dora moves both structs out and releases them once
+// the payload is in shared memory, so the buffers they borrow only have to
+// outlive this call - which the frame the caller is holding does.
+void send(DoraNode& dora_node, const char* id, arrow_c::Exported payload,
+          rust::Box<Metadata> metadata) {
+    auto result = send_arrow_output(dora_node.send_output, id,
+                                    reinterpret_cast<uint8_t*>(&payload.array),
+                                    reinterpret_cast<uint8_t*>(&payload.schema),
+                                    std::move(metadata));
+
+    if (!std::string(result.error).empty()) {
+        std::cerr << "Error sending " << id << ": " << std::string(result.error) << std::endl;
    }
-    return buffer;
+}
+
+int64_t host_timestamp_ns() {
+    return std::chrono::duration_cast<std::chrono::nanoseconds>(
+               std::chrono::system_clock::now().time_since_epoch())
+        .count();
 }

 } // namespace

 int main() {
+    // Read the environment before joining the dataflow, so a bad configuration
+    // fails with its own message rather than after the node has registered.
+    auto config = zed::Config::from_env();
+
    auto dora_node = init_dora_node();

-    auto config = zed::Config::from_env();
-    zed::Camera camera(config);
-    camera.open();
-    camera.warmup();
-    auto calib = camera.calibration();
+    // The camera runs on its own thread. The SDK can block for an unbounded time
+    // inside grab() and open() when the camera is disconnected, so nothing below
+    // may call into it: this loop only reads what the capture thread has already
+    // produced, which is what keeps Stop answerable while the camera is down.
+    zed::Capture capture(config);
+    capture.start();

-    std::string engine_name = util::get_env_str("ZED_ENGINE", "native");
-    std::unique_ptr<engines::Engine> detector;
-    if (engine_name == "yolo_onnx" || engine_name == "onnx") {
-        auto cfg = engines::YoloOnnxConfig::from_env();
-        detector = std::make_unique<engines::YoloOnnx>(cfg);
-    } else {
-        auto cfg = engines::DetectionConfig::from_env();
-        detector = std::make_unique<engines::ZedNative>(cfg);
-    }
-    detector->enable(camera.handle());
-
-    std::string pc_mode_str = util::get_env_str("ZED_PC_MODE", "FULL");
-    PcMode pc_mode = (pc_mode_str == "HALF") ? PcMode::HALF
-                   : (pc_mode_str == "ROI")  ? PcMode::ROI
-                                             : PcMode::FULL;
-
-    int64_t frame_id = 0;
+    zed::Frame frame;
    while (true) {
        auto event = dora_node.events->next();
        auto type = event_type(event);
@@ -101,180 +100,91 @@ int main() {
            continue;
        }

-        if (!camera.grab()) {
-            std::cerr << "Grab failed; attempting to reconnect..." << std::endl;
-            camera.close();
-            camera.open();
-            calib = camera.calibration();
-            detector->enable(camera.handle());
+        std::string state;
+        if (capture.take_state_change(state)) {
+            auto state_metadata = new_metadata();
+            state_metadata->set_timestamp("host_timestamp_ns", host_timestamp_ns());
+
+            send(dora_node, "camera_state", arrow_c::string(state.data(), state.size()),
+                 std::move(state_metadata));
+        }
+
+        // No new frame since the last tick: the camera is slower than the timer,
+        // or it is down and the capture thread is recovering it.
+        if (!capture.take_frame(frame)) {
            continue;
        }

-        detector->detect(camera.handle());
-
-        sl::Mat& image_mat = camera.image();
-        sl::Mat& point_cloud_mat = camera.point_cloud();
-
-        int width = image_mat.getWidth();
-        int height = image_mat.getHeight();
-
-        int64_t current_frame_id = frame_id++;
-        int64_t timestamp_ns = static_cast<int64_t>(
-            std::chrono::duration_cast<std::chrono::nanoseconds>(
-                std::chrono::steady_clock::now().time_since_epoch()
-            ).count()
-        );
-
-        // --- image_bgr ---
-        cv::Mat image_rgba(height, width, CV_8UC4, image_mat.getPtr<sl::uchar1>());
-        cv::Mat image_bgr;
-        cv::cvtColor(image_rgba, image_bgr, cv::COLOR_BGRA2BGR);
-
-        const auto image_size = static_cast<size_t>(image_bgr.total() * image_bgr.elemSize());
-        rust::Slice<const uint8_t> image_slice{
-            reinterpret_cast<const uint8_t*>(image_bgr.data), image_size};
+        auto width = static_cast<uint32_t>(frame.width);
+        auto height = static_cast<uint32_t>(frame.height);

+        // --- image ---
+        // The payload carries its own width, height and encoding, so none of
+        // that travels as metadata: what is left is what describes the frame
+        // rather than the picture.
        auto image_metadata = new_metadata();
-        image_metadata->set_string("dtype", "uint8");
-        image_metadata->set_string("encoding", "bgr8");
-        image_metadata->set_string("layout", "HWC");
-        image_metadata->set_list_int("shape", make_shape(height, width, 3));
-        image_metadata->set_float("fx", calib.fx);
-        image_metadata->set_float("fy", calib.fy);
-        image_metadata->set_float("cx", calib.cx);
-        image_metadata->set_float("cy", calib.cy);
-        image_metadata->set_list_float("distortion", make_distortion(calib.distortion));
-        image_metadata->set_int("frame_id", current_frame_id);
-        image_metadata->set_int("timestamp_ns", timestamp_ns);
+        set_intrinsics(*image_metadata, frame.calib);
+        set_frame_stamps(*image_metadata, frame);

-        auto image_result = send_output_with_metadata(
-            dora_node.send_output, "image_bgr", image_slice, std::move(image_metadata));
-        if (!std::string(image_result.error).empty()) {
-            std::cerr << "Error sending image_bgr: " << std::string(image_result.error) << std::endl;
-        }
+        send(dora_node, "image",
+             arrow_c::image(width, height, "bgr8", frame.image_bgr.data(), frame.image_bgr.size()),
+             std::move(image_metadata));
+
+        // --- depth ---
+        // A depth map is an image whose pixels are distances, which is how ROS
+        // spells it too: 32FC1 is one float32 per pixel, and `units` says what
+        // those floats measure.
+        auto depth_metadata = new_metadata();
+        depth_metadata->set_string("units", "mm");
+        set_intrinsics(*depth_metadata, frame.calib);
+        set_frame_stamps(*depth_metadata, frame);
+
+        send(dora_node, "depth",
+             arrow_c::image(width, height, "32FC1",
+                            reinterpret_cast<const uint8_t*>(frame.depth.data()),
+                            frame.depth.size() * sizeof(float)),
+             std::move(depth_metadata));

        // --- point_cloud ---
-        int pc_width  = point_cloud_mat.getWidth();
-        int pc_height = point_cloud_mat.getHeight();
-
-        std::vector<float> pc_buf;
-        const uint8_t* pc_data_ptr = nullptr;
-        size_t         pc_data_size = 0;
-        auto pc_metadata = new_metadata();
-        pc_metadata->set_string("dtype", "float32");
-        pc_metadata->set_string("channels", "XYZRGBA");
-        pc_metadata->set_string("units", "mm");
-        pc_metadata->set_float("fx", calib.fx);
-        pc_metadata->set_float("fy", calib.fy);
-        pc_metadata->set_float("cx", calib.cx);
-        pc_metadata->set_float("cy", calib.cy);
-        pc_metadata->set_list_float("distortion", make_distortion(calib.distortion));
-
-        if (pc_mode == PcMode::HALF) {
-            int hw = pc_width / 2, hh = pc_height / 2;
-            pc_buf.resize(static_cast<size_t>(hh * hw * 4));
-            const sl::float4* src = point_cloud_mat.getPtr<sl::float4>();
-            for (int y = 0; y < hh; y++) {
-                for (int x = 0; x < hw; x++) {
-                    const sl::float4& pt = src[(y * 2) * pc_width + (x * 2)];
-                    float* dst = pc_buf.data() + (y * hw + x) * 4;
-                    dst[0] = pt.x; dst[1] = pt.y; dst[2] = pt.z; dst[3] = pt.w;
-                }
-            }
+        if (frame.has_point_cloud) {
+            // Unlike the two images, a cloud is a flat array of values: its
+            // grid shape is only in the metadata.
+            auto pc_metadata = new_metadata();
+            pc_metadata->set_string("channels", "XYZRGBA");
+            pc_metadata->set_string("units", "mm");
            pc_metadata->set_string("layout", "HWC");
-            pc_metadata->set_list_int("shape", make_shape(hh, hw, 4));
-            pc_data_ptr  = reinterpret_cast<const uint8_t*>(pc_buf.data());
-            pc_data_size = pc_buf.size() * sizeof(float);
-        } else if (pc_mode == PcMode::ROI) {
-            const auto& objs = detector->objects();
-            for (const auto& obj : objs) {
-                int x1 = std::max(0, static_cast<int>(obj.bounding_box_2d[0]));
-                int y1 = std::max(0, static_cast<int>(obj.bounding_box_2d[1]));
-                int x2 = std::min(pc_width  - 1, static_cast<int>(obj.bounding_box_2d[4]));
-                int y2 = std::min(pc_height - 1, static_cast<int>(obj.bounding_box_2d[5]));
-                for (int y = y1; y <= y2; y++) {
-                    for (int x = x1; x <= x2; x++) {
-                        sl::float4 pt;
-                        point_cloud_mat.getValue(x, y, &pt);
-                        if (!std::isnan(pt.x) && !std::isinf(pt.x)) {
-                            pc_buf.push_back(pt.x); pc_buf.push_back(pt.y);
-                            pc_buf.push_back(pt.z); pc_buf.push_back(pt.w);
-                        }
-                    }
-                }
-            }
-            int N = static_cast<int>(pc_buf.size() / 4);
-            pc_metadata->set_string("layout", "NC");
-            pc_metadata->set_string("mode", "roi");
-            pc_metadata->set_list_int("shape", make_vector_int({N, 4}));
-            pc_data_ptr  = reinterpret_cast<const uint8_t*>(pc_buf.data());
-            pc_data_size = pc_buf.size() * sizeof(float);
-        } else {
-            // FULL — send raw sl::Mat pointer directly (no copy)
-            pc_data_size = static_cast<size_t>(pc_width * pc_height * sizeof(sl::float4));
-            pc_data_ptr  = reinterpret_cast<const uint8_t*>(point_cloud_mat.getPtr<sl::float4>());
-            pc_metadata->set_string("layout", "HWC");
-            pc_metadata->set_list_int("shape", make_shape(pc_height, pc_width, 4));
-        }
+            pc_metadata->set_list_int("shape",
+                                      make_vector_int({frame.pc_height, frame.pc_width, 4}));
+            set_intrinsics(*pc_metadata, frame.calib);
+            set_frame_stamps(*pc_metadata, frame);

-        rust::Slice<const uint8_t> pc_slice{pc_data_ptr, pc_data_size};
-        auto pc_result = send_output_with_metadata(
-            dora_node.send_output, "point_cloud", pc_slice, std::move(pc_metadata));
-        if (!std::string(pc_result.error).empty()) {
-            std::cerr << "Error sending point_cloud: " << std::string(pc_result.error) << std::endl;
+            send(dora_node, "point_cloud",
+                 arrow_c::float32(frame.point_cloud.data(), frame.point_cloud.size()),
+                 std::move(pc_metadata));
        }

        // --- camera_info ---
-        float camera_data[4] = {calib.fx, calib.fy, calib.cx, calib.cy};
-        rust::Slice<const uint8_t> cam_slice{
-            reinterpret_cast<const uint8_t*>(camera_data), sizeof(camera_data)};
+        if (frame.camera_info_first) {
+            const float camera_data[4] = {frame.calib.fx, frame.calib.fy, frame.calib.cx,
+                                          frame.calib.cy};

-        auto cam_metadata = new_metadata();
-        cam_metadata->set_string("dtype", "float32");
-        cam_metadata->set_string("layout", "C");
-        cam_metadata->set_list_int("shape", make_vector_int({4}));
-        cam_metadata->set_list_float("distortion", make_distortion(calib.distortion));
+            auto cam_metadata = new_metadata();
+            cam_metadata->set_list_float("distortion", make_distortion(frame.calib.distortion));
+            set_frame_stamps(*cam_metadata, frame);

-        auto cam_result = send_output_with_metadata(
-            dora_node.send_output, "camera_info", cam_slice, std::move(cam_metadata));
-        if (!std::string(cam_result.error).empty()) {
-            std::cerr << "Error sending camera_info: " << std::string(cam_result.error) << std::endl;
-        }
-
-        // --- objects ---
-        const auto& objects = detector->objects();
-        auto obj_buffer = serialize_objects(objects);
-        int num_objects = static_cast<int>(objects.size());
-
-        const size_t obj_size = obj_buffer.size() * sizeof(float);
-        rust::Slice<const uint8_t> obj_slice{
-            reinterpret_cast<const uint8_t*>(obj_buffer.data()), obj_size};
-
-        auto obj_metadata = new_metadata();
-        obj_metadata->set_string("dtype", "float32");
-        obj_metadata->set_string("layout", "RC");
-        obj_metadata->set_string("units", "mm");
-        obj_metadata->set_list_int("shape", make_vector_int({num_objects, FIELDS_PER_OBJECT}));
-        obj_metadata->set_string("fields",
-            "label_id,confidence,x,y,z,"
-            "bb2d_x0,bb2d_y0,bb2d_x1,bb2d_y1,bb2d_x2,bb2d_y2,bb2d_x3,bb2d_y3,"
-            "bb3d_x0,bb3d_y0,bb3d_z0,bb3d_x1,bb3d_y1,bb3d_z1,"
-            "bb3d_x2,bb3d_y2,bb3d_z2,bb3d_x3,bb3d_y3,bb3d_z3,"
-            "bb3d_x4,bb3d_y4,bb3d_z4,bb3d_x5,bb3d_y5,bb3d_z5,"
-            "bb3d_x6,bb3d_y6,bb3d_z6,bb3d_x7,bb3d_y7,bb3d_z7");
-        obj_metadata->set_string("label_names", detector->label_names());
-        obj_metadata->set_string("engine", engine_name);
-        obj_metadata->set_int("frame_id", current_frame_id);
-        obj_metadata->set_int("timestamp_ns", timestamp_ns);
-        obj_metadata->set_int("image_width", width);
-        obj_metadata->set_int("image_height", height);
-
-        auto obj_result = send_output_with_metadata(
-            dora_node.send_output, "objects", obj_slice, std::move(obj_metadata));
-        if (!std::string(obj_result.error).empty()) {
-            std::cerr << "Error sending objects: " << std::string(obj_result.error) << std::endl;
+            send(dora_node, "camera_info", arrow_c::float32(camera_data, 4),
+                 std::move(cam_metadata));
        }
    }

+    capture.stop();
+    if (!capture.wait_exit(std::chrono::seconds(2))) {
+        // The capture thread is inside a blocking SDK call, where nothing can
+        // reach it. Leave rather than let dora wait out its grace period and kill
+        // the node: the frames are gone either way, and Stop has been answered.
+        std::cerr << "capture thread still in the SDK; exiting anyway" << std::endl;
+        std::cout.flush();
+        std::_Exit(0);
+    }
    return 0;
 }
@@ -1,113 +0,0 @@
-// Standalone test for the YoloOnnx (closed-vocabulary) detection engine.
-// No dora framework, no live ZED camera — loads an image from disk.
-//
-// Usage:
-//   bin/test_yolo_onnx [image_path]
-//   image_path   default: test/assets/yolo.png
-//
-// Required env vars:
-//   ZED_ONNX_MODEL_PATH        path to YOLO ONNX model
-//
-// Optional env vars:
-//   ZED_ONNX_LABELS            comma-separated class names
-//   ZED_ONNX_LABELS_FILE       path to newline-separated class names file
-//   ZED_ONNX_CONFIDENCE        detection threshold (default 0.25)
-//   ZED_ONNX_NMS_THRESHOLD     NMS IoU threshold (default 0.45)
-//   ZED_ONNX_INPUT_SIZE        model input size (default 640)
-//   ZED_ONNX_OUTPUT_FORMAT     nc_first|nc_last|nc_last_obj|yolov5|yolov8|yolov11|auto
-
-#include "engines/yolo_onnx.h"
-#include "util/env.h"
-
-#include <opencv2/opencv.hpp>
-#include <sl/Camera.hpp>
-
-#include <filesystem>
-#include <iostream>
-#include <sstream>
-#include <string>
-#include <vector>
-
-namespace fs = std::filesystem;
-
-namespace {
-
-std::vector<std::string> parse_csv(const std::string& s) {
-    std::vector<std::string> out;
-    std::istringstream ss(s);
-    std::string tok;
-    while (std::getline(ss, tok, ',')) {
-        size_t l = tok.find_first_not_of(" \t");
-        size_t r = tok.find_last_not_of(" \t");
-        if (l != std::string::npos)
-            out.push_back(tok.substr(l, r - l + 1));
-    }
-    return out;
-}
-
-void draw_detections(cv::Mat& img,
-                     const std::vector<engines::DetectedObject>& objects,
-                     const std::vector<std::string>& labels) {
-    for (const auto& obj : objects) {
-        int x1 = static_cast<int>(obj.bounding_box_2d[0]);
-        int y1 = static_cast<int>(obj.bounding_box_2d[1]);
-        int x2 = static_cast<int>(obj.bounding_box_2d[4]);
-        int y2 = static_cast<int>(obj.bounding_box_2d[5]);
-
-        std::string name = (obj.label_id >= 0 && obj.label_id < static_cast<int>(labels.size()))
-                           ? labels[obj.label_id] : std::to_string(obj.label_id);
-
-        char buf[64];
-        std::snprintf(buf, sizeof(buf), " %.2f", obj.confidence / 100.0f);
-
-        cv::rectangle(img, {x1, y1}, {x2, y2}, {0, 200, 0}, 2);
-        cv::putText(img, name + buf, {x1, std::max(y1 - 6, 14)},
-                    cv::FONT_HERSHEY_SIMPLEX, 0.55, {0, 200, 0}, 2, cv::LINE_AA);
-    }
-}
-
-} // namespace
-
-int main(int argc, char* argv[]) {
-    std::string image_path = (argc > 1) ? argv[1] : "test/assets/yolo.png";
-
-    auto config = engines::YoloOnnxConfig::from_env();
-
-    sl::Camera dummy_cam;
-    engines::YoloOnnx engine(config);
-    engine.enable(dummy_cam);
-
-    cv::Mat img = cv::imread(image_path);
-    if (img.empty()) {
-        std::cerr << "Error: cannot read image: " << image_path << std::endl;
-        return 1;
-    }
-
-    engine.detect(img);
-    const auto& objects = engine.objects();
-    auto labels = parse_csv(engine.label_names());
-
-    std::cout << "[" << image_path << "] " << objects.size() << " detection(s):" << std::endl;
-    for (const auto& obj : objects) {
-        std::string name = (obj.label_id >= 0 && obj.label_id < static_cast<int>(labels.size()))
-                           ? labels[obj.label_id] : std::to_string(obj.label_id);
-        std::cout << "  " << name
-                  << "  conf=" << obj.confidence / 100.0f
-                  << "  bbox=["
-                  << obj.bounding_box_2d[0] << "," << obj.bounding_box_2d[1]
-                  << " -> "
-                  << obj.bounding_box_2d[4] << "," << obj.bounding_box_2d[5]
-                  << "]" << std::endl;
-    }
-
-    cv::Mat annotated = img.clone();
-    draw_detections(annotated, objects, labels);
-
-    fs::path stem   = fs::path(image_path).stem();
-    fs::path parent = fs::path(image_path).parent_path();
-    std::string result_path = (parent / (stem.string() + "_result.png")).string();
-    cv::imwrite(result_path, annotated);
-    std::cout << "Saved: " << result_path << std::endl;
-
-    return 0;
-}
@@ -1,11 +1,12 @@
 #include "zed/camera.h"
 #include "util/env.h"

-#include <chrono>
+#include <algorithm>
+#include <cstdlib>
 #include <iostream>
 #include <iterator>
 #include <string>
-#include <thread>
+#include <utility>

 namespace {

@@ -21,17 +22,30 @@ sl::RESOLUTION parse_resolution(int resolution) {
    }
 }

+const std::pair<const char*, sl::DEPTH_MODE> DEPTH_MODES[] = {
+    {"NEURAL", sl::DEPTH_MODE::NEURAL},
+    {"NEURAL_PLUS", sl::DEPTH_MODE::NEURAL_PLUS},
+    {"NEURAL_LIGHT", sl::DEPTH_MODE::NEURAL_LIGHT},
+    {"PERFORMANCE", sl::DEPTH_MODE::PERFORMANCE},
+    {"QUALITY", sl::DEPTH_MODE::QUALITY},
+    {"NONE", sl::DEPTH_MODE::NONE},
+};
+
+// A typo here silently changes depth quality if it falls back to a default, and
+// the resulting depth is wrong in a way that only shows up downstream, so an
+// unrecognised name stops the node instead.
 sl::DEPTH_MODE parse_depth_mode(const std::string& mode) {
-    if (mode == "PERFORMANCE") {
-        return sl::DEPTH_MODE::PERFORMANCE;
+    for (const auto& entry : DEPTH_MODES) {
+        if (mode == entry.first) {
+            return entry.second;
+        }
    }
-    if (mode == "QUALITY") {
-        return sl::DEPTH_MODE::QUALITY;
+    std::cerr << "Unknown ZED_DEPTH_MODE '" << mode << "'. Accepted values:";
+    for (const auto& entry : DEPTH_MODES) {
+        std::cerr << " " << entry.first;
    }
-    if (mode == "NONE") {
-        return sl::DEPTH_MODE::NONE;
-    }
-    return sl::DEPTH_MODE::NEURAL;
+    std::cerr << std::endl;
+    std::exit(1);
 }

 sl::FLIP_MODE parse_flip(const std::string& mode) {
@@ -41,6 +55,24 @@ sl::FLIP_MODE parse_flip(const std::string& mode) {
    return sl::FLIP_MODE::ON;
 }

+// A blank frame is checked on a strided sample rather than the full image, which
+// is just as conclusive and costs nothing at frame rate.
+constexpr int BLANK_FRAME_STRIDE = 16;
+
+// sl::Camera::reboot() reaches the ZED 2 and newer. On the first-generation ZED
+// and the ZED Mini it returns without touching the device, so calling it there
+// only costs time and fills the log.
+bool model_supports_reboot(sl::MODEL model) {
+    return model != sl::MODEL::ZED && model != sl::MODEL::ZED_M;
+}
+
+// The SDK reconnects a camera whose link hiccuped by itself. Dropping the handle
+// over one of these takes the recovery away from the SDK and hands it to us,
+// which is slower and, on a device the kernel is about to suspend, often fatal.
+bool is_transient_grab_error(sl::ERROR_CODE err) {
+    return err == sl::ERROR_CODE::CAMERA_REBOOTING || err == sl::ERROR_CODE::CORRUPTED_FRAME;
+}
+
 void list_available_cameras() {
    auto devices = sl::Camera::getDeviceList();
    std::cout << "Detected ZED cameras: " << devices.size() << std::endl;
@@ -59,50 +91,112 @@ Config Config::from_env() {
    Config c;
    c.resolution = util::get_env_int("ZED_RESOLUTION", c.resolution);
    c.fps = util::get_env_int("ZED_FPS", c.fps);
-    c.depth_mode = util::get_env_str("ZED_DEPTH_MODE", c.depth_mode);
+    c.depth_mode = parse_depth_mode(util::get_env_str("ZED_DEPTH_MODE", "NEURAL"));
    c.depth_min_mm = util::get_env_int("ZED_DEPTH_MIN_MM", c.depth_min_mm);
    c.depth_max_mm = util::get_env_int("ZED_DEPTH_MAX_MM", c.depth_max_mm);
    c.depth_fill = util::get_env_bool("ZED_DEPTH_FILL", c.depth_fill);
+    c.point_cloud = util::get_env_bool("ZED_POINT_CLOUD", c.point_cloud);
+    c.pc_mode = util::get_env_str("ZED_PC_MODE", "FULL") == "HALF" ? PcMode::HALF : PcMode::FULL;
+    c.confidence_threshold = util::get_env_int("ZED_CONFIDENCE_THRESHOLD", c.confidence_threshold);
+    c.texture_confidence_threshold =
+        util::get_env_int("ZED_TEXTURE_CONFIDENCE_THRESHOLD", c.texture_confidence_threshold);
    c.flip = util::get_env_str("ZED_FLIP", c.flip);
    c.warmup_frames = util::get_env_int("ZED_WARMUP_FRAMES", c.warmup_frames);
-    int retry_seconds = util::get_env_int("ZED_RETRY_INTERVAL_SECONDS", 5);
-    c.retry_interval_ms = retry_seconds * 1000;
    return c;
 }

 Camera::Camera(const Config& config) : config_(config) {
+    // Process-wide, and must be set before any camera is opened. Without it the
+    // epoch of the timestamps published alongside every frame depends on the SDK
+    // default rather than on anything this node states.
+    sl::setTimestampClock(sl::TIMESTAMP_CLOCK::SYSTEM_CLOCK);
+
    init_params_.camera_resolution = parse_resolution(config_.resolution);
    init_params_.camera_fps = config_.fps;
-    init_params_.depth_mode = parse_depth_mode(config_.depth_mode);
+    init_params_.depth_mode = config_.depth_mode;
    init_params_.coordinate_units = sl::UNIT::MILLIMETER;
    init_params_.camera_image_flip = parse_flip(config_.flip);
    init_params_.depth_minimum_distance = config_.depth_min_mm;
    init_params_.depth_maximum_distance = config_.depth_max_mm;
+    // Recover a hiccuping link inside the SDK rather than out here. Without this
+    // a grab blocks for the roughly 17 s the SDK spends reconnecting, freezing the
+    // dora event loop; with it the grab returns CAMERA_REBOOTING straight away and
+    // the SDK reconnects in the background, holding the device open meanwhile.
+    init_params_.async_grab_camera_recovery = true;
+    // Let the SDK flag the frames a stalled camera hands back looking valid.
+    init_params_.enable_image_validity_check = 1;

    runtime_params_.enable_depth = true;
    runtime_params_.enable_fill_mode = config_.depth_fill;
+    // The two thresholds discard the depth the SDK is least certain of, which is
+    // the depth at object edges: those pixels straddle the object and whatever is
+    // behind it, and belong to neither.
+    runtime_params_.confidence_threshold = config_.confidence_threshold;
+    runtime_params_.texture_confidence_threshold = config_.texture_confidence_threshold;
+
+    std::cout << "ZED depth: mode=" << sl::toString(init_params_.depth_mode)
+              << ", range=" << config_.depth_min_mm << "-" << config_.depth_max_mm << " mm"
+              << ", confidence=" << config_.confidence_threshold
+              << ", texture_confidence=" << config_.texture_confidence_threshold
+              << ", fill=" << (config_.depth_fill ? "on" : "off") << std::endl;
+
+    list_available_cameras();
 }

 Camera::~Camera() {
    close();
 }

-void Camera::open() {
-    list_available_cameras();
-    while (true) {
-        sl::ERROR_CODE err = zed_.open(init_params_);
-        if (err == sl::ERROR_CODE::SUCCESS) {
-            return;
-        }
+bool Camera::open() {
+    sl::ERROR_CODE err = zed_.open(init_params_);
+    if (err != sl::ERROR_CODE::SUCCESS) {
        std::cerr << "Failed to open ZED camera: " << sl::toString(err) << std::endl;
-        std::this_thread::sleep_for(std::chrono::milliseconds(config_.retry_interval_ms));
+        return false;
    }
+    recovering_ = false;
+
+    sl::CameraInformation info = zed_.getCameraInformation();
+    serial_number_ = info.serial_number;
+    model_ = info.camera_model;
+    // After the first open, reopen the same physical camera. Recovery runs while
+    // the device may be mid-re-enumeration, and picking whichever ZED answers
+    // first is not the same thing as picking ours.
+    init_params_.input.setFromSerialNumber(serial_number_);
+
+    std::cout << "ZED camera opened (" << sl::toString(model_) << ", SN " << serial_number_ << ")"
+              << std::endl;
+    return true;
 }

 void Camera::close() {
+    recovering_ = false;
    zed_.close();
 }

+void Camera::reset() {
+    close();
+    if (serial_number_ == 0 || !model_supports_reboot(model_)) {
+        return;
+    }
+    // The ZED can stop delivering frames while staying enumerated: the video
+    // endpoint halts, grabs fail, and reopening returns CAMERA FAILED TO SETUP
+    // because the endpoint is still halted. A device reset clears that, and
+    // reboot() is the SDK's way to ask for one without unplugging the camera.
+    // The device re-enumerates afterwards, so the caller's backoff before the
+    // next open is what lets it settle.
+    sl::ERROR_CODE err = sl::Camera::reboot(static_cast<int>(serial_number_), true);
+    std::cout << "reset ZED camera (SN " << serial_number_ << "): " << sl::toString(err)
+              << std::endl;
+}
+
+bool Camera::is_open() const {
+    return zed_.isOpened();
+}
+
+bool Camera::recovering() const {
+    return recovering_;
+}
+
 void Camera::warmup() {
    for (int i = 0; i < config_.warmup_frames; i++) {
        zed_.grab(runtime_params_);
@@ -110,11 +204,34 @@ void Camera::warmup() {
 }

 bool Camera::grab() {
-    if (zed_.grab(runtime_params_) != sl::ERROR_CODE::SUCCESS) {
+    sl::ERROR_CODE err = zed_.grab(runtime_params_);
+    if (err != sl::ERROR_CODE::SUCCESS) {
+        if (is_transient_grab_error(err)) {
+            // Every grab repeats this for as long as the reconnect takes, so only
+            // the first one is worth a line in the log.
+            if (!recovering_) {
+                recovering_ = true;
+                std::cerr << "ZED camera link dropped (" << sl::toString(err)
+                          << "); the SDK is reconnecting it" << std::endl;
+            }
+        } else {
+            recovering_ = false;
+            std::cerr << "Failed to grab frame: " << sl::toString(err) << std::endl;
+        }
        return false;
    }
+    if (recovering_) {
+        recovering_ = false;
+        std::cout << "ZED camera link restored" << std::endl;
+    }
+
    zed_.retrieveImage(image_mat_, sl::VIEW::LEFT);
-    zed_.retrieveMeasure(point_cloud_mat_, sl::MEASURE::XYZRGBA);
+    zed_.retrieveMeasure(depth_mat_, sl::MEASURE::DEPTH);
+    // At 1080p a full XYZRGBA cloud is ~14.7 MB per frame, and retrieving it
+    // costs capture time whether or not anything consumes it.
+    if (config_.point_cloud) {
+        zed_.retrieveMeasure(point_cloud_mat_, sl::MEASURE::XYZRGBA);
+    }
    return true;
 }

@@ -135,16 +252,48 @@ Calibration Camera::calibration() const {
    return result;
 }

+bool Camera::image_is_blank() {
+    const int height = image_mat_.getHeight();
+    const int width = image_mat_.getWidth();
+    if (height == 0 || width == 0) {
+        return true;
+    }
+
+    const size_t step = image_mat_.getStep(sl::MEM::CPU);
+    const sl::uchar4* src = image_mat_.getPtr<sl::uchar4>();
+
+    unsigned char lowest[3] = {255, 255, 255};
+    unsigned char highest[3] = {0, 0, 0};
+    for (int y = 0; y < height; y += BLANK_FRAME_STRIDE) {
+        const sl::uchar4* row = src + static_cast<size_t>(y) * step;
+        for (int x = 0; x < width; x += BLANK_FRAME_STRIDE) {
+            const unsigned char channels[3] = {row[x].x, row[x].y, row[x].z};
+            for (int c = 0; c < 3; c++) {
+                lowest[c] = std::min(lowest[c], channels[c]);
+                highest[c] = std::max(highest[c], channels[c]);
+            }
+        }
+    }
+    // Sensor noise makes a single-colour frame impossible for a live camera, so
+    // this tells a dead device apart from any real scene.
+    return lowest[0] == highest[0] && lowest[1] == highest[1] && lowest[2] == highest[2];
+}
+
+int64_t Camera::device_timestamp_ns() {
+    return static_cast<int64_t>(
+        zed_.getTimestamp(sl::TIME_REFERENCE::IMAGE).getNanoseconds());
+}
+
 sl::Mat& Camera::image() {
    return image_mat_;
 }

+sl::Mat& Camera::depth() {
+    return depth_mat_;
+}
+
 sl::Mat& Camera::point_cloud() {
    return point_cloud_mat_;
 }

-sl::Camera& Camera::handle() {
-    return zed_;
-}
-
 } // namespace zed
@@ -1,27 +1,33 @@
 #pragma once

 #include <sl/Camera.hpp>
+#include <cstdint>
 #include <string>
 #include <vector>

 namespace zed {

+enum class PcMode { FULL, HALF };
+
 struct Config {
-    int resolution = 720;
+    int resolution = 1080;
    int fps = 15;
-    std::string depth_mode = "NEURAL";
-    int depth_min_mm = 10;
-    int depth_max_mm = 500;
+    sl::DEPTH_MODE depth_mode = sl::DEPTH_MODE::NEURAL;
+    int depth_min_mm = 200;
+    int depth_max_mm = 600;
    bool depth_fill = false;
+    bool point_cloud = false;
+    PcMode pc_mode = PcMode::FULL;
+    int confidence_threshold = 60;
+    int texture_confidence_threshold = 100;
    std::string flip = "ON";
    int warmup_frames = 30;
-    int retry_interval_ms = 5000;

    static Config from_env();
 };

 struct Calibration {
-    float fx, fy, cx, cy;
+    float fx = 0, fy = 0, cx = 0, cy = 0;
    std::vector<double> distortion;
 };

@@ -30,14 +36,26 @@ public:
    explicit Camera(const Config& config);
    ~Camera();

-    void open();
+    // One attempt, returning whether it succeeded. The caller decides when to try
+    // again, so a camera that is down never blocks the dora event loop.
+    bool open();
    void close();
+    // Close the handle and reset the device over USB, where the model allows it.
+    void reset();
    void warmup();
    bool grab();
+    bool is_open() const;
+    // True while the SDK is reconnecting the camera after a link hiccup.
+    bool recovering() const;
+    // True when the last grabbed frame carries no picture at all. A camera whose
+    // link has dropped does not necessarily fail its grabs: it can keep reporting
+    // success and hand back a uniform frame.
+    bool image_is_blank();
    Calibration calibration() const;
+    int64_t device_timestamp_ns();
    sl::Mat& image();
+    sl::Mat& depth();
    sl::Mat& point_cloud();
-    sl::Camera& handle();

 private:
    Config config_;
@@ -45,7 +63,13 @@ private:
    sl::InitParameters init_params_;
    sl::RuntimeParameters runtime_params_;
    sl::Mat image_mat_;
+    sl::Mat depth_mat_;
    sl::Mat point_cloud_mat_;
+    // Read off the device once it is open and kept afterwards: resetting a wedged
+    // camera needs the serial and the model, and by then the handle is gone.
+    unsigned int serial_number_ = 0;
+    sl::MODEL model_ = sl::MODEL::LAST;
+    bool recovering_ = false;
 };

 } // namespace zed
@@ -0,0 +1,302 @@
+#include "zed/capture.h"
+
+#include <opencv2/opencv.hpp>
+
+#include <algorithm>
+#include <chrono>
+#include <cmath>
+#include <iostream>
+
+namespace {
+
+using Clock = std::chrono::steady_clock;
+
+// Going this long without a usable frame means the camera is wedged rather than
+// dropping the odd frame. Measured in elapsed time rather than in failed grabs,
+// because a stalling camera can spend seconds inside a single grab.
+constexpr double STALL_TIMEOUT_S = 5.0;
+
+// How long the SDK is left to reconnect the camera on its own before the loop
+// stops waiting on it and rebuilds the camera anyway. A driver that says it is
+// recovering is usually right, but it has no way to tell us it has given up.
+constexpr double DRIVER_RECOVERY_TIMEOUT_S = 30.0;
+
+// How long to wait between grabs while the camera is not delivering.
+constexpr std::chrono::milliseconds GRAB_RETRY{500};
+
+// How long to wait before each reopen: one entry per attempt, the last repeated
+// for every attempt beyond it.
+constexpr int REOPEN_BACKOFF_S[] = {1, 2, 5, 10};
+
+std::chrono::seconds reopen_backoff(int attempt) {
+    const size_t index = std::min(static_cast<size_t>(attempt), std::size(REOPEN_BACKOFF_S)) - 1;
+    return std::chrono::seconds(REOPEN_BACKOFF_S[index]);
+}
+
+double seconds_since(Clock::time_point since) {
+    return std::chrono::duration<double>(Clock::now() - since).count();
+}
+
+int64_t host_timestamp_ns() {
+    return std::chrono::duration_cast<std::chrono::nanoseconds>(
+               std::chrono::system_clock::now().time_since_epoch())
+        .count();
+}
+
+// Copy the depth map into a tightly packed [H, W] buffer of millimetres.
+//
+// The rows of an sl::Mat can be padded, so the buffer is not necessarily H * W
+// floats. inf and nan mark depth the SDK could not measure; they are cleared to
+// 0 here, as the reference driver does, because a hole is meaningful and a
+// consumer cannot back-project a non-finite value.
+void pack_depth(sl::Mat& depth_mat, std::vector<float>& out) {
+    const int height = depth_mat.getHeight();
+    const int width = depth_mat.getWidth();
+    const size_t step = depth_mat.getStep(sl::MEM::CPU);
+    const float* src = depth_mat.getPtr<sl::float1>();
+
+    out.resize(static_cast<size_t>(height) * static_cast<size_t>(width));
+    for (int y = 0; y < height; y++) {
+        const float* row = src + static_cast<size_t>(y) * step;
+        float* dst = out.data() + static_cast<size_t>(y) * static_cast<size_t>(width);
+        for (int x = 0; x < width; x++) {
+            dst[x] = std::isfinite(row[x]) ? row[x] : 0.0f;
+        }
+    }
+}
+
+} // namespace
+
+namespace zed {
+
+Capture::Capture(const Config& config) : config_(config), camera_(config) {}
+
+Capture::~Capture() {
+    stop();
+    if (thread_.joinable()) {
+        // The thread may still be inside the SDK. Detaching leaks it for the few
+        // moments the process has left, which is preferable to blocking here.
+        if (wait_exit(std::chrono::seconds(1))) {
+            thread_.join();
+        } else {
+            thread_.detach();
+        }
+    }
+}
+
+void Capture::start() {
+    {
+        std::lock_guard<std::mutex> lock(mutex_);
+        running_ = true;
+    }
+    thread_ = std::thread(&Capture::run, this);
+}
+
+void Capture::stop() {
+    std::lock_guard<std::mutex> lock(mutex_);
+    running_ = false;
+    wake_.notify_all();
+}
+
+bool Capture::wait_exit(std::chrono::milliseconds timeout) {
+    std::unique_lock<std::mutex> lock(mutex_);
+    return exited_.wait_for(lock, timeout, [this] { return finished_; });
+}
+
+bool Capture::take_frame(Frame& out) {
+    std::lock_guard<std::mutex> lock(mutex_);
+    if (!has_frame_) {
+        return false;
+    }
+    std::swap(out, latest_);
+    has_frame_ = false;
+    return true;
+}
+
+bool Capture::take_state_change(std::string& out) {
+    std::lock_guard<std::mutex> lock(mutex_);
+    if (!state_changed_) {
+        return false;
+    }
+    out = state_;
+    state_changed_ = false;
+    return true;
+}
+
+void Capture::set_state(const char* state) {
+    std::lock_guard<std::mutex> lock(mutex_);
+    if (state_ == state) {
+        return;
+    }
+    state_ = state;
+    state_changed_ = true;
+    std::cout << "camera state: " << state_ << std::endl;
+}
+
+void Capture::sleep_interruptible(std::chrono::milliseconds duration) {
+    std::unique_lock<std::mutex> lock(mutex_);
+    wake_.wait_for(lock, duration, [this] { return !running_; });
+}
+
+void Capture::begin_recovery(int attempt) {
+    // The first attempt only closes the handle, which is enough when the driver
+    // rather than the device lost its way; past that the device itself is wedged
+    // and nothing short of resetting it will bring the frames back.
+    if (attempt <= 1) {
+        camera_.close();
+    } else {
+        camera_.reset();
+    }
+    const auto wait = reopen_backoff(attempt);
+    std::cerr << "recovering camera (attempt " << attempt << "); next open in " << wait.count()
+              << "s" << std::endl;
+    sleep_interruptible(std::chrono::duration_cast<std::chrono::milliseconds>(wait));
+}
+
+void Capture::pack_frame(Frame& frame, int64_t frame_id, bool camera_info_first) {
+    sl::Mat& image_mat = camera_.image();
+    const int width = image_mat.getWidth();
+    const int height = image_mat.getHeight();
+
+    frame.frame_id = frame_id;
+    frame.device_ns = camera_.device_timestamp_ns();
+    frame.host_ns = host_timestamp_ns();
+    frame.width = width;
+    frame.height = height;
+    frame.calib = camera_.calibration();
+    frame.camera_info_first = camera_info_first;
+
+    cv::Mat image_rgba(height, width, CV_8UC4, image_mat.getPtr<sl::uchar1>(),
+                       image_mat.getStep(sl::MEM::CPU) * sizeof(sl::uchar4));
+    frame.image_bgr.resize(static_cast<size_t>(height) * width * 3);
+    cv::Mat image_bgr(height, width, CV_8UC3, frame.image_bgr.data());
+    cv::cvtColor(image_rgba, image_bgr, cv::COLOR_BGRA2BGR);
+
+    pack_depth(camera_.depth(), frame.depth);
+
+    frame.has_point_cloud = config_.point_cloud;
+    if (!frame.has_point_cloud) {
+        return;
+    }
+
+    // Unlike the image and depth, the cloud used to be published straight from
+    // the SDK buffer. It has to be copied now that the reader is another thread.
+    sl::Mat& pc_mat = camera_.point_cloud();
+    const int pc_width = pc_mat.getWidth();
+    const int pc_height = pc_mat.getHeight();
+    const size_t pc_step = pc_mat.getStep(sl::MEM::CPU);
+    const sl::float4* src = pc_mat.getPtr<sl::float4>();
+
+    const int stride = config_.pc_mode == PcMode::HALF ? 2 : 1;
+    frame.pc_width = pc_width / stride;
+    frame.pc_height = pc_height / stride;
+    frame.point_cloud.resize(static_cast<size_t>(frame.pc_height) * frame.pc_width * 4);
+
+    for (int y = 0; y < frame.pc_height; y++) {
+        const sl::float4* row = src + static_cast<size_t>(y * stride) * pc_step;
+        float* dst = frame.point_cloud.data() + static_cast<size_t>(y) * frame.pc_width * 4;
+        for (int x = 0; x < frame.pc_width; x++) {
+            const sl::float4& point = row[x * stride];
+            dst[x * 4 + 0] = point.x;
+            dst[x * 4 + 1] = point.y;
+            dst[x * 4 + 2] = point.z;
+            dst[x * 4 + 3] = point.w;
+        }
+    }
+}
+
+void Capture::run() {
+    int recovery_attempts = 0;
+    bool streamed_once = false;
+    bool stall_reported = false;
+    bool camera_info_pending = false;
+    auto last_good_frame_at = Clock::now();
+    int64_t frame_id = 0;
+
+    set_state("opening");
+
+    while (true) {
+        {
+            std::lock_guard<std::mutex> lock(mutex_);
+            if (!running_) {
+                break;
+            }
+        }
+
+        const char* down_state = streamed_once ? "recovering" : "opening";
+
+        if (!camera_.is_open()) {
+            set_state(down_state);
+            if (!camera_.open()) {
+                recovery_attempts++;
+                begin_recovery(recovery_attempts);
+                continue;
+            }
+            // Discard the first frames so auto-exposure settles. This blocks, and
+            // on this thread that is fine.
+            camera_.warmup();
+            camera_info_pending = true;
+            // Opening the ZED takes seconds. Start the stall clock from here so
+            // that cost is never mistaken for a stalled stream.
+            last_good_frame_at = Clock::now();
+            // recovery_attempts is deliberately not cleared here. A wedged device
+            // can open and still deliver nothing; clearing on open would restart
+            // the escalation ladder every cycle and never reach the reset.
+            continue;
+        }
+
+        // A blank frame counts as a failed grab: a camera whose link has dropped
+        // does not necessarily fail its grabs, it can keep reporting success and
+        // hand back a uniform frame with an empty depth map.
+        if (!camera_.grab() || camera_.image_is_blank()) {
+            set_state(down_state);
+            const double stalled_for = seconds_since(last_good_frame_at);
+            // The SDK holds the camera open while it reconnects a dropped link.
+            // Taking the handle away mid-reconnect aborts that and leaves us to
+            // redo it the slow way, so it gets longer than a plain stall.
+            const double patience =
+                camera_.recovering() ? DRIVER_RECOVERY_TIMEOUT_S : STALL_TIMEOUT_S;
+            if (stalled_for < patience) {
+                sleep_interruptible(GRAB_RETRY);
+                continue;
+            }
+            if (!stall_reported) {
+                stall_reported = true;
+                std::cerr << "camera delivered no usable frame for " << stalled_for << "s"
+                          << std::endl;
+            }
+            recovery_attempts++;
+            begin_recovery(recovery_attempts);
+            continue;
+        }
+
+        if (stall_reported) {
+            std::cout << "camera recovered after " << recovery_attempts << " attempt(s)"
+                      << std::endl;
+            stall_reported = false;
+        }
+        last_good_frame_at = Clock::now();
+        recovery_attempts = 0;
+        streamed_once = true;
+
+        pack_frame(scratch_, frame_id++, camera_info_pending);
+        camera_info_pending = false;
+        {
+            std::lock_guard<std::mutex> lock(mutex_);
+            // Swapping rather than assigning hands the previous frame's buffers
+            // back, so steady-state capture does not reallocate.
+            std::swap(latest_, scratch_);
+            has_frame_ = true;
+        }
+        set_state("streaming");
+    }
+
+    camera_.close();
+    {
+        std::lock_guard<std::mutex> lock(mutex_);
+        finished_ = true;
+        exited_.notify_all();
+    }
+}
+
+} // namespace zed
@@ -0,0 +1,94 @@
+#pragma once
+
+#include "zed/camera.h"
+
+#include <condition_variable>
+#include <cstdint>
+#include <mutex>
+#include <string>
+#include <thread>
+#include <vector>
+
+namespace zed {
+
+// One captured frame, owning its buffers.
+//
+// The SDK reuses its own buffers on the next grab, so nothing here can point
+// into an sl::Mat: the capture thread copies every payload out before handing
+// the frame over.
+struct Frame {
+    int64_t frame_id = 0;
+    int64_t device_ns = 0;
+    int64_t host_ns = 0;
+    int width = 0;
+    int height = 0;
+    std::vector<uint8_t> image_bgr; // height * width * 3
+    std::vector<float> depth;       // height * width, millimetres
+    bool has_point_cloud = false;
+    int pc_width = 0;
+    int pc_height = 0;
+    std::vector<float> point_cloud; // pc_height * pc_width * 4
+    Calibration calib;
+    // Set on the first frame of a camera session, so camera_info is published
+    // once per session rather than per frame.
+    bool camera_info_first = false;
+};
+
+// Owns the camera on its own thread and hands the newest frame to the reader.
+//
+// The ZED SDK can block for an unbounded time inside grab() and open() — a
+// disconnected camera has been measured blocking indefinitely, even with
+// InitParameters::async_grab_camera_recovery set. Driving the camera from the
+// dora event loop therefore froze the node: it stopped reading events, so Stop
+// went unanswered and the recovery logic itself was never reached. Everything
+// that can block lives on this thread instead, and the event loop only ever
+// touches the buffer below.
+class Capture {
+public:
+    explicit Capture(const Config& config);
+    ~Capture();
+
+    void start();
+    // Ask the thread to finish. Returns immediately: the thread may be inside a
+    // blocking SDK call and cannot be interrupted there.
+    void stop();
+    // Wait for the thread to actually leave, up to timeout. False means it is
+    // still stuck in the SDK.
+    bool wait_exit(std::chrono::milliseconds timeout);
+
+    // Move the newest frame out, if one arrived since the last call. Frames that
+    // are not collected are overwritten: the reader always wants the latest.
+    bool take_frame(Frame& out);
+    // Report the camera state, if it changed since the last call.
+    bool take_state_change(std::string& out);
+
+private:
+    void run();
+    void set_state(const char* state);
+    // Release the camera and wait out the backoff for this attempt. The wait is
+    // interruptible, so stop() is honoured while the camera is down.
+    void begin_recovery(int attempt);
+    void sleep_interruptible(std::chrono::milliseconds duration);
+    void pack_frame(Frame& frame, int64_t frame_id, bool camera_info_first);
+
+    Config config_;
+    Camera camera_;
+    std::thread thread_;
+
+    std::mutex mutex_;
+    std::condition_variable wake_;
+    std::condition_variable exited_;
+    bool running_ = false;
+    bool finished_ = false;
+
+    Frame latest_;
+    // Holds the previously published frame once the reader has taken the newest
+    // one, so its buffers are reused instead of reallocated every frame.
+    Frame scratch_;
+    bool has_frame_ = false;
+
+    std::string state_;
+    bool state_changed_ = false;
+};
+
+} // namespace zed
@@ -0,0 +1,36 @@
+// C entry points for tests/test_arrow.py.
+//
+// The Python side cannot call the C++ builders, so each one is wrapped here and
+// the payload is passed in from the test rather than fixed in this file.
+
+#include "arrow/array.h"
+
+#include <cstring>
+
+namespace {
+
+void hand_over(void* array, void* schema, const arrow_c::Exported& exported) {
+    // The caller owns the two structs, exactly as dora does: it reads them and
+    // is then responsible for releasing what they point at.
+    std::memcpy(array, &exported.array, sizeof(exported.array));
+    std::memcpy(schema, &exported.schema, sizeof(exported.schema));
+}
+
+} // namespace
+
+extern "C" {
+
+void zed_export_image(void* array, void* schema, uint32_t width, uint32_t height,
+                      const char* encoding, const uint8_t* data, size_t size) {
+    hand_over(array, schema, arrow_c::image(width, height, encoding, data, size));
+}
+
+void zed_export_float32(void* array, void* schema, const float* values, size_t count) {
+    hand_over(array, schema, arrow_c::float32(values, count));
+}
+
+void zed_export_string(void* array, void* schema, const char* text, size_t size) {
+    hand_over(array, schema, arrow_c::string(text, size));
+}
+
+} // extern "C"
@@ -0,0 +1,54 @@
+// Release has to free the whole tree: the array nodes, the schema nodes, and
+// the storage their buffers point into. Nothing here asserts that directly -
+// the sanitizers tests/run.sh builds this with are the assertion, and a node
+// that leaks per frame is a node that dies on a long run.
+
+#include "arrow/array.h"
+
+#include <cassert>
+#include <cstdint>
+#include <string>
+#include <vector>
+
+namespace {
+
+void release(arrow_c::Exported& exported) {
+    exported.array.release(&exported.array);
+    exported.schema.release(&exported.schema);
+
+    // A released struct marks itself, which is how a consumer knows not to
+    // release it twice.
+    assert(exported.array.release == nullptr);
+    assert(exported.schema.release == nullptr);
+}
+
+} // namespace
+
+int main() {
+    const std::vector<uint8_t> pixels(4 * 4 * 3, 7);
+    const std::vector<float> depth(4 * 4, 1500.0F);
+    const std::string state = "streaming";
+
+    for (int i = 0; i < 100; ++i) {
+        arrow_c::Exported image =
+            arrow_c::image(4, 4, "bgr8", pixels.data(), pixels.size());
+        assert(image.array.length == 1);
+        assert(image.array.n_children == 4);
+        release(image);
+
+        arrow_c::Exported depth_image =
+            arrow_c::image(4, 4, "32FC1", reinterpret_cast<const uint8_t*>(depth.data()),
+                           depth.size() * sizeof(float));
+        release(depth_image);
+
+        arrow_c::Exported values = arrow_c::float32(depth.data(), depth.size());
+        assert(values.array.length == static_cast<int64_t>(depth.size()));
+        release(values);
+
+        arrow_c::Exported text = arrow_c::string(state.data(), state.size());
+        assert(text.array.length == 1);
+        release(text);
+    }
+
+    return 0;
+}
@@ -0,0 +1,29 @@
+#!/usr/bin/env bash
+# Build and run the payload tests.
+#
+# They cover src/arrow only, which is the part of the node that has no ZED SDK,
+# no CUDA and no dora dependency - so this runs anywhere, and is what CI runs.
+set -euo pipefail
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+REPO_DIR="$(dirname "$SCRIPT_DIR")"
+OUT_DIR="${REPO_DIR}/build/tests"
+
+mkdir -p "$OUT_DIR"
+
+# Sanitized: the release callbacks have to free the whole exported tree, and a
+# leak there would be one per frame.
+g++ -std=c++17 -Wall -Wextra -Werror -g -fsanitize=address,undefined \
+    -I "${REPO_DIR}/src" \
+    -o "${OUT_DIR}/arrow_test" \
+    "${REPO_DIR}/src/arrow/array.cc" "${REPO_DIR}/tests/arrow_test.cc"
+"${OUT_DIR}/arrow_test"
+echo "ok  arrow_test"
+
+# Unsanitized: pyarrow is the consumer standing in for dora, and loads the same
+# code as a shared library.
+g++ -std=c++17 -Wall -Wextra -Werror -O2 -shared -fPIC \
+    -I "${REPO_DIR}/src" \
+    -o "${OUT_DIR}/libzed_arrow.so" \
+    "${REPO_DIR}/src/arrow/array.cc" "${REPO_DIR}/tests/arrow_export.cc"
+uv run --no-project --with pyarrow python "${REPO_DIR}/tests/test_arrow.py"
@@ -0,0 +1,129 @@
+"""Round-trip every exported payload through a real Arrow consumer.
+
+The node builds its Arrow arrays by hand against the C data interface rather
+than linking Arrow C++, so this is what shows that what dora imports on the
+other side of `send_arrow_output` is what went in. It needs neither a camera nor
+the ZED SDK.
+"""
+
+import ctypes
+import pathlib
+import sys
+
+import pyarrow as pa
+
+LIBRARY = pathlib.Path(__file__).resolve().parent.parent / "build" / "tests" / "libzed_arrow.so"
+
+# ArrowArray is ten machine words and ArrowSchema nine, and both want the
+# 8-byte alignment an array of uint64 gives.
+WORDS = 16
+# Index of the `release` field in ArrowArray: a consumer that took ownership
+# zeroes it, which is how this test sees the move happen.
+RELEASE = 8
+
+IMAGE_TYPE = pa.struct([
+    ("width", pa.uint32()),
+    ("height", pa.uint32()),
+    ("encoding", pa.utf8()),
+    ("data", pa.large_binary()),
+])
+
+
+def load():
+    """Load the test library and declare the argument types of its exports."""
+    library = ctypes.CDLL(str(LIBRARY))
+
+    library.zed_export_image.argtypes = [
+        ctypes.c_void_p, ctypes.c_void_p, ctypes.c_uint32, ctypes.c_uint32,
+        ctypes.c_char_p, ctypes.c_char_p, ctypes.c_size_t,
+    ]
+    library.zed_export_float32.argtypes = [
+        ctypes.c_void_p, ctypes.c_void_p, ctypes.POINTER(ctypes.c_float), ctypes.c_size_t,
+    ]
+    library.zed_export_string.argtypes = [
+        ctypes.c_void_p, ctypes.c_void_p, ctypes.c_char_p, ctypes.c_size_t,
+    ]
+    return library
+
+
+def structs():
+    """Allocate the ArrowArray and ArrowSchema the producer fills in."""
+    return (ctypes.c_uint64 * WORDS)(), (ctypes.c_uint64 * WORDS)()
+
+
+def imported(array, schema):
+    """Import the pair as pyarrow does, taking ownership of both."""
+    result = pa.Array._import_from_c(ctypes.addressof(array), ctypes.addressof(schema))
+    assert array[RELEASE] == 0, "the consumer should have taken ownership of the array"
+    return result
+
+
+def test_image(library):
+    """An image row carries its own dimensions, encoding and bytes."""
+    array, schema = structs()
+    pixels = bytes(range(12))
+
+    library.zed_export_image(
+        ctypes.byref(array), ctypes.byref(schema), 2, 2, b"bgr8", pixels, len(pixels)
+    )
+    result = imported(array, schema)
+
+    assert result.type == IMAGE_TYPE, result.type
+    assert result.to_pylist() == [
+        {"width": 2, "height": 2, "encoding": "bgr8", "data": pixels}
+    ]
+
+
+def test_depth(library):
+    """A depth map is an image whose bytes are float32 millimetres."""
+    array, schema = structs()
+    millimetres = [1500.0, 0.0, 250.5, 4000.0]
+    payload = pa.array(millimetres, type=pa.float32()).buffers()[1].to_pybytes()
+
+    library.zed_export_image(
+        ctypes.byref(array), ctypes.byref(schema), 2, 2, b"32FC1", payload, len(payload)
+    )
+    row = imported(array, schema).to_pylist()[0]
+
+    assert row["encoding"] == "32FC1"
+    assert pa.Array.from_buffers(
+        pa.float32(), 4, [None, pa.py_buffer(row["data"])]
+    ).to_pylist() == millimetres
+
+
+def test_float32(library):
+    """Intrinsics and the point cloud go out as plain float32 values."""
+    array, schema = structs()
+    values = (ctypes.c_float * 4)(700.5, 700.5, 640.0, 360.0)
+
+    library.zed_export_float32(ctypes.byref(array), ctypes.byref(schema), values, 4)
+    result = imported(array, schema)
+
+    assert result.type == pa.float32()
+    assert result.to_pylist() == [700.5, 700.5, 640.0, 360.0]
+
+
+def test_string(library):
+    """The camera state goes out as one UTF-8 string."""
+    array, schema = structs()
+
+    library.zed_export_string(ctypes.byref(array), ctypes.byref(schema), b"streaming", 9)
+    result = imported(array, schema)
+
+    assert result.type == pa.utf8()
+    assert result.to_pylist() == ["streaming"]
+
+
+def main():
+    """Run every test, reporting the first failure."""
+    library = load()
+
+    for test in (test_image, test_depth, test_float32, test_string):
+        test(library)
+        print(f"ok  {test.__name__}")
+
+    return 0
+
+
+if __name__ == "__main__":
+    sys.exit(main())
Author	SHA1	Message	Date
cristhian	a4cd493330	docs: shorten the README and correct how the tick is described validate / validate (push) Successful in 58m47s Details validate / test (push) Successful in 58m52s Details validate / test (pull_request) Successful in 58m49s Details validate / validate (pull_request) Successful in 58m48s Details The README carried explanations that belong in AGENTS.md; it now follows the shape of the sibling node repositories and is a quarter shorter. The tick description was also wrong: it does not trigger a grab. Capture is free-running at ZED_FPS and a tick forwards the newest frame there is, so the tick sets the publish rate, and frames captured between two ticks are dropped. The usage snippet listed four of the five outputs, which read as an omission rather than the choice it is.	2026-09-15 10:52:12 -05:00
cristhian	c1a7d70ba6	add typed Arrow payloads and a dora-image-view dataflow dora-image-view takes std/media/v1/Image, and dora's compatibility graph has no edge from std/core/v1/UInt8 to it, so wiring the two failed `dora validate` whatever the node actually sent. Its flat-buffer fallback would not have decoded these frames either: it reads width/height metadata, and this node only published shape. image and depth now go out as the Image struct, camera_info and point_cloud as Float32 arrays and camera_state as a string, all built against the Arrow C data interface in src/arrow so the node still links no Arrow C++. Shape, dtype and encoding metadata are dropped where the payload describes itself; intrinsics, frame_id and both timestamps are unchanged. tests/run.sh covers the packing without a camera or the SDK, round-tripping each array through pyarrow and rebuilding it under the sanitizers. Breaking: image_bgr is renamed to image and every payload changes shape. dataflow_plot.yml is replaced by dataflow_view.yml, which wires the viewer from a tag and repeats its contract in input_types so validate checks both sides of the wiring.	2026-09-15 10:52:08 -05:00
cristhian	d4c9f153c1	Merge pull request 'Split the opencv-plot viewer into its own dataflow' (#19 ) from split-plot-dataflow into main validate / validate (push) Successful in 58m59s Details Reviewed-on: #19	2026-09-08 17:23:12 +00:00
cesarandClaude Opus 5	483da05a98	refactor: split the opencv-plot viewer into its own dataflow validate / validate (push) Successful in 59m2s Details validate / validate (pull_request) Successful in 59m0s Details dataflow.yml is now the camera alone, so running it no longer pulls dora-hub over pip or needs a display. dataflow_plot.yml adds the viewer on image_bgr for when the stream should be looked at. dora 1.0 resolves an input's source only within the same descriptor, so the camera node is declared in both files rather than shared, and the two are run one at a time. CI validates both, which is what catches an output rename that breaks only the viewer. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01A65jaxrPXMN9EhBDMmMWb2	2026-09-08 14:11:25 -03:00
cristhian	86b7a1a8f7	Merge pull request '#18 : v0.2.0 pure camera source on dora 1.0' (#18 ) from v0.2.0-camera-source into main validate / validate (push) Successful in 59m0s Details	2026-09-08 15:06:21 +00:00
cesarandClaude Opus 5	5822a870bb	fix the camera blocking the dora event loop by moving it to its own thread validate / validate (push) Successful in 59m1s Details validate / validate (pull_request) Successful in 59m2s Details Hardware testing showed the tick-driven recovery state machine did not work. async_grab_camera_recovery does not make grab() prompt on a disconnected ZED-M under SDK 5.3: grabs took ~3 s each while the link was down and then blocked indefinitely. The event loop stopped turning, so Stop went unanswered, the 30 s patience timer and the backoff were never reached, and replugging the camera did nothing. Measured: 122 s frozen, then dora stop needed 10 s and a forced kill. Move everything that can block onto a capture thread. zed::Capture owns the camera and runs open, warmup, grab, blank and stall detection, backoff and escalation; it packs each frame into owned buffers and hands the newest one to the reader by swapping under a mutex. The dora event loop now only drains that buffer and publishes, so it never calls into the SDK and stays responsive however long the SDK blocks. The newest frame wins and uncollected frames are dropped, which is what a consumer wants from a camera source. Swapping rather than assigning returns the previous frame's buffers to the capture thread, so steady state does not reallocate. The point cloud is now copied out of the SDK buffer rather than published in place, since the reader is another thread. On exit the loop waits 2 s for the thread and then _Exit()s if it is still inside the SDK, so Stop is always answered promptly. This also removes the blocking warmup from the event loop: it stays a blocking burst, which is harmless on the capture thread. Verified on a ZED-M: unplug leaves the node responsive and logs the backoff 1, 2, 5 then 10 s; replug gives "camera recovered after 13 attempt(s)" and publishing resumes without restarting the dataflow; dora stop with the camera unplugged returns in 0.70 s with the thread joining gracefully. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01Y7g2cBJ5e3r15ZbJ9WZn8c	2026-09-08 12:04:35 -03:00
cesarandClaude Opus 5	2f55ca3f74	docs: correct the output summaries and drop a duplicated paragraph validate / validate (push) Successful in 59m1s Details validate / validate (pull_request) Successful in 59m1s Details The README and AGENTS intros still described the v0.1.0 output set. Also removes a copy of the point-cloud rationale that ended up orphaned after the recovery section landed above it, and narrows the timestamp section to the frame outputs, since camera_state carries only the host clock. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01Y7g2cBJ5e3r15ZbJ9WZn8c	2026-09-08 09:35:09 -03:00
cesarandClaude Opus 5	ee48948de9	add a dora-node.yml manifest and a dora validate CI gate No source package is shared between node repositories, so the manifest and its type URNs are the only contract a consumer has. Declaring them makes a wiring mistake fail at validate time with the producer and consumer URNs, instead of at runtime. Every payload this node sends is a raw buffer whose shape and dtype live in the metadata rather than an Arrow struct, so the URNs name the element type: UInt8 for image_bgr, Float32 for depth, camera_info and point_cloud, String for camera_state. tick is UInt64, matching how dora types timer inputs. dataflow.yml now builds the node from the checkout with path: + build:. A git:-sourced node does not pick up an adjacent manifest, so validating the previous form checked nothing; with path: the CLI reports "injected 6 contract type(s)" and a deliberately mismatched annotation exits non-zero under strict_types. The README keeps the tag: form for consumers. The workflow needs no camera and no ZED SDK, since validation never runs the node. Also ignores the git/ and out/ working directories dora build creates, and drops the ignore rules for the deleted test assets. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01Y7g2cBJ5e3r15ZbJ9WZn8c	2026-09-08 09:34:12 -03:00
cesarandClaude Opus 5	d8956f269d	fix camera recovery blocking the dora event loop Camera::open() retried forever inside a fixed sleep, so a camera that did not come back left the node stuck there: it stopped reading dora events and no longer honoured Stop or AllInputsClosed. Recovery is now a state machine over ticks. open() makes one attempt and returns; the loop decides when to try again from a 1/2/5/10 s backoff deadline, and nothing sleeps, so events keep being read while the camera is down. The first attempt closes the handle; past that the device is wedged and the node escalates to sl::Camera::reboot(), guarded to the ZED 2 and newer since it does nothing on the ZED and ZED Mini. Reopening pins the serial so recovery gets the same physical camera back. Set async_grab_camera_recovery so a link hiccup returns CAMERA_REBOOTING immediately instead of blocking the grab for ~17 s, and enable_image_validity_ check so the SDK flags frames a stalled camera hands back looking valid. Those transient errors no longer drop the handle, since the SDK is already reconnecting it. An all-black frame now counts as a failed grab rather than being published, and a camera delivering nothing usable for 5 s (30 s while the SDK reports it is reconnecting) triggers recovery. A new camera_state output publishes opening/streaming/recovering so a downstream node can tell "no frame yet" from "camera lost". ZED_RETRY_INTERVAL_SECONDS is replaced by the backoff. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01Y7g2cBJ5e3r15ZbJ9WZn8c	2026-09-08 09:26:17 -03:00
cesarandClaude Opus 5	42c2b791fd	make point_cloud optional and publish camera_info once per session ZED_POINT_CLOUD, off by default, gates both retrieveMeasure(XYZRGBA) and the point_cloud output; when off the measure is not retrieved at all. At 1080p a full cloud is ~14.7 MB per frame and costs capture time whether or not anything consumes it, and consumers that need 3D can back-project depth instead. camera_info now goes out once per camera session rather than on every frame: fx, fy, cx, cy and the distortion coefficients are fixed for a given camera and resolution, so repeating them per frame adds no information. It rides the first frame after the camera opens, and again after a reconnection, so it still carries that frame's timestamps. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01Y7g2cBJ5e3r15ZbJ9WZn8c	2026-09-08 09:21:11 -03:00
cesarandClaude Opus 5	617b8ceb50	add depth configuration parity with the reference driver parse_depth_mode returned NEURAL for any unrecognised string, so a typo silently changed depth quality, and NEURAL_PLUS and NEURAL_LIGHT could not be selected at all. All six modes are now reachable and an unknown name exits non-zero listing the accepted values. Parsing moves into Config::from_env() and main reads the configuration before init_dora_node(), so a bad value fails with its own message instead of after the node has registered with the dataflow. Add ZED_CONFIDENCE_THRESHOLD (60) and ZED_TEXTURE_CONFIDENCE_THRESHOLD (100), which were never set, and change the defaults to 1080 / 200 mm / 600 mm to match the reference driver perception was tuned against. The resolved settings are logged at startup. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01Y7g2cBJ5e3r15ZbJ9WZn8c	2026-09-08 09:20:01 -03:00
cesarandClaude Opus 5	15134dc12e	add a depth output Publish sl::MEASURE::DEPTH as float32 [H, W] millimetres on every frame that carries image_bgr, with the intrinsics, frame_id and timestamps the other outputs carry. The map is copied out rather than published in place: sl::Mat rows can be padded, so the buffer is not necessarily H * W floats. inf and nan are cleared to 0 in the same pass, matching the reference driver — a hole is meaningful and a consumer cannot back-project a non-finite value. Consumers that need 3D can now back-project depth with the published intrinsics instead of receiving a point cloud. Also drops the stale objects entry from the dataflow outputs, missed when detection was removed. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01Y7g2cBJ5e3r15ZbJ9WZn8c	2026-09-08 09:17:36 -03:00
cesarandClaude Opus 5	dc7f9f5501	fix frame timestamps to use a comparable epoch steady_clock's epoch is unspecified and typically counts from process start or boot, so the published timestamp_ns could not be compared against another node's timestamps, wall clock or a recording — and it recorded when the node processed the frame rather than when the camera captured it. Publish two keys on every output instead: device_timestamp_ns from sl::Camera::getTimestamp(TIME_REFERENCE::IMAGE), and host_timestamp_ns from system_clock. Both are Unix-epoch nanoseconds, set as dora timestamp parameters. The SDK clock source is pinned to SYSTEM_CLOCK at construction, since it is process-wide and decides the epoch of the device value. Both are kept because the wall clock can step when NTP synchronises after boot on a Jetson, while the device timestamp is what two nodes reading the same frame can agree on. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01Y7g2cBJ5e3r15ZbJ9WZn8c	2026-09-08 09:15:47 -03:00
cesarandClaude Opus 5	126dbf4f32	remove detection from the node dora-zed publishes camera data only. The two engines under src/engines/, the objects output, the ZED_ENGINE/ZED_DETECTION_/ZED_ONNX_ variables and the ZED_PC_MODE=ROI crop are gone, along with the standalone engine test and the model export script. This drops the unconditional ONNX Runtime requirement from CMakeLists, the Dockerfile and the install scripts, so the node now configures on a machine with no ONNX Runtime — which is what blocked the Jetson build, since there is no official ARM64 GPU binary. zed_native is dropped rather than kept: it is bound to the live camera handle and cannot run in a node that receives images over a dataflow. The removed code remains reachable at tag v0.1.0. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01Y7g2cBJ5e3r15ZbJ9WZn8c	2026-09-08 09:12:40 -03:00
cesarandClaude Opus 5	a734692b60	update the build to dora 1.0 and a shell-free build command dora 1.0 runs a node's build command directly rather than through a shell, so the mkdir/cd/&& sequence in dataflow.yml could not work. Move it to scripts/build.sh and invoke that instead. Default CMAKE_BUILD_TYPE to Release so DoraTargets.cmake picks the release cargo profile and the binary does not link debug dora bindings. Pin the dataflow source with tag: — 1.0 replaced git_checkout with the mutually exclusive tag/rev/branch. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01Y7g2cBJ5e3r15ZbJ9WZn8c	2026-09-08 09:10:53 -03:00
cristhian	1dd1cefcc9	Merge pull request 'remove the YOLO-World engine and add a container build to verify it' (#17 ) from remove-yoloworld-engine into main Reviewed-on: #17	2026-09-07 20:07:24 +00:00