First commit

dora_image_viewer/README.md

@@ -0,0 +1,95 @@
+# Dora Node for plotting data with OpenCV
+
+This node is used to plot a text and a list of bbox on a base image (ideal for object detection).
+
+# YAML
+
+```yaml
+- id: dora-image-viewer
+  build: pip install ../../dora_image_viewer
+  path: dora_image_viewer/dora_image_viewer/main.py
+  inputs:
+    # image: Arrow array of size 1 containing the base image
+    # bbox: Arrow array of bbox
+    # text: Arrow array of size 1 containing the text to be plotted
+
+  env:
+    PLOT_WIDTH: 640 # optional, default is image input width
+    PLOT_HEIGHT: 480 # optional, default is image input height
+```
+
+# Inputs
+
+- `image`: Arrow array containing the base image
+
+```python
+## Image data
+image_data: UInt8Array # Example: pa.array(img.ravel())
+metadata = {
+  "width": 640,
+  "height": 480,
+  "shape": [480, 640, 3], # optional alternative to width/height
+  "encoding": str, # bgr8, rgb8
+}
+
+## Example
+node.send_output(
+  image_data, {"width": 640, "height": 480, "encoding": "bgr8"}
+  )
+
+## Decoding
+storage = event["value"]
+
+metadata = event["metadata"]
+encoding = metadata["encoding"]
+width = metadata.get("width")
+height = metadata.get("height")
+shape = metadata.get("shape")
+
+if encoding == "bgr8":
+    channels = 3
+    storage_type = np.uint8
+
+frame = (
+    storage.to_numpy()
+    .astype(storage_type)
+    .reshape((height, width, channels))
+)
+```
+
+- `bbox`: an arrow array containing the bounding boxes, confidence scores, and class names of the detected objects
+
+```Python
+
+bbox: {
+    "bbox": np.array,  # flattened array of bounding boxes
+    "conf": np.array,  # flat array of confidence scores
+    "labels": np.array,  # flat array of class names
+}
+
+encoded_bbox = pa.array([bbox], {"format": "xyxy"})
+
+decoded_bbox = {
+    "bbox": encoded_bbox[0]["bbox"].values.to_numpy().reshape(-1, 4),
+    "conf": encoded_bbox[0]["conf"].values.to_numpy(),
+    "labels": encoded_bbox[0]["labels"].values.to_numpy(zero_copy_only=False),
+}
+```
+
+- `text`: Arrow array containing the text to be plotted
+
+```python
+text: str
+
+encoded_text = pa.array([text])
+
+decoded_text = encoded_text[0].as_py()
+```
+
+## Example
+
+Check example at [examples/python-dataflow](examples/python-dataflow)
+
+## License
+
+This project is licensed under Apache-2.0. Check out [NOTICE.md](../../NOTICE.md) for more information.