Colour Detection, Tracking and Features in Opencv4nodejs

Hey guys, I am doing a robotics project involving opencv4nodejs, but i cannot find any tutorials on how to use colour features. Specifically, I want to capture frames from a camera, and detect red or blue circles/blobs, followed by drawing a circle around them. Any help or guide to tutorials explaining how to do this with opencv4nodejs would be greatly appreciated. Thanks.

No files, tests, or entry points are named in the issue. Start by locating the repository's documentation or examples for camera frames and OpenCV color or blob detection, then define a tutorial covering red and blue detection, tracking, and drawing results; done means the guide is usable by an opencv4nodejs user.

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