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How far from the camera can the face be tracked/detected?
We define a face as Face in the image is defined by a square encompassing all the facial features also known as the facial bounding box. The tracking distance depends on the camera resolution. For the face to be detected and tracked, the facial bounding box size must be at least 5% of the larger image resolution. For example, for a webcam with resolution 1920×1080 (Logitech C920), the minimal facial bounding box is 96×96 pixels ( 1920 x 0,05 ) which corresponds to faces up to ~5 meters from this specific camera.
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