The following table contains the requirements for cameras used by the Queue detection tool:
Camera: | - resolution: 360 х 288 (CIF1) to 720 х 576 (CIF4) pixels; lager images are scaled down to CIF4;
- frames per second: 6 or more;
- color: color or greyscale;
- no camera jitter is allowed.
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Illumination: | - best recognition results are achieved under moderate illumination. If the scene is under- or over-illuminated, the recognition accuracy may drop down;
- sharp changes in illumination may lead to improper operation of analytics.
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Scene and viewing angle: | - vertically downward position is the best for the purpose. The closer to vertical, the more accurate counting;
- camera FOV dimensions: min. 3 x 3m (6 x 6 humans), optimal 4 x 4m (8 x 8x humans), max. 8 x 8m (16 x 16 humans);
- the background must be primarily static and not undergo sudden changes;
- reflective surfaces and harsh shadows from moving objects can affect the quality of analytics;
- leafage, TV screens or any periodic object movement in the background may cause analytics glitches.
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Images of objects within the scene: | - image quality: the image must be clear and sharp with no visible compression artifacts;
- dimensions of a human in scene: bounding rectangle has to occupy 0.25 to 10 percent of the frame area.
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