Measure Image Quality (OpenCV)

How it fits

Typical backends

Caveats

• AccuracyThe blur metric is a heuristic whose useful cutoff varies with camera and lens, so thresholds must be tuned per source rather than carried over as absolute values.
• I/O contractBrightness and contrast are the mean and standard deviation of the grayscale-converted frame, not of the individual colour channels.
• FallbackAn empty in_0 frame produces an all-zero result instead of an error, so a gate keyed on a non-zero score will quietly skip empty frames.
• Parameter interactiondark_threshold and blown_threshold are gray levels in the 0 to 255 range; pixels at or below the former count toward the dark fraction and at or above the latter toward the blown fraction.