I have a series of satellite images in 4 bands (red, green, blue and NIR). What is the easiest way to estimate what percentage of each image is covered by clouds? The image is less than 1x1 km with 3-5 m resolution.
As far as I understand,
fmask does not work here (it requires more bands), but maybe there is some simple heuristic (preferably one that can be calculated just on a pixel-by-pixel basis)?