Cloud Feature Detection

Apparatus and method of detecting clouds, comprising: obtaining images s8 in which each pixel has a respective luminance value; defining intervals for the pixel luminance values; segmenting the image into regions s20 with pixel luminance values in respective ranges; classifying segments s22 with pixel luminance values greater than or equal to a threshold as clouds. Brightness threshold may be determined based on time of day s12 or on camera orientation s14. Atmospheric images may be converted to hue, saturation, luminance (HSL or HSV) format s10. Bands may be between the threshold and maximum luminance. Zone sizes s18 may be based on time of day, camera direction or computational resources. Types of clouds (eg. cumulus, nimbus, cirrus, stratus, altostratus) in a scene including sky may be identified and designated by assigning labels to partitions in each range. Moments may be used to calculate geometric representations of super-pixels that can be used to measure distance between clouds and photographing sensor (s4, Fig. 3). Camera may be mounted on an airplane and detected clouds may be used for autonomous aircraft flight planning, control and navigation (s6, Fig. 3), helping to avoid meteorological weather hazards such as ice, lightning and thunder storms.