In this paper

we introduce the research background and key technical parameters of “Hangtian Tsinghua

1

” micro

s

atellite. The scheme of on

b

oard image intelligent processing

which includes cloud detection and image compression

is discussed in detail. Cloud detection is based on the cloud’s brightness character and we use gray threshold method to achieve image segmentation through the analysis of image histogram. Image compression method is a mend of Block Truncation Coding method that implements three

l

evel compression according to the activity of the image block. All on

b

oard image processing tasks are fulfilled by the Transputer processor. The image processing work on the ground mainly including noise removal and image correction is discussed in the end.