Abstract: The presented cloud model algorithm is used to improve the quality of denoised image.
Firstly, the normal cloud generator is used to produce cloud droplet. Secondly, the positive cloud droplet
is mapped to the pixels that grayscale is bigger than the average grayscale of image, the negative cloud
droplet is mapped to the pixels that grayscale is smaller than the average grayscale of image, and
different code is represented by gray feature of different pixel. Thirdly, the rule of code is divided into
flat and non flat blocks, and the flat block area is maintained quality level. Finally, the processing of
image mosaic is described. The experiment results show that this mechanism is efficient and can find
the global optimal solution with high probability.

Key words: cloud droplet, code, gray scale