Abstract: In allusion to common deficiency of existing scrambling algorithm,an image scrambling algorithm based on SOMA CUBE square matching was proposed．To scramble an image,bit-plane of the original image is firstly exchanged to change the pixel grayscale,and then this image is divided into blocks according to SOMA CUBE；finally,any two matching methods of SOMA CUBE are chosen,and one is seen as the matching way of original image elements,the otheris the scrambling image,and puting the twos conversion,so as to realize the image scrambling．The scrambling image shows the white noise is not the problem of cyclical recovery safety,scrambling is relatively stable,can quickly achieve ideal scrambling effect,and there are not requirements for image size．The experimental results show that this algorithm can effectively achieve the gray image scrambling,has a good visual effect and quantitative evaluation results,and can resist certain geometrical attack．

Key words: Image scrambling,SOMA CUBE,Plane exchange,Scrambling degree