基于catmap的置乱算法

*只能计算正方形图片
测试图片为200*200*3
*示例图片

*code

function test    clcclearclose all;pic = imread('1.jpg');sub_h = 3;sub_w = 3;subplot(sub_h,sub_w,1);imshow(pic);title('原图');pic_size = size(pic)assert(pic_size(1) == pic_size(2),'二位数组长度必须相等');%pic_r = pic(:,:,1);%pic_g = pic(:,:,1);%pic_b = pic(:,:,1);a = [5,2,3;4,5,8;1,2,4;8,5,3];b = [3,1,2;7,6,1;5,6,2;2,4,7];%a(次数，通道数)count = 3;%次数piccat(pic_size(1),pic_size(2),pic_size(3)) = 0;picdecat(pic_size(1),pic_size(2),pic_size(3)) = 0;pic_src = pic;for t = 1:count    for c = 1:pic_size(3)    %for c = 1:1        for x = 1 : pic_size(1)            for y = 1:pic_size(2)                catpos = [x,y] * [1 a(t,c);b(t,c) a(t,c)*b(t,c)+1];                cat_x = catpos(1);                cat_y = catpos(2);                while(cat_x > pic_size(1))                    cat_x = cat_x - pic_size(1);                end                while(cat_y > pic_size(2))                    cat_y = cat_y - pic_size(2);                end                piccat(cat_x,cat_y,c) = pic_src(x,y,c);                %[t,x,y,c,cat_x,cat_y,pic(x,y,c)]            end        end    end    pic_src = uint8(piccat);    subplot(sub_h,sub_w,t+sub_w);    imshow(uint8(pic_src),[]);    title(sprintf('加密%d次' ,t));endsubplot(sub_h,sub_w,2);imshow(uint8(piccat),[]);title('加密图');pic_src = piccat;for t = 1:count    for c = 1:pic_size(3)    %for c = 1:1        for x = 1 : pic_size(1)            for y = 1:pic_size(2)                catpos = [x,y] * [1 a(count - t + 1,c);b(count - t + 1,c) a(count - t + 1,c)*b(count - t + 1,c)+1];                cat_x = catpos(1);                cat_y = catpos(2);                while(cat_x > pic_size(1))                    cat_x = cat_x - pic_size(1);                end                while(cat_y > pic_size(2))                    cat_y = cat_y - pic_size(2);                end                picdecat(x,y,c) = pic_src(cat_x,cat_y,c);                %[t,x,y,c,cat_x,cat_y,pic(x,y,c)]            end        end    end    pic_src = uint8(picdecat);    subplot(sub_h,sub_w,t+sub_w * 2);    imshow(uint8(pic_src),[]);    title(sprintf('解密%d次' ,t));endsubplot(sub_h,sub_w,3);imshow(uint8(picdecat),[]);title('解密');end