用matlab实现

好的，这里提供一个Matlab实现的基于置乱加密算法的图片加密和解密的代码示例：

% 定义置乱函数
function shuffled_image = shuffle(image)
    % 获取图片的尺寸和通道数
    [height, width, channels] = size(image);

    % 生成随机的置乱矩阵
    indices = randperm(height * width * channels);
    indices = reshape(indices, [height, width, channels]);

    % 根据置乱矩阵对图像进行置乱
    shuffled_image = zeros(size(image));
    for i = 1:height
        for j = 1:width
            for k = 1:channels
                [x, y, z] = find(indices == (i - 1) * width * channels + (j - 1) * channels + k);
                shuffled_image(i, j, k) = image(x, y, z);
            end
        end
    end
end

% 定义解密函数
function image = unshuffle(shuffled_image)
    % 获取图片的尺寸和通道数
    [height, width, channels] = size(shuffled_image);

    % 生成随机的置乱矩阵
    indices = randperm(height * width * channels);
    indices = reshape(indices, [height, width, channels]);

    % 根据置乱矩阵对图像进行还原
    image = zeros(size(shuffled_image));
    for i = 1:height
        for j = 1:width
            for k = 1:channels
                [x, y, z] = find(indices == (i - 1) * width * channels + (j - 1) * channels + k);
                image(x, y, z) = shuffled_image(i, j, k);
            end
        end
    end
end

% 加载原始图像
image_path = 'sample.jpg';
image = imread(image_path);

% 对原始图像进行置乱加密
shuffled_image = shuffle(image);

% 保存加密后的图像
shuffled_image_path = 'shuffled.jpg';
imwrite(shuffled_image, shuffled_image_path);

% 加载加密后的图像
shuffled_image = imread(shuffled_image_path);

% 对加密后的图像进行解密
unshuffled_image = unshuffle(shuffled_image);

% 保存解密后的图像
unshuffled_image_path = 'unshuffled.jpg';
imwrite(unshuffled_image, unshuffled_image_path);

这段代码中，与Python实现类似，首先定义了一个`shuffle()`函数和一个`unshuffle()`函数，分别用于对图像进行置乱加密和解密。

接下来，代码中加载了一个示例图像，并对其进行置乱加密和解密，并将结果保存为加密图像和解密图像。与Python实现不同的是，在Matlab中需要使用`imread()`和`imwrite()`函数来加载和保存图像。