请用lab算法写一段matlab在视频中嵌入水印并提取的代码
时间: 2023-06-13 10:06:27 浏览: 114
以下是使用LSB算法在视频中嵌入水印和提取水印的MATLAB代码示例:
```matlab
% 读取视频文件
video = VideoReader('example_video.mp4');
% 读取水印图像
watermark = imread('example_watermark.png');
% 将水印图像转换为二进制序列
watermark_bin = dec2bin(watermark(:), 8) - '0';
watermark_bin = watermark_bin(:);
% 确定每一帧中可用的像素位置
frame_rate = video.FrameRate;
pixel_rate = round(video.Width * video.Height * frame_rate);
pixel_index = randperm(pixel_rate, length(watermark_bin));
% 在每一帧中嵌入水印
for i = 1:video.NumberOfFrames
frame = read(video, i);
% 将帧图像转换为二进制序列
frame_bin = dec2bin(frame(:), 8) - '0';
frame_bin = frame_bin(:);
% 在指定的像素位置嵌入水印
frame_bin(pixel_index) = watermark_bin;
% 将二进制序列转换为帧图像
frame = reshape(frame_bin, [], 8);
frame = bi2de(frame);
frame = reshape(frame, size(frame_bin, 1)/8, []);
frame = uint8(frame);
% 写入帧图像到新的视频文件
writeVideo(new_video, frame);
end
% 提取水印
extracted_watermark_bin = zeros(size(watermark_bin));
for i = 1:video.NumberOfFrames
frame = read(video, i);
% 将帧图像转换为二进制序列
frame_bin = dec2bin(frame(:), 8) - '0';
frame_bin = frame_bin(:);
% 提取已嵌入的水印
extracted_watermark_bin(pixel_index) = frame_bin(pixel_index);
% 如果已提取出完整的水印,则结束循环
if all(extracted_watermark_bin ~= 0)
break;
end
end
% 将提取的二进制序列转换为水印图像
extracted_watermark_bin = reshape(extracted_watermark_bin, [], 8);
extracted_watermark_bin = bi2de(extracted_watermark_bin);
extracted_watermark = reshape(extracted_watermark_bin, size(watermark));
% 显示嵌入的水印和提取的水印
figure;
subplot(1, 2, 1);
imshow(watermark);
title('Original Watermark');
subplot(1, 2, 2);
imshow(extracted_watermark);
title('Extracted Watermark');
```
该代码使用了随机嵌入LSB算法,在每一帧中随机选取像素位置嵌入水印。提取水印时,需要遍历视频中的每一帧,并提取已嵌入的水印。最后,将提取的二进制序列转换为水印图像,并与原始水印进行比较。
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