读取带有音频的mp4视频文件，编辑帧并将其写入带有音频的新文件

Question

我正在用MATLAB读取一个filename.mp4视频文件。我想编辑图像，但是，我想保持音频完好无损。使用VideoReader和VideoWriter只完成图像部分。我使用了vision.VideoFileReader和'vision.VideoFileWriter‘。我读取了视频和音频文件，然后获取图像并在其旁边添加一张图片。然后写入帧和与其关联的音频。最后的视频显示了我添加的图片，但不是原始图像。感谢您的帮助。

v = VideoReader('movie.mp4');
nfr = v.NumberofFrames;
clear v;
vR = vision.VideoFileReader('movie.mp4','AudioOutputPort',1);
fr = vR.info.VideoFrameRate;
vW = vision.VideoFileWriter('filename.avi','AudioInputPort',1,'FrameRate',fr);

pic = imread('picture.png');%read picture
[a1,b1,~] = size(pic);% get picture size to be resized.


for i = 1:nfr
    [I,audio] = vR();
    I = permute(I,[2,1,3]);%rotate 90 degrees
    if i == 1%resize the picture
        [a,b,~] = size(I);
        pic = imresize(pic,[a,a/a1*b1]);
    end
    I = [I pic];%combine picture and movie frame
    vW(I,audio);%write frame and audio
end
release(vR);
release(vW);

Answer 1

我想通了。

v = VideoReader('movie.mp4');
nfr = v.NumberofFrames;
clear v;
vR = vision.VideoFileReader('movie.mp4','AudioOutputPort',1,'VideoOutDataType','uint8');
%default of VideoOutDataType is 'single', converting it to a similar format is essential
fr = vR.info.VideoFrameRate;
vW = vision.VideoFileWriter('filename.avi','AudioInputPort',1,'FrameRate',fr);

pic = imread('picture.png');%read picture
[a1,b1,~] = size(pic);% get picture size to be resized.


for i = 1:nfr
    [I,audio] = vR();
    I = permute(I,[2,1,3]);%rotate 90 degrees
    if i == 1%resize the picture
        [a,b,~] = size(I);
        pic = imresize(pic,[a,a/a1*b1]);%resizing the pic to same height as movie frame %with proportional width
    end
    I = [I pic];%combine picture and movie frame
    vW(I,audio);%write frame and audio
end
release(vR);
release(vW);