OpenCVMatlab生成视频倒放功能

#include<iOStream>
#include<opencv2/opencv.hpp>

using namespace std;
using namespace cv;

string GetFileNameString(string inputfilename)
{
	string s = "";
	int length = 0;
	while (inputfilename[length] != '\0')
	{
		length++;
	}
	for (length = length - 1; length >= 0; length--)
	{
		if (inputfilename[length] == '\\')
			break;
	}
	while (inputfilename[++length] != '\0')
	{
		if (inputfilename[length] != '.')
			s += inputfilename[length];
		else
			break;
	}
	return s;
}

string GetFolderString(string inputfilename)//Obtain Path in FileNameWithPathString
{
	string s = "";
	int length = 0;
	while (inputfilename[length] != '\0')
	{
		length++;
	}
	for (length = length-1; length >= 0; length--)
	{
		if (inputfilename[length] == '\\')
			break;
	}
	for (int i = 0; i <= length; i++)
		s += inputfilename[i];
	return s;
}

string Replace_folder(string inputfilename) // replace \\ to /
{
	string s = "";
	int length = 0;
	bool flag = true;
	while (inputfilename[length] != '\0')
	{
		if (inputfilename[length] != '\\')
		{
			s += inputfilename[length];
		}
		else
		{
			s += '/';
		}
		length++;
	}
	return s;
}

int main()
{
	string inputVideofilename = "F:\\Users\\VID_20210801_205259.mp4";
	string videopath = GetFolderString(inputVideofilename);
	string picspath = videopath + ("pics_" + GetFileNameString(inputVideofilename));
	string command = "mkdir " + picspath;
	system(command.c_str());//Create the folder which is named pics in current folder
	string picfolder = Replace_folder(picspath) + "/", suffixname = ".jpg";
	cout << "图片和视频保存位置为："+picfolder << endl;
	VideoCapture inputVideo(inputVideofilename);//Obtain input video
	if (!inputVideo.isOpened())
	{
		cout << "Could not open the input video." << inputVideofilename << endl;
		return -1;
	}
	else
	{
		double width = inputVideo.get(CV_CAP_PROP_FRAME_WIDTH);  // width of frame
		double height = inputVideo.get(CV_CAP_PROP_FRAME_HEIGHT); //height of frame
		double frameRate = inputVideo.get(CV_CAP_PROP_FPS);  //frame per second
		double totalFrames = inputVideo.get(CV_CAP_PROP_FRAME_COUNT); //total number of frames

		cout << "视频宽度=" << width << endl;
		cout << "视频高度=" << height << endl;
		cout << "视频总帧数=" << totalFrames << endl;
		cout << "帧率=" << frameRate << endl;

		namedWindow("RGB视频", CV_WINDOW_NORMAL);
		namedWindow("B通道", CV_WINDOW_NORMAL);
		namedWindow("G通道", CV_WINDOW_NORMAL);
		namedWindow("R通道", CV_WINDOW_NORMAL);
		namedWindow("被Canny后的视频", CV_WINDOW_NORMAL);
		Mat lastframe;
		int i = 0;
		while (1)
		{
			Mat frame;// 定义一个Mat变量，用于存储每一帧的图像
			inputVideo >> frame;//读取当前帧
			if (frame.data)
			{
				i++;
				int num_channels = frame.channels();//通道数
				Mat channels[3];
				split(frame, channels);
				Mat zeroRChannel = channels[2].clone();//将R通道全部置0
				zeroRChannel.setTo(0);
				Mat zeroGChannel = channels[1].clone();//将G通道全部置0
				zeroGChannel.setTo(0);
				Mat zeroBChannel = channels[0].clone();//将B通道全部置0
				zeroBChannel.setTo(0);

				Mat BChannels[3] = { channels[0] , zeroGChannel , zeroRChannel };
				Mat mergedBImage;
				merge(BChannels, 3, mergedBImage);

				Mat GChannels[3] = { zeroBChannel , channels[1] , zeroRChannel };
				Mat mergedGImage;
				merge(GChannels, 3, mergedGImage);
				
				Mat RChannels[3] = { zeroBChannel , zeroGChannel , channels[2] };
				Mat mergedRImage;
				merge(RChannels, 3, mergedRImage);

				Mat edges;
				cvtColor(frame, edges, COLOR_BGR2GRAY);
				blur(edges, edges, Size(5, 5));
				Canny(edges, edges, 0, 30, 3);
				imshow("RGB视频", frame);//显示当前帧
				imshow("B通道", mergedBImage);
				imshow("G通道", mergedGImage);
				imshow("R通道", mergedRImage);
				imshow("被Canny后的视频", edges);//显示经过处理后的当前帧
				imwrite(picfolder + to_string(i) + suffixname, frame);
			}
			else
				break;
			waiTKEy(2);
		}
		cout << i << "张图片生成成功，开始逆序合成视频！" << endl;
		Mat frame;
		Mat src0 = imread(picfolder + to_string(i) + suffixname);
		Size size = src0.size();
		VideoWriter writer;
		writer.open(Replace_folder(videopath) + GetFileNameString(inputVideofilename)+"_NiZhuan.avi", CV_FOURCC('M', 'J', 'P', 'G'), frameRate, size, true);
		int j = i;
		for (; j >0; j--)
		{
			string path = picfolder + to_string(j) + suffixname;
			Mat src = imread(path);
			if (!src.empty())
			{
				writer.write(src);
				cout << "正在合成第" << j << "张照片" << endl;
			}
			else
				break;
		}
		if (j == 0)
			std::cout << "合成逆序视频    Successed!" << std::endl;
		else
			std::cout << "合成逆序视频    Failed!" << std::endl;
		return 0;
	}
}

Z = peaks;
surf(Z); 
axis tight manual 
set(gca,'nextplot','replacechildren'); 
v = VideoWriter('peaks.avi');
v.Quality = 95;
v.FrameRate = 40;
open(v);
for k = 1:200 
   surf(sin(2*pi*k/20)*Z,Z)
   frame = getframe(gcf);
   writeVideo(v,frame);
end
close(v);

vidObj = VideoReader('1234.wmv');
vidWidth = vidObj.Width;
vidHeight = vidObj.Height;
vidFps = vidObj.FrameRate;
% 第一种播放方式
while hasFrame(vidObj)
    vidFrame = readFrame(vidObj);
    imshow(vidFrame)
    pause(1/vidObj.FrameRate);
end
% 第二种播放方式
currAxes = axes;
while hasFrame(vidObj)
    vidFrame = readFrame(vidObj);
    image(vidFrame, 'Parent', currAxes);
    currAxes.Visible = 'off';
    pause(1/vidFps);
end
% 第三种播放方式(推荐使用）
mov = struct('cdata',zeros(vidHeight,vidWidth,3,'uint8'),'colormap',[]);
vidObj.CurrentTime = 2.5; % 可设置开始时间
k = 1;
while hasFrame(vidObj)
    mov(k).cdata = readFrame(vidObj);
    imwrite(mov(k).cdata,['pics/', num2str(k),'.jpg']);
    k = k+1;
end
hf = figure;
set(hf,'position',[90 60 vidWidth vidHeight]);
movie(hf,mov,1,vidFps);

filepath = 'D:/Program Files (x86)/MATLAB/myworkspace/';
filename = 'VID_20210801_205259';
suffixname = '.mp4';
vidObj = VideoReader([filepath,filename,suffixname]);
vidWidth = vidObj.Width;
vidHeight = vidObj.Height;
vidFps = vidObj.FrameRate;
% vidObj.CurrentTime = 2.5; % 可设置开始时间
k = 1;
while hasFrame(vidObj)
    frame = readFrame(vidObj);
    imwrite(frame,['pics/', num2str(k),'.jpg']);
    k = k+1;
end

v_all = VideoWriter([filepath,filename,'_NiZhuanMovie_ALL.avi']);
v_all.Quality = 95;
v_all.FrameRate = vidFps;
open(v_all);

v_rgb = VideoWriter([filepath,filename,'_NiZhuanMovie_RGB.avi']);
v_rgb.Quality = 95;
v_rgb.FrameRate = vidFps;
open(v_rgb);

v_r = VideoWriter([filepath,filename,'_NiZhuanMovie_R.avi']);
v_r.Quality = 95;
v_r.FrameRate = vidFps;
open(v_r);
v_g = VideoWriter([filepath,filename,'_NiZhuanMovie_G.avi']);
v_g.Quality = 95;
v_g.FrameRate = vidFps;
open(v_g);

v_b = VideoWriter([filepath,filename,'_NiZhuanMovie_B.avi']);
v_b.Quality = 95;
v_b.FrameRate = vidFps;
open(v_b);

set(gca,'nextplot','replacechildren'); 
for i = k-1:-1:1
    filename = ['D:/Program Files (x86)/MATLAB/myworkspace/pics/', num2str(i),'.jpg'];
    img = imread(filename);
    [m,n]=size(img(:,:,1));
    zero=zeros(m,n);
    rgb_r=img(:,:,1);
    rgb_g=img(:,:,2);
    rgb_b=img(:,:,3);
    R_img=cat(3,rgb_r,zero,zero);
    G_img=cat(3,zero,rgb_g,zero);
    B_img=cat(3,zero,zero,rgb_b);
    RGB_img=cat(3,rgb_r,rgb_g,rgb_b);
    subplot(2,2,1),imshow(R_img),title('红色分量');
    subplot(2,2,2),imshow(G_img),title('绿色分量');
    subplot(2,2,3),imshow(B_img),title('蓝色分量');
    subplot(2,2,4),imshow(RGB_img);
    frame = getframe(gcf);
    imwrite(frame.cdata,['./pics/ALL',num2str(i),'.jpg']);
    imwrite(RGB_img,['./pics/RGB',num2str(i),'.jpg']);
    imwrite(R_img,['./pics/R',num2str(i),'.jpg']);
    imwrite(G_img,['./pics/G',num2str(i),'.jpg']);
    imwrite(B_img,['./pics/B',num2str(i),'.jpg']);
    writeVideo(v_all,frame.cdata);
    writeVideo(v_rgb,RGB_img);
    writeVideo(v_r,R_img);
    writeVideo(v_g,G_img);
    writeVideo(v_b,B_img);
end
close(v_all);
close(v_rgb);
close(v_r);
close(v_g);
close(v_b);