create a video from image sequence in open cv - c++

Question

I am working on open cv with c++.I have around 30 frames of images .I need to combine these frames to obtain a video.Can anyone suggest me method?Is it like reading each frames and storing in videowriter?Please suggest

Answer 1

I would suggest using ffmpeg. You can do it programmatically or using the command line. An example of doing this on the command line is:
ffmpeg -start_number n -i image%d.jpg -vcodec mpeg4 test.avi
Where n is the first image number.

Answer 2

Tutorial how to do Videooutput
You will be asked for the codec you want to use. It's a bit complicated, but there are already many codec related questions on SO.
This code should work (not tested):
#include <iostream> // for standard I/O
#include <string> // for strings
#include <vector>
#include <opencv2/core/core.hpp> // Basic OpenCV structures (cv::Mat)
#include <opencv2/highgui/highgui.hpp> // Video write
using namespace std;
using namespace cv;
int main(int argc, char *argv[], char *window_name){
vector<Mat> images; //fill this somehow
Size S = vector[0].getSize();
VideoWriter outputVideo; // Open the output
outputVideo.open(NAME , ex=-1, 30), S, true); //30 for 30 fps
if (!outputVideo.isOpened()){
cout << "Could not open the output video for write: "<< endl;
return -1;
}
for(int i=0; i<images.size(); i++){
outputVideo << res;
}
cout << "Finished writing" << endl;
return 0;
}