Is it possible to crop raw video before extracting all the frames ? [closed]
I want to crop a certain area of my raw video before extract the frames. I don't want to use external cropping video because I need the video to be raw for processing. Is it possible to crop a certain area before frame extraction ? I read about ROI for images, is it possible for video too ?
Here's my extraction code :
#include <opencv2/core/core.hpp>
#include <opencv2/highgui/highgui.hpp>
#include <opencv2/imgproc/imgproc.hpp>
#include <iostream>
#include <string>
#include <sstream>
using namespace cv;
using namespace std;
int c = 0;
string int2str(int &);
int main(int argc, char **argv) {
string s;
VideoCapture cap("test_video.mp4");
if (!cap.isOpened())
{
cout << "Cannot open the video file" << endl;
return -1;
}
double fps = cap.get(CV_CAP_PROP_FPS);
cout << "Frame per seconds : " << fps << endl;
namedWindow("MyVideo", CV_WINDOW_NORMAL);
resizeWindow("MyVideo", 600, 600);
while (1)
{
Mat frame;
Mat Gray_frame;
bool bSuccess = cap.read(frame);
if (!bSuccess)
{
cout << "Cannot read the frame from video file" << endl;
break;
}
s = int2str(c);
//cout<<("%d\n",frame )<<endl;
c++;
imshow("MyVideo", frame);
imwrite("frame" + s + ".jpg", frame);
if (waitKey(30) == 27)
{
cout << "esc key is pressed by user" << endl;
break;
}
}
return 0;
}
string int2str(int &i) {
string s;
stringstream ss(s);
ss << i;
return ss.str();
}
You can read this and then you will find that the answer is no.