# Revision history [back]

Well, I don't believe there's a seek. You need to do it. For example I do it like this :

#include "opencv2/opencv.hpp"
#include "iostream"

using namespace cv;
using namespace std;
int main(int, char**)
{
VideoCapture cap ( "tree.avi" ); // open the default camera
if( ! cap.isOpened () )  // check if we succeeded
return -1;

/* Mat edges; */
namedWindow ( "tree" , 1 );
double frnb ( cap.get ( CV_CAP_PROP_FRAME_COUNT ) );
std::cout << "frame count = " << frnb << endl;

for(;;) {
Mat frame;
double fIdx;

std::cout << "frame index ? ";
std::cin >> fIdx;
if ( fIdx < 0 || fIdx >= frnb ) break;
cap.set ( CV_CAP_PROP_POS_FRAMES , fIdx );
if ( ! success ) {
cout << "Cannot read  frame " << endl;
break;
}
/* cap >> frame; // get a new frame from camera */
imshow("tree", frame);
if ( waitKey (0) == 27 ) break;
}
// the camera will be deinitialized automatically in VideoCapture destructor
return 0;
}


But, there's some errors I can't explain. The execution is OK 'till you start it with an index at most 100 though the FRAME_COUNT says 451 !? For example, let's tell the first frame to read is #100, next you can read any frame indexed before or after 100. I'd like to fix it. I also try the Haris' code but I met the same bug, i.e. the last frame (#450) isn't read... If you could help me to understand I'll be grateful.

Well, I don't believe there's a seek. You need to do it. For example I do it like this :

#include "opencv2/opencv.hpp"
#include "iostream"

using namespace cv;
using namespace std;
int main(int, char**)
{
VideoCapture cap ( "tree.avi" ); // open the default camera
if( ! cap.isOpened () )  // check if we succeeded
return -1;

/* Mat edges; */
namedWindow ( "tree" , 1 );
double frnb ( cap.get ( CV_CAP_PROP_FRAME_COUNT ) );
std::cout << "frame count = " << frnb << endl;

for(;;) {
Mat frame;
double fIdx;

std::cout << "frame index ? ";
std::cin >> fIdx;
if ( fIdx < 0 || fIdx >= frnb ) break;
cap.set ( CV_CAP_PROP_POS_FRAMES , fIdx );
if ( ! success ) {
cout << "Cannot read  frame " << endl;
break;
}
/* cap >> frame; // get a new frame from camera */
imshow("tree", frame);
if ( waitKey (0) == 27 ) break;
}
// the camera will be deinitialized automatically in VideoCapture destructor
return 0;
}


But, there's some errors I can't explain. The execution is OK 'till you start it with an index at most 100 though the FRAME_COUNT says 451 !? For example, let's tell the first frame to read is #100, next you can read any frame indexed before or after 100. I'd like to fix it. I also try the Haris' code but I met the same bug, i.e. the last frame (#450) isn't read... If you could help me to understand I'll be grateful.grateful....

Well, there's no pb ! The test video file was corrupted !!! Thus, you can use the code without trouble.