I'm trying to capture frames from a Macbook Pro's iSight using OpenCV 2.4.6, and built using the Apple LLVM 4.2 compiler on Xcode.
However, I don't receive any frames. Usually I set up a while loop to run until the frame is full, but the one below runs for ~30 seconds with no result. How can I debug this?
void testColourCapture() {
cv::VideoCapture capture = cv::VideoCapture(0); //open default camera
if(!capture.isOpened()) {
fprintf( stderr, "ERROR: ColourInput capture is NULL \n" );
}
cv::Mat capFrame;
int frameWaits = 0;
while (capFrame.empty()) {
capture.read(capFrame);
//capture >> capFrame;
cvWaitKey(30);
frameWaits++;
std::cout << "capture >> capFrame " << frameWaits << "\n";
if (frameWaits > 1000) {
break;
}
}
imshow("capFrame", capFrame);
}
I have ensured it is not multi-threaded. Also, capture.isOpened is always returning true.
EDIT: It appears others have had this problem: OpenCV wont' capture from MacBook Pro iSight
EDIT: My procedure for installing opencv was:
$ sudo port selfupdate
$ sudo port install opencv
Then, I dragged libopencv_core.dylib, libopencv_highgui.dylib, libopencv_imgproc.dylib and libopencv_video.dylib into the Frameworks folder of my Xcode project, from /opt/local/lib
OpenCV 2.4.6 is broken and doesn't work with the iSight camera. So install 2.4.5 instead. I've written a step-for-step guide for this: http://accidentalprogramming.blogspot.ch/2013/10/opencv-installation-on-mac-os-x.html
I got it working with following code:
VideoCapture cap = VideoCapture(0); // open the video file for reading
if ( !cap.isOpened() ) // if not success, exit program
{
cout << "Cannot open the video file" << endl;
return -1;
}
//cap.set(CV_CAP_PROP_POS_MSEC, 300); //start the video at 300ms
double fps = cap.get(CV_CAP_PROP_FPS); //get the frames per seconds of the video
cout << "Frame per seconds : " << fps << endl;
namedWindow("MyVideo",CV_WINDOW_AUTOSIZE); //create a window called "MyVideo"
while(1)
{
Mat frame;
bool bSuccess = cap.read(frame); // read a new frame from video
if (!bSuccess) //if not success, break loop
{
cout << "Cannot read the frame from video file" << endl;
break;
}
imshow("MyVideo", frame); //show the frame in "MyVideo" window
if(waitKey(30) == 27) //wait for 'esc' key press for 30 ms. If 'esc' key is pressed, break loop
{
cout << "esc key is pressed by user" << endl;
break;
}
}
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