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CV_CAP_PROP_POS_FRAMES not working w/iOS

I developed a project where I am supposed to read frames from a video file. In my case, a .mov file straight from an iPhone capture.

This application is supposed to work on both Mac OS X and iPhone.

Unfortunately, seeking into the file does not work with iOS although it works with Mac OS (each build is linked to its proper OpenCV framework).

In the following code, setting frame always starts file from the begining, and get always returns 1, although frames are actually seeked properly as I displayed them.

Maybe it is just that iOs OpenCV framework is not at the same features levels as the Mac OS one ?

VideoCapture *videoCapture = nil;
videoCapture = new VideoCapture(filePath);
videoCapture->set(CV_CAP_PROP_POS_FRAMES, numframe);

...
loop
    videoCapture->read(grabbedFrame);
    int numframe = videoCapture->get(CV_CAP_PROP_POS_FRAMES);

....

Notes :

  • Currently my target is iOS simulator. Did not checked yet w/ real iPhone

  • I have the same behaviour for MSEC and FRAMES modes.

CV_CAP_PROP_POS_FRAMES not working w/iOS

I developed a project where I am supposed to read frames from a video file. In my case, a .mov file straight from an iPhone capture.

This application is supposed to work on both Mac OS X and iPhone.

Unfortunately, seeking into the file does not work with iOS although it works with Mac OS (each build is linked to its proper OpenCV framework).

In the following code, setting frame always starts file from the begining, and get always returns 1, although frames are actually seeked properly as I displayed them.

Maybe it is just that iOs OpenCV framework is not at the same features levels as the Mac OS one ?

VideoCapture *videoCapture = nil;
videoCapture = new VideoCapture(filePath);
videoCapture->set(CV_CAP_PROP_POS_FRAMES, numframe);

...
loop
    videoCapture->read(grabbedFrame);
    int numframe = videoCapture->get(CV_CAP_PROP_POS_FRAMES);

....

Notes :

  • Currently my target is iOS simulator. Did not checked yet w/ real iPhone

  • I have the same behaviour for MSEC and FRAMES modes.