frame rate of a QTMovie

gistfile1.m

- (NSTimeInterval)frameRateForMovie:(QTMovie *)movie
{
    for (QTTrack *track in [movie tracks]) {
        QTMedia *media = [track media];
        if (![media hasCharacteristic:QTMediaCharacteristicHasVideoFrameRate])
            continue;
        QTTime duration = [(NSValue *)[media attributeForKey:QTMediaDurationAttribute] QTTimeValue];
        long sampleCount = [(NSNumber *)[media attributeForKey:QTMediaSampleCountAttribute] longValue];
        return sampleCount * ((NSTimeInterval)duration.timeScale / (NSTimeInterval)duration.timeValue);
    }
    return 0.0;
}