关键代码
- (void)updateFps:(NSInteger) fps{
NSArray *videoDevices = [AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo];
for (AVCaptureDevice *vDevice in videoDevices) {
float maxRate = [(AVFrameRateRange *)[vDevice.activeFormat.videoSupportedFrameRateRanges objectAtIndex:0] maxFrameRate];
if (maxRate >= fps) {
if ([vDevice lockForConfiguration:NULL]) {
vDevice.activeVideoMinFrameDuration = CMTimeMake(10, (int)(fps * 10));
vDevice.activeVideoMaxFrameDuration = vDevice.activeVideoMinFrameDuration;
[vDevice unlockForConfiguration];
}
}
}
}
