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canSetSessionPreset:AVCaptureSessionPreset1920x1080 causes 'Bad Access' in iOS4

Here is my code:

if( [self.captureSession canSetSessionPreset:AVCaptureSessionPreset1920x1080] == YES )
    {
    [self.captureSession setSessionPreset:AVCaptureSessionPreset1920x1080];
    self.currentPreset = GMCVideoCaptureRecordingPresetFullHD;
    }

On iOS4 execution stops on the first line with 'Bad access' error. On iOS5 it works fine.

How to correctly check for compatibility here?

AVCaptureSessionPreset1920x1080 is an NSString *const . You can just check that its address is not NULL . So like so:

if( &AVCaptureSessionPreset1920x1080 != NULL && [self.captureSession canSetSessionPreset:AVCaptureSessionPreset1920x1080] == YES )
{
    [self.captureSession setSessionPreset:AVCaptureSessionPreset1920x1080];
    self.currentPreset = GMCVideoCaptureRecordingPresetFullHD;
}

That should do what you want. Note that you won't be setting the preset on < iOS 5 though so you will presumably want an else in there to handle the case of it being < iOS 5 or the 1920x1080 preset can't be set.

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