I am having an issue running GPUImage. I have modified SimpleVideoFileFilter program(replaced the filter with a chromakeyfilter) and am using my own video. My program is terminating due to the following error: [AVAssetWriter startWriting] Cannot call method when status is 3' I have gone through the forums but not sure why the moviewriter is closing and then someone is writing to it. I am using iPhone4 running iOS 7.0 Any clues are greatly appreciated. Thanks much!