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For iOS 13 beta.I'm using AVAssetWriter writing CMSampleBuffer from CGImage to mp4 file, but occasinally this error occurs:Error Domain=AVFoundationErrorDomain Code=-11800 "The operation could not be completed" UserInfo={NSLocalizedFailureReason=An unknown error occurred (-16345), NSLocalizedDescription=The operation could not be completed, NSUnderlyingError=0x28189d470 {Error Domain=NSOSStatusErrorDomain Code=-16345 "(null)"}}what does code = -16345 mean? where can I get those errors' description documents?With great appreciate for your help.