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copied!<p>With a little more searching and reading I have a working solution. Don't know that it is best method, but so far, so good.</p> <p>In my setup area I've setup an AVAssetWriterInputPixelBufferAdaptor. The code addition looks like this.</p> <pre><code>InputWriterBufferAdaptor = [AVAssetWriterInputPixelBufferAdaptor assetWriterInputPixelBufferAdaptorWithAssetWriterInput: inputWriterBuffer sourcePixelBufferAttributes: nil]; [inputWriterBufferAdaptor retain]; </code></pre> <p>For completeness to understand the code below, I also have these three lines in the setup method.</p> <pre><code>fpsOutput = 30; //Some possible values: 30, 10, 15 24, 25, 30/1.001 or 29.97; cmTimeSecondsDenominatorTimescale = 600 * 100000; //To more precisely handle 29.97. cmTimeNumeratorValue = cmTimeSecondsDenominatorTimescale / fpsOutput; </code></pre> <p>Instead of applying a retiming to a copy of the sample buffer. I now have the following three lines of code that effectively does the same thing. Notice the withPresentationTime parameter for the adapter. By passing my custom value to that, I gain the correct timing I'm seeking.</p> <pre><code>CVPixelBufferRef myImage = CMSampleBufferGetImageBuffer( sampleBuffer ); imageSourceTime = CMTimeMake( writtenFrames * cmTimeNumeratorValue, cmTimeSecondsDenominatorTimescale); appendSuccessFlag = [inputWriterBufferAdaptor appendPixelBuffer: myImage withPresentationTime: imageSourceTime]; </code></pre> <p>Use of the AVAssetWriterInputPixelBufferAdaptor.pixelBufferPool property may have some gains, but I haven't figured that out.</p>

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