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    <p>It's unclear from your question whether you are talking about video samples or audio samples. To read video samples, you need to do the following:</p> <ol> <li><p>Construct an AVAssetReader:</p> <p><code>asset_reader = [[AVAssetReader alloc] initWithAsset:asset error:&amp;error]; (error checking goes here)</code></p></li> <li><p>Get the video track(s) from your asset:</p> <p><code>NSArray* video_tracks = [asset tracksWithMediaType:AVMediaTypeVideo]; AVAssetTrack* video_track = [video_tracks objectAtIndex:0];</code></p></li> <li><p>Set the desired video frame format:</p> <pre>NSMutableDictionary* dictionary = [[NSMutableDictionary alloc] init]; [dictionary setObject:[NSNumber numberWithInt:&lt;format code from CVPixelBuffer.h&gt;] forKey:(NSString*)kCVPixelBufferPixelFormatTypeKey];</pre> <p>Note that certain video formats just will not work, and if you're doing something real-time, certain video formats perform better than others (BGRA is faster than ARGB, for instance).</p></li> <li><p>Construct the actual track output and add it to the asset reader:</p> <pre>AVAssetReaderTrackOutput* asset_reader_output = [[AVAssetReaderTrackOutput alloc] initWithTrack:video_track outputSettings:dictionary]; [asset_reader addOutput:asset_reader_output];</pre></li> <li><p>Kick off the asset reader:</p> <p><code>[asset_reader startReading];</code></p></li> <li><p>Read off the samples:</p> <pre> CMSampleBufferRef buffer; while ( [asset_reader status]==AVAssetReaderStatusReading ) buffer = [asset_reader_output copyNextSampleBuffer]; </pre></li> </ol>
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    1. COThanks damian. I was actually asking about audio. I can get the audio into the buffer, but don't know how to get at the samples within the buffer.
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      1. USEric Christensen
 

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