CMSampleBufferRef memory leak

Question

So I am having a problem with converting some audio. I am getting a huge memory leak when converting and it comes from these lines of code.

dispatch_queue_t mediaInputQueue = dispatch_queue_create("mediaInputQueue", NULL);
[assetWriterInput requestMediaDataWhenReadyOnQueue:mediaInputQueue 
                                        usingBlock: ^ 
 {

     while (assetWriterInput.readyForMoreMediaData) 
     {
         CMSampleBufferRef nextBuffer = [assetReaderOutput copyNextSampleBuffer];
         if (nextBuffer) 
         {

             [assetWriterInput appendSampleBuffer: nextBuffer];
              nextBuffer = NULL;              

         } 
         else 
         {
             // done!
             [assetWriterInput markAsFinished];
             [assetWriter finishWriting];
             [assetReader cancelReading];
             NSDictionary *outputFileAttributes = [[NSFileManager defaultManager]
                                                   attributesOfItemAtPath:exportPath
                                                   error:nil];





             NSNumber *doneFileSize = [NSNumber numberWithLong:[outputFileAttributes fileSize]];
             [self performSelectorOnMainThread:@selector(updateCompletedSizeLabel:)
                                    withObject:doneFileSize
                                 waitUntilDone:NO];

             // release a lot of stuff
             [assetReader release];
             [assetReaderOutput release];
             [assetWriter release];
             [assetWriterInput release];
             [exportPath release];
             break;
         }
     }

 }];

The line that seems to cause the leaks is: CMSampleBufferRef nextBuffer = [assetReaderOutput copyNextSampleBuffer];

I'm lost on this one any help would be greatly appreciated.

ANSWER: Fixed - Just add these lines at the end of the if/else statement.

CMSampleBufferInvalidate(nextBuffer);
         CFRelease(nextBuffer);
         nextBuffer = nil; // NULL?

Answer 1

ANSWER: Fixed - Just add these lines at the end of the if/else statement.

CMSampleBufferInvalidate(nextBuffer);
CFRelease(nextBuffer);
nextBuffer = NULL;