ios - AVAssetWriterInputPixelBufferAdaptor 内存管理

Question

我正在使用 AVAssetWriterInputPixelBufferAdaptor 将一些帧写入视频，当我写入大量帧时，我的应用程序由于内存分配而崩溃。我怎样才能防止这种情况？这是代码：

AVAssetWriterInput *writerInput = [AVAssetWriterInput assetWriterInputWithMediaType:AVMediaTypeVideo outputSettings:videoSettings];  

NSDictionary *sourcePixelBufferAttributesDictionary = [NSDictionary dictionaryWithObjectsAndKeys:
                                                       [NSNumber numberWithInt:kCVPixelFormatType_32ARGB], kCVPixelBufferPixelFormatTypeKey, nil];

 AVAssetWriterInputPixelBufferAdaptor *adaptor = [AVAssetWriterInputPixelBufferAdaptor           
 assetWriterInputPixelBufferAdaptorWithAssetWriterInput:writerInput  
 sourcePixelBufferAttributes:sourcePixelBufferAttributesDictionary]; 


CVPixelBufferRef buffer = NULL;
                buffer = (CVPixelBufferRef)[self pixelBufferFromCGImage:[tmpImg CGImage] size:size];
                if (buffer)
                {
                    if(![adaptor appendPixelBuffer:buffer withPresentationTime:presentTime])
                        NSLog(@"FAIL");
                    else
                        NSLog(@"Success:%d",i);
                        CFRelease(buffer);

                }

使用 Xcode Instruments 时，泄漏似乎发生在

if(![adaptor appendPixelBuffer:buffer withPresentationTime:presentTime])

（ AVAssetWriterInputPixelBufferAdaptor ）

真的可以使用一些帮助或指向一个工作示例的指针。谢谢！