Question

我有一个问题让我在过去几天疯狂。它是关于AVAssetWriterInputPixelBufferAdaptor appendPixelBuffer方法。无论我做什么，它总是在这一行上导致EXC_BAD_ACCESS。我知道有几个帖子在谈论它，但没有人可以帮助我。

这是我的情况：我正在使用OpenGLES渲染到纹理，我想从这些纹理创建一个视频。这是我的代码：

创建FBO，附加纹理和pixelBuffer以填充渲染：

    glGenFramebuffers(1, &_secondFrameBuffer);
glGenRenderbuffers(1, &_depthRenderBuffer);

CVPixelBufferPoolCreatePixelBuffer(NULL, [_videoWriter.pixelBufferInput pixelBufferPool], &_fboTexturePixelBuffer);
CVOpenGLESTextureCacheCreateTextureFromImage(kCFAllocatorDefault,
                                             _textureCache,
                                             _fboTexturePixelBuffer,
                                             NULL,
                                             GL_TEXTURE_2D,
                                             GL_RGBA,
                                             (int)size.width,
                                             (int)size.height,
                                             GL_BGRA,
                                             GL_UNSIGNED_BYTE,
                                             0,
                                             &_fboTexture);

glBindTexture(CVOpenGLESTextureGetTarget(_fboTexture), CVOpenGLESTextureGetName(_fboTexture));
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);


glBindRenderbuffer(GL_RENDERBUFFER, _depthRenderBuffer);
glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH_COMPONENT16, size.width, size.height);

glBindFramebuffer(GL_FRAMEBUFFER, _secondFrameBuffer);

glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, CVOpenGLESTextureGetName(_fboTexture), 0);
glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, _depthRenderBuffer);

glBindFramebuffer(GL_FRAMEBUFFER, _secondFrameBuffer);

AVAssetWriter创建：

    _dataQueue = dispatch_queue_create("data_queue", NULL);
    _assetWriter = [[AVAssetWriter alloc] initWithURL:outputURL fileType:AVFileTypeQuickTimeMovie error:nil];

    int width = [UIScreen mainScreen].applicationFrame.size.width * [UIScreen mainScreen].scale;
    int height = [UIScreen mainScreen].applicationFrame.size.height * [UIScreen mainScreen].scale;

    NSDictionary *videoSettings = [NSDictionary dictionaryWithObjectsAndKeys:
                                   AVVideoCodecH264, AVVideoCodecKey,
                                   [NSNumber numberWithInt:width], AVVideoWidthKey,
                                   [NSNumber numberWithInt:height], AVVideoHeightKey,
                                   nil];

    _assetWriterInput = [AVAssetWriterInput assetWriterInputWithMediaType:AVMediaTypeVideo outputSettings:videoSettings];
    _assetWriterInput.expectsMediaDataInRealTime = YES;

    NSDictionary *bufferAttributes = [NSDictionary dictionaryWithObjectsAndKeys:
                                      [NSNumber numberWithInt:kCVPixelFormatType_32BGRA], kCVPixelBufferPixelFormatTypeKey,
                                      [NSNumber numberWithBool:YES], kCVPixelBufferOpenGLESCompatibilityKey,
                                      nil];

    _assetWriterInputPixelBufferAdaptor = [AVAssetWriterInputPixelBufferAdaptor assetWriterInputPixelBufferAdaptorWithAssetWriterInput:_assetWriterInput sourcePixelBufferAttributes:bufferAttributes];


    [_assetWriter addInput:_assetWriterInput];

    _presentationTime = kCMTimeZero;
    [_assetWriter startWriting];
    [_assetWriter startSessionAtSourceTime:_presentationTime];

然后，我只是尝试附加像素缓冲区......

- (void)appendPixelBuffer:(CVPixelBufferRef)pixelBuffer
{
dispatch_async(_dataQueue, ^{

    if (pixelBuffer != NULL) {
        [_assetWriterInputPixelBufferAdaptor appendPixelBuffer:pixelBuffer    withPresentationTime:_presentationTime];
        CMTime frameTime = CMTimeMake(1, 30);
        _presentationTime = CMTimeAdd(_presentationTime, frameTime);

    } else {
        NSLog(@"NULL PixelBuffer !");
    }
});
}

CRASH - ＆gt; EXC_BAD_ACCESS

任何人都可以帮助我吗？？

感谢！

Answer 1

我在方法- (void)appendPixelBuffer:(CVPixelBufferRef)pixelBuffer中看到了您的问题。如果您使用ARC，请确保您的pixelBuffer未在异步队列中发布，以确保请尝试此代码。

- (void)appendPixelBuffer:(CVPixelBufferRef)pixelBuffer
{
   CVPixelBufferRetain(pixelBuffer);
   dispatch_async(_dataQueue, ^{
      if (pixelBuffer != NULL) {
        [_assetWriterInputPixelBufferAdaptor appendPixelBuffer:pixelBuffer    withPresentationTime:_presentationTime];
        CMTime frameTime = CMTimeMake(1, 30);
        _presentationTime = CMTimeAdd(_presentationTime, frameTime);
        CVPixelBufferRelease(pixelBuffer);
      } else {
        NSLog(@"NULL PixelBuffer !");
      }
   });
}

AVAssetWriterInputPixelBufferAdaptor appendPixelBuffer：EXC_BAD_ACCESS

1 个答案: