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我想使用该方法将 a 转换CGImageCMSampleBufferRef并将其附加到 a 。我已经设法使用以下代码获得了,但是当我提供结果时简单地返回. 我究竟做错了什么?AVAssetWriterInputappendSampleBuffer:CMSampleBufferRefappendSampleBuffer:NOCMSampleBufferRef

- (void) appendCGImage: (CGImageRef) frame
{
    const int width = CGImageGetWidth(frame);
    const int height = CGImageGetHeight(frame);

    // Create a dummy pixel buffer to try the encoding
    // on something simple.
    CVPixelBufferRef pixelBuffer = NULL;
    CVReturn status = CVPixelBufferCreate(kCFAllocatorDefault, width, height,
        kCVPixelFormatType_32BGRA, NULL, &pixelBuffer);
    NSParameterAssert(status == kCVReturnSuccess && pixelBuffer != NULL);

    // Sample timing info.
    CMTime frameTime = CMTimeMake(1, 30);
    CMTime currentTime = CMTimeAdd(lastSampleTime, frameTime);
    CMSampleTimingInfo timing = {frameTime, currentTime, kCMTimeInvalid};

    OSStatus result = 0;

    // Sample format.
    CMVideoFormatDescriptionRef videoInfo = NULL;
    result = CMVideoFormatDescriptionCreateForImageBuffer(NULL,
         pixelBuffer, &videoInfo);
    NSParameterAssert(result == 0 && videoInfo != NULL);

    // Create sample buffer.
    CMSampleBufferRef sampleBuffer = NULL;
    result = CMSampleBufferCreateForImageBuffer(kCFAllocatorDefault,
        pixelBuffer, true, NULL, NULL, videoInfo, &timing, &sampleBuffer);
    NSParameterAssert(result == 0 && sampleBuffer != NULL);

    // Ship out the frame.
    NSParameterAssert(CMSampleBufferDataIsReady(sampleBuffer));
    NSParameterAssert([writerInput isReadyForMoreMediaData]);
    BOOL success = [writerInput appendSampleBuffer:frame];
    NSParameterAssert(success); // no go :(
}

PS 我知道这段代码中存在内存泄漏,为了简单起见,我省略了一些代码。

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1 回答 1

6

啊哈,我完全错过AVAssetWriterInputPixelBufferAdaptor了专门用于将像素缓冲区管道传输到写入器输入的类。现在代码可以工作了,即使没有乱七八糟的CMSampleBuffer东西。

于 2010-09-21T07:30:16.627 回答