我正在使用 AVAssetWriter/AVAssetReader 将 PCM 音频文件转码为 AAC。我把它归结为一个在 iOS6 中工作但在 iOS7 中失败的简单项目。
一切都很顺利,直到我到达 [self.assetWriter finishWritingWithCompletionHandler:] 然后assetWriter 进入失败状态,错误设置为-11800 AVFoundation 未知错误,内部错误设置为-12733,这显然对应于SampleBufferNotReady。
dispatch_queue_t queue = dispatch_queue_create("audio.encode", DISPATCH_QUEUE_SERIAL);
success = [self.assetWriter startWriting];
if (!success)
{
[self showStatus:@"Export: writer failed to startWriting"];
return;
}
[self.assetWriter startSessionAtSourceTime:kCMTimeZero];
[assetWriterInput requestMediaDataWhenReadyOnQueue:queue
usingBlock:
^{
while([assetWriterInput isReadyForMoreMediaData])
{
NSAssert (self.assetWriter.status == AVAssetWriterStatusWriting, nil);
CMSampleBufferRef sampleBuffer = [assetReaderOutput copyNextSampleBuffer];
if (sampleBuffer)
{
NSAssert (CMSampleBufferIsValid(sampleBuffer), nil);
NSAssert (CMSampleBufferDataIsReady(sampleBuffer), nil);
BOOL success = [assetWriterInput appendSampleBuffer:sampleBuffer];
if (!success)
{
[self showError:self.assetWriter.error];
self.assetWriter = nil;
CFRelease(sampleBuffer);
return;
}
CFRelease(sampleBuffer);
}
else
{
if ([assetReader status] == AVAssetReaderStatusCompleted)
{
[assetWriterInput markAsFinished];
[self.assetWriter finishWritingWithCompletionHandler:^{
BOOL success = self.assetWriter.status == AVAssetWriterStatusCompleted;
if (success)
{
[self showStatus: @"Did it!"];
self.assetWriter = nil;
}
else
{
[self showError:self.assetWriter.error];
self.assetWriter = nil;
}
}];
}
else
{
[self showError:assetReader.error];
self.assetWriter = nil;
}
}
}
}
];
注意:我在 Apple 发布了一个错误,发布到开发论坛并使用了 TSI。还没有得到任何答案。我希望你们中的一个天才会指出我的解决方法。