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我試圖使用AVAssetWriter，它也接受音頻輸入進行屏幕錄製。不過，我一直停留在這個錯誤，其中AVAssetWriter有時候會後，打了幾個電話上appendSampleBuffer:（內encodeAudioFrame:）AVAssetWriter去appendSampleBuffer後的AVAssetWriterStatusFailed：
Failed: Error Domain=AVFoundationErrorDomain Code=-11800 "The operation could not be completed" UserInfo=0x32b570 {NSLocalizedDescription=The operation could not be completed, NSUnderlyingError=0x70d710 "The operation couldn’t be completed. (OSStatus error -12737.)", NSLocalizedFailureReason=An unknown error occurred (-12737)}
一些觀察AVAssetWriterStatusFailed：
- 一旦進入這種狀態，隨後的記錄嘗試即使我使用不同的記錄器對象，也會返回AVAssetWriterStatusFailed。
- 當我將音頻記錄塊註釋掉時，錯誤不會顯示。
- 但是，當我註釋掉視頻記錄塊並且不修改任何傳入的CMSampleBufferRef時，錯誤依然出現。
任何援助將不勝感激。
下面是我使用的代碼，爲簡潔起見省略了幾個部分。我正在使用OSX 10.9 SDK，並關閉了ARC。
- (BOOL) startRecording
{
if (!isRecording)
{
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
[self startCapture];
[self setUpWriter];
startedAt = [NSDate date];
isRecording = YES;
while (isRecording)
{
NSAutoreleasePool* pool = [NSAutoreleasePool new];
NSTimeInterval offset = [[NSDate date] timeIntervalSinceDate:startedAt];
CMTime tiem = CMTimeMakeWithSeconds(offset - pauseDelta, 1000);
[self encodeFrameAtTime:tiem];
[pool drain];
sleep(0.05f);
}
[self endCapture];
[self completeRecordingSession];
});
}
return YES;
}
- (void) stopRecording {
isRecording = NO;
}
-(void) startCapture
{
AVCaptureDevice* microphone = x //Device selection code omitted
videoCaptureSession = [[AVCaptureSession alloc] init];
videoCaptureSession.sessionPreset = AVCaptureSessionPresetHigh;
//------------------------------------------
NSError* err = nil;
audioInput = [AVCaptureDeviceInput deviceInputWithDevice:microphone error:&err];
[videoCaptureSession addInput:audioInput];
//------------------------------------------
audioOutput = [[AVCaptureAudioDataOutput alloc] init];
queue = dispatch_queue_create("videoQueue", NULL);
[audioOutput setSampleBufferDelegate:self queue:queue];
[videoCaptureSession addOutput:audioOutput];
audioDelta = -1;
[videoCaptureSession startRunning];
}
-(void) endCapture
{
[videoCaptureSession stopRunning];
[videoCaptureSession removeInput:audioInput];
[videoCaptureSession removeOutput:audioOutput];
[audioOutput release];
audioOutput = nil;
audioInput = nil;
[videoCaptureSession release];
videoCaptureSession = nil;
dispatch_release(queue);
}
-(BOOL) setUpWriter
{
//delete the file.
{
NSFileManager* fileManager = [NSFileManager defaultManager];
if ([fileManager fileExistsAtPath:self.moviePath]) {
NSError* error;
if ([fileManager removeItemAtPath:self.moviePath error:&error] == NO) {
NSLog(@"Could not delete old recording file at path: %@", self.moviePath);
}
}
}
mCaptureRect = NSRectToCGRect([screen frame]);
int FWidth = mCaptureRect.size.width;
int FHeight = mCaptureRect.size.height;
int bitRate = FWidth * FHeight * 8;
videoWriter = [[AVAssetWriter alloc] initWithURL:[NSURL fileURLWithPath:self.moviePath] fileType:AVFileTypeMPEG4 error:nil];
NSParameterAssert(videoWriter);
//Configure video
NSDictionary *codecSettings = [NSDictionary dictionaryWithObjectsAndKeys:
[NSNumber numberWithInt:bitRate], AVVideoAverageBitRateKey,
nil];
NSDictionary* videoSettings = [NSDictionary dictionaryWithObjectsAndKeys:
AVVideoCodecH264, AVVideoCodecKey,
codecSettings,AVVideoCompressionPropertiesKey,
[NSNumber numberWithInt:FWidth], AVVideoWidthKey,
[NSNumber numberWithInt:FHeight], AVVideoHeightKey,
nil];
videoWriterInput = [AVAssetWriterInput assetWriterInputWithMediaType:AVMediaTypeVideo outputSettings:videoSettings];
NSParameterAssert(videoWriterInput);
videoWriterInput.expectsMediaDataInRealTime = YES;
NSDictionary* bufferAttributes = [NSDictionary dictionaryWithObjectsAndKeys:
[NSNumber numberWithInt:kCVPixelFormatType_32ARGB], kCVPixelBufferPixelFormatTypeKey,
[NSNumber numberWithInt:FWidth], kCVPixelBufferWidthKey,
[NSNumber numberWithInt:FHeight], kCVPixelBufferHeightKey,
nil];
avAdaptor = [AVAssetWriterInputPixelBufferAdaptor assetWriterInputPixelBufferAdaptorWithAssetWriterInput:videoWriterInput sourcePixelBufferAttributes:bufferAttributes];
//*
//Configure Audio
AudioChannelLayout acl;
bzero(&acl, sizeof(acl));
acl.mChannelLayoutTag = kAudioChannelLayoutTag_Mono;
NSDictionary* audioSettings = [ NSDictionary dictionaryWithObjectsAndKeys:
[ NSNumber numberWithInt: kAudioFormatMPEG4AAC], AVFormatIDKey,
[ NSNumber numberWithFloat: 44100.0 ], AVSampleRateKey,
[ NSNumber numberWithInt: 1 ], AVNumberOfChannelsKey,
[ NSData dataWithBytes: &acl length: sizeof(acl) ], AVChannelLayoutKey,
[NSNumber numberWithInt:64000], AVEncoderBitRateKey,
nil ];
audioWriterInput = [AVAssetWriterInput assetWriterInputWithMediaType:AVMediaTypeAudio outputSettings:audioSettings];
audioWriterInput.expectsMediaDataInRealTime = YES;
//add input
[videoWriter addInput:videoWriterInput];
[videoWriter addInput:audioWriterInput];
return YES;
}
- (void) cleanupWriter {
[videoWriter release];
videoWriter = nil;
avAdaptor = nil;
videoWriterInput = nil;
startedAt = nil;
audioWriterInput = nil;
}
- (void) encodeFrameAtTime:(CMTime)timestamp
{
if(!isRecording) return;
if(videoWriter == nil) return;
if(videoWriter.status == AVAssetWriterStatusFailed)
{
return;
}
if(videoWriter.status != AVAssetWriterStatusWriting)
{
if(videoWriter.status != AVAssetWriterStatusUnknown)
return;
[videoWriter startWriting];
[videoWriter startSessionAtSourceTime:timestamp];
startTime = CMTimeGetSeconds(timestamp);
}
timestamp = CMTimeMakeWithSeconds(startTime + CMTimeGetSeconds(timestamp), 1000);
[self writeVideoFrameAtTime:timestamp];
}
-(void) writeVideoFrameAtTime:(CMTime)time {
if (![videoWriterInput isReadyForMoreMediaData])
{
}
else
{
/*
CVPixelBufferRef manipulation omitted...
*/
{
BOOL success = [avAdaptor appendPixelBuffer:pixelBuffer withPresentationTime:time];
if(videoWriter.status == AVAssetWriterStatusFailed) NSLog(@"Failed: %@", videoWriter.error);
if (!success) NSLog(@"Warning: Unable to write buffer to video");
}
CVPixelBufferRelease(pixelBuffer);
CGImageRelease(cgImage);
}
}
-(void) encodeAudioFrame:(CMSampleBufferRef)buffer
{
if(!isRecording) return;
CMTime timestamp = CMSampleBufferGetPresentationTimeStamp(buffer);
if(videoWriter.status != AVAssetWriterStatusWriting)
{
//Wait for video thread to start the writer
return;
}
if(![audioWriterInput isReadyForMoreMediaData])
return;
//*
NSTimeInterval offset = [[NSDate date] timeIntervalSinceDate:startedAt];
if(audioDelta == -1)
{
audioDelta = offset - CMTimeGetSeconds(timestamp);
}
//Adjusts CMSampleBufferRef's timestamp to match the video stream's zero-based timestamp
CMItemCount count;
CMTime newTimestamp = CMTimeMakeWithSeconds(CMTimeGetSeconds(timestamp) + audioDelta - pauseDelta, 1000);
CMSampleBufferGetSampleTimingInfoArray(buffer, 0, nil, &count);
CMSampleTimingInfo* pInfo = malloc(sizeof(CMSampleTimingInfo) * count);
CMSampleBufferGetSampleTimingInfoArray(buffer, count, pInfo, &count);
for(CMItemCount i = 0; i < count; i++)
{
pInfo[i].decodeTimeStamp = newTimestamp;
pInfo[i].presentationTimeStamp = newTimestamp;
}
CMSampleBufferRef newBuffer;
CMSampleBufferCreateCopyWithNewTiming(kCFAllocatorDefault, buffer, count, pInfo, &newBuffer);
free(pInfo);
timestamp = CMSampleBufferGetPresentationTimeStamp(newBuffer);
BOOL res = [audioWriterInput appendSampleBuffer:newBuffer];
}
- (void) completeRecordingSession {
@autoreleasepool {
if(videoWriter.status != AVAssetWriterStatusWriting)
{
while (videoWriter.status == AVAssetWriterStatusUnknown)
{
[NSThread sleepForTimeInterval:0.5f];
}
int status = videoWriter.status;
while (status == AVAssetWriterStatusUnknown)
{
NSLog(@"Waiting...");
[NSThread sleepForTimeInterval:0.5f];
status = videoWriter.status;
}
}
@synchronized(self)
{
[videoWriter finishWriting];
[self cleanupWriter];
}
}
}
-(void) captureOutput:(AVCaptureOutput *)captureOutput didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer fromConnection:(AVCaptureConnection *)connection
{
if(!CMSampleBufferDataIsReady(sampleBuffer))
return;
@autoreleasepool {
if(captureOutput == audioOutput)
{
if(isRecording && !isPaused)
{
[self encodeAudioFrame:sampleBuffer];
}
}
}
}
您的控制檯是否向您發送了垃圾郵件，說明您收到錯誤-12737，也稱爲kCMSampleBufferError_ArrayTooSmall？如果是這樣，我有相同的錯誤:(將報告回來，如果我得到任何東西... – nevyn
你能解決這個問題嗎？我有同樣的問題。 – omarojo
同樣的問題在這裏以及。@omarojo *你*能夠解決這個問題？ – user1244109