I'm trying to decode a raw stream of .H264 video data but I can't find a way to create a proper
- (void)decodeFrameWithNSData:(NSData*)data presentationTime:
(CMTime)presentationTime
{
@autoreleasepool {
CMSampleBufferRef sampleBuffer = NULL;
CMBlockBufferRef blockBuffer = NULL;
VTDecodeInfoFlags infoFlags;
int sourceFrame;
if( dSessionRef == NULL )
[self createDecompressionSession];
CMSampleTimingInfo timingInfo ;
timingInfo.presentationTimeStamp = presentationTime;
timingInfo.duration = CMTimeMake(1,100000000);
timingInfo.decodeTimeStamp = kCMTimeInvalid;
//Creates block buffer from NSData
OSStatus status = CMBlockBufferCreateWithMemoryBlock(CFAllocatorGetDefault(), (void*)data.bytes,data.length*sizeof(char), CFAllocatorGetDefault(), NULL, 0, data.length*sizeof(char), 0, &blockBuffer);
//Creates CMSampleBuffer to feed decompression session
status = CMSampleBufferCreateReady(CFAllocatorGetDefault(), blockBuffer,self.encoderVideoFormat,1,1,&timingInfo, 0, 0, &sampleBuffer);
status = VTDecompressionSessionDecodeFrame(dSessionRef,sampleBuffer, kVTDecodeFrame_1xRealTimePlayback, &sourceFrame,&infoFlags);
if(status != noErr) {
NSLog(@"Decode with data error %d",status);
}
}
}
At the end of the call I'm getting -12911 error in VTDecompressionSessionDecodeFrame that translates to kVTVideoDecoderMalfunctionErr which after reading this [post] pointed me that I should make a VideoFormatDescriptor using CMVideoFormatDescriptionCreateFromH264ParameterSets. But how can I create a new VideoFormatDescription if I don't have information of the currentSps or currentPps? How can I get that information from my raw .H264 streaming?
CMFormatDescriptionRef decoderFormatDescription; const uint8_t* const parameterSetPointers[2] = { (const uint8_t*)[currentSps bytes], (const uint8_t*)[currentPps bytes] }; const size_t parameterSetSizes[2] = { [currentSps length], [currentPps length] }; status = CMVideoFormatDescriptionCreateFromH264ParameterSets(NULL, 2, parameterSetPointers, parameterSetSizes, 4, &decoderFormatDescription);
Thanks in advance,
Marcos
[post] : Decoding H264 VideoToolkit API fails with Error -8971 in VTDecompressionSessionCreate
from Decoding H264 VideoToolkit API fails with Error -12911 in VTDecompressionSessionDecodeFrame
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