HX_RESULT HXAudioConfiguratorAAC::ExtractDecoderInfo(UINT32 cfgType,
const void* config,
UINT32 nBytes,
CAudioSpecificConfig* pASConfig)
{
HX_RESULT result = HXR_OK;
struct BITSTREAM *pBitStream = NULL;
if(cfgType != eAACConfigAudioSpecificCfg)
{
result = HXR_INVALID_PARAMETER;
}
if(SUCCEEDED(result))
{
// allocate bit stream
if(newBitstream(&pBitStream, 8*nBytes))
{
result = HXR_OUTOFMEMORY;
}
}
if(SUCCEEDED(result))
{
// decode bit stream into configuration structure
feedBitstream(pBitStream, (unsigned char*)config, 8*nBytes) ;
setAtBitstream(pBitStream, 0, 1);
result = pASConfig->Read(*pBitStream);
}
if(pBitStream)
{
// deallocate bit stream
deleteBitstream(pBitStream);
}
return result;
}
/*
* aac_decode_init
*/
HX_RESULT
aac_decode_init(void* pInitParams,
UINT32 ulInitParamsSize,
ra_format_info* pStreamInfo,
void** pDecode,
void* pUserMem,
rm_malloc_func_ptr fpMalloc,
rm_free_func_ptr fpFree)
{
HX_RESULT result = HXR_OK;
aac_decode* pDec;
AACFrameInfo *frameInfo;
ga_config_data configData;
UCHAR *pData;
UCHAR *inBuf;
INT16 *temp;
UINT32 numBytes, numBits;
UINT32 cfgType;
/* for MP4 bitstream parsing */
struct BITSTREAM *pBs = 0;
/* allocate the aac_decode struct */
pDec = (aac_decode*) fpMalloc(pUserMem, sizeof(aac_decode));
if (pDec == HXNULL)
{
return HXR_OUTOFMEMORY;
}
memset(pDec, 0, sizeof(aac_decode));
*pDecode = (void *)pDec;
/* allocate the frame info struct */
pDec->pFrameInfo = fpMalloc(pUserMem, sizeof(AACFrameInfo));
frameInfo = (AACFrameInfo *) pDec->pFrameInfo;
/* allocate the decoder backend instance */
pDec->pDecoder = AACInitDecoder(1);
if (pDec->pFrameInfo == HXNULL || pDec->pDecoder == HXNULL)
{
return HXR_OUTOFMEMORY;
}
/* save the stream info and init data we'll need later */
pDec->ulNumChannels = (UINT32)pStreamInfo->usNumChannels;
pDec->ulBlockSize = pStreamInfo->ulGranularity;
pDec->ulFrameSize = pStreamInfo->ulBitsPerFrame;
pDec->ulFramesPerBlock = pDec->ulBlockSize / pDec->ulFrameSize;
/* output frame size is doubled for safety in case of implicit SBR */
pDec->ulSamplesPerFrame = 1024*pStreamInfo->usNumChannels*2;
pDec->ulSampleRateCore = pStreamInfo->ulSampleRate;
pDec->ulSampleRateOut = pStreamInfo->ulActualRate;
if (pStreamInfo->ulOpaqueDataSize < 1)
{
return HXR_FAIL; /* insufficient config data */
}
/* get the config data */
pData = (UCHAR *)pStreamInfo->pOpaqueData;
cfgType = pData[0];
inBuf = pData + 1;
numBytes = pStreamInfo->ulOpaqueDataSize - 1;
if (cfgType == 1) /* ADTS Frame */
{
/* allocate temp buffer for decoding first ADTS frame */
temp = (INT16 *)fpMalloc(pUserMem, sizeof(INT16) * pDec->ulSamplesPerFrame);
if (temp == HXNULL)
{
return HXR_OUTOFMEMORY;
}
else
{
/* decode ADTS frame from opaque data to get config data */
result = AACDecode(pDec->pDecoder, &inBuf, (INT32*)&numBytes, temp);
/* free the temp buffer */
fpFree(pUserMem, temp);
}
if (result == HXR_OK)
{
/* get the config data struct from the decoder */
AACGetLastFrameInfo(pDec->pDecoder, frameInfo);
pDec->ulNumChannels = frameInfo->nChans;
pDec->ulSamplesPerFrame = frameInfo->outputSamps;
pDec->ulSampleRateCore = frameInfo->sampRateCore;
pDec->ulSampleRateOut = frameInfo->sampRateOut;
pDec->bSBR = (pDec->ulSampleRateCore != pDec->ulSampleRateOut);
}
}
else if (cfgType == 2) /* MP4 Audio Specific Config Data */
{
numBits = numBytes*8;
if (newBitstream(&pBs, numBits, pUserMem, fpMalloc))
{
return HXR_FAIL;
}
feedBitstream(pBs, (const UCHAR *)inBuf, numBits);
setAtBitstream(pBs, 0, 1);
result = ga_config_get_data(pBs, &configData);
deleteBitstream(pBs, pUserMem, fpFree);
if (result != HXR_OK) /* config data error */
{
return HXR_FAIL;
}
pDec->ulNumChannels = configData.numChannels;
pDec->ulSampleRateCore = configData.samplingFrequency;
pDec->ulSampleRateOut = configData.extensionSamplingFrequency;
pDec->bSBR = configData.bSBR;
/* ulSamplesPerFrame is set to the maximum possible output length.
* The config data has the initial output length, which might
* be doubled once the first frame is handed in (if AAC+ is
* signalled implicitly).
*/
pDec->ulSamplesPerFrame = 2*configData.frameLength*configData.numChannels;
/* setup decoder to handle raw data blocks */
frameInfo->nChans = pDec->ulNumChannels;
frameInfo->sampRateCore = pDec->ulSampleRateCore;
/* see MPEG4 spec for index of each object type */
if (configData.audioObjectType == 2)
frameInfo->profile = AAC_PROFILE_LC;
else if (configData.audioObjectType == 1)
frameInfo->profile = AAC_PROFILE_MP;
else if (configData.audioObjectType == 3)
frameInfo->profile = AAC_PROFILE_SSR;
else
frameInfo->profile = AAC_PROFILE_LC; /* don't know - assume LC */
frameInfo->audio_send_by_frame=0;
}
else /* unsupported config type */
{
return HXR_FAIL;
}
/* make certain that all the channels can be handled */
if (pDec->ulNumChannels > AAC_MAX_NCHANS) {
return HXR_UNSUPPORTED_AUDIO;
}
/* set the channel mask - custom maps not supported */
switch (pDec->ulNumChannels) {
case 1: pDec->ulChannelMask = 0x00004; /* FC */
case 2: pDec->ulChannelMask = 0x00003; /* FL,FR */
case 3: pDec->ulChannelMask = 0x00007; /* FL,FR,FC */
case 4: pDec->ulChannelMask = 0x00107; /* FL,FR,FC,BC */
case 5: pDec->ulChannelMask = 0x00037; /* FL,FR,FC,BL,BR */
case 6: pDec->ulChannelMask = 0x0003F; /* FL,FR,FC,LF,BL,BR */
default: pDec->ulChannelMask = 0xFFFFF; /* Unknown */
}
/* set the delay samples */
pDec->ulDelayRemaining = pDec->ulSamplesPerFrame;
/* set decoder to handle raw data blocks */
AACSetRawBlockParams(pDec->pDecoder, 0, frameInfo);
return HXR_OK;
}
