INT transportDec_GetBufferFullness( const HANDLE_TRANSPORTDEC hTp ) { INT bufferFullness = -1; switch (hTp->transportFmt) { case TT_MP4_ADTS: if (hTp->parser.adts.bs.adts_fullness != 0x7ff) { bufferFullness = hTp->parser.adts.bs.frame_length*8 + hTp->parser.adts.bs.adts_fullness * 32 * getNumberOfEffectiveChannels(hTp->parser.adts.bs.channel_config); } break; case TT_MP4_LOAS: case TT_MP4_LATM_MCP0: case TT_MP4_LATM_MCP1: if (hTp->parser.latm.m_linfo[0][0].m_bufferFullness != 0xff) { bufferFullness = hTp->parser.latm.m_linfo[0][0].m_bufferFullness; } break; default: break; } return bufferFullness; }
TRANSPORTDEC_ERROR adtsRead_DecodeHeader( HANDLE_ADTS pAdts, CSAudioSpecificConfig *pAsc, HANDLE_FDK_BITSTREAM hBs, const INT ignoreBufferFullness ) { INT crcReg; INT valBits; INT cmp_buffer_fullness; int i, adtsHeaderLength; STRUCT_ADTS_BS bs; #ifdef TP_PCE_ENABLE CProgramConfig oldPce; /* Store the old PCE temporarily. Maybe we'll need it later if we have channelConfig=0 and no PCE in this frame. */ FDKmemcpy(&oldPce, &pAsc->m_progrConfigElement, sizeof(CProgramConfig)); #endif valBits = FDKgetValidBits(hBs); #ifndef ANDROID_DEFAULT_CODE if (valBits <= ADTS_HEADERLENGTH) return TRANSPORTDEC_NOT_ENOUGH_BITS; #endif /* adts_fixed_header */ bs.mpeg_id = FDKreadBits(hBs, Adts_Length_Id); bs.layer = FDKreadBits(hBs, Adts_Length_Layer); bs.protection_absent = FDKreadBits(hBs, Adts_Length_ProtectionAbsent); bs.profile = FDKreadBits(hBs, Adts_Length_Profile); bs.sample_freq_index = FDKreadBits(hBs, Adts_Length_SamplingFrequencyIndex); bs.private_bit = FDKreadBits(hBs, Adts_Length_PrivateBit); bs.channel_config = FDKreadBits(hBs, Adts_Length_ChannelConfiguration); bs.original = FDKreadBits(hBs, Adts_Length_OriginalCopy); bs.home = FDKreadBits(hBs, Adts_Length_Home); /* adts_variable_header */ bs.copyright_id = FDKreadBits(hBs, Adts_Length_CopyrightIdentificationBit); bs.copyright_start = FDKreadBits(hBs, Adts_Length_CopyrightIdentificationStart); bs.frame_length = FDKreadBits(hBs, Adts_Length_FrameLength); bs.adts_fullness = FDKreadBits(hBs, Adts_Length_BufferFullness); bs.num_raw_blocks = FDKreadBits(hBs, Adts_Length_NumberOfRawDataBlocksInFrame); bs.num_pce_bits = 0; adtsHeaderLength = ADTS_HEADERLENGTH; if (!bs.protection_absent) { FDKcrcReset(&pAdts->crcInfo); FDKpushBack(hBs, 56); /* complete fixed and variable header! */ crcReg = FDKcrcStartReg(&pAdts->crcInfo, hBs, 0); FDKpushFor(hBs, 56); } if (! bs.protection_absent && bs.num_raw_blocks>0) { for (i=0; i<bs.num_raw_blocks; i++) { pAdts->rawDataBlockDist[i] = (USHORT)FDKreadBits(hBs, 16); adtsHeaderLength += 16; } /* Change raw data blocks to delta values */ pAdts->rawDataBlockDist[bs.num_raw_blocks] = bs.frame_length - 7 - bs.num_raw_blocks*2 - 2 ; for (i=bs.num_raw_blocks; i>0; i--) { pAdts->rawDataBlockDist[i] -= pAdts->rawDataBlockDist[i-1]; } } /* adts_error_check */ if (!bs.protection_absent) { USHORT crc_check; FDKcrcEndReg(&pAdts->crcInfo, hBs, crcReg); crc_check = FDKreadBits(hBs, Adts_Length_CrcCheck); adtsHeaderLength += Adts_Length_CrcCheck; pAdts->crcReadValue = crc_check; /* Check header CRC in case of multiple raw data blocks */ if (bs.num_raw_blocks > 0) { if (pAdts->crcReadValue != FDKcrcGetCRC(&pAdts->crcInfo)) { return TRANSPORTDEC_CRC_ERROR; } /* Reset CRC for the upcoming raw_data_block() */ FDKcrcReset(&pAdts->crcInfo); } } /* check if valid header */ if ( (bs.layer != 0) || // we only support MPEG ADTS (bs.sample_freq_index >= 13) // we only support 96kHz - 7350kHz ) { FDKpushFor(hBs, bs.frame_length * 8); // try again one frame later return TRANSPORTDEC_UNSUPPORTED_FORMAT; } /* special treatment of id-bit */ if ( (bs.mpeg_id == 0) && (pAdts->decoderCanDoMpeg4 == 0) ) { /* MPEG-2 decoder cannot play MPEG-4 bitstreams */ FDKpushFor(hBs, bs.frame_length * 8); // try again one frame later return TRANSPORTDEC_UNSUPPORTED_FORMAT; } if (!ignoreBufferFullness) { cmp_buffer_fullness = bs.frame_length*8 + bs.adts_fullness*32*getNumberOfEffectiveChannels(bs.channel_config); /* Evaluate buffer fullness */ if (bs.adts_fullness != 0x7FF) { if (pAdts->BufferFullnesStartFlag) { if ( valBits < cmp_buffer_fullness ) { /* Condition for start of decoding is not fulfilled */ /* The current frame will not be decoded */ FDKpushBack(hBs, adtsHeaderLength); if ( (cmp_buffer_fullness+adtsHeaderLength) > ((TRANSPORTDEC_INBUF_SIZE<<3)-7) ) { return TRANSPORTDEC_SYNC_ERROR; } else { return TRANSPORTDEC_NOT_ENOUGH_BITS; } } else { pAdts->BufferFullnesStartFlag = 0; } } } } /* Get info from ADTS header */ AudioSpecificConfig_Init(pAsc); pAsc->m_aot = (AUDIO_OBJECT_TYPE)(bs.profile + 1); pAsc->m_samplingFrequencyIndex = bs.sample_freq_index; pAsc->m_samplingFrequency = SamplingRateTable[bs.sample_freq_index]; pAsc->m_channelConfiguration = bs.channel_config; pAsc->m_samplesPerFrame = 1024; #ifdef TP_PCE_ENABLE if (bs.channel_config == 0) { int pceBits = 0; UINT alignAnchor = FDKgetValidBits(hBs); if (FDKreadBits(hBs,3) == ID_PCE) { /* Got luck! Parse the PCE */ int crcReg; crcReg = adtsRead_CrcStartReg(pAdts, hBs, 0); CProgramConfig_Read(&pAsc->m_progrConfigElement, hBs, alignAnchor); adtsRead_CrcEndReg(pAdts, hBs, crcReg); pceBits = alignAnchor - FDKgetValidBits(hBs); /* store the number of PCE bits */ bs.num_pce_bits = pceBits; } else { /* No PCE in this frame! Push back the ID tag bits. */ FDKpushBack(hBs,3); /* Encoders do not have to write a PCE in each frame. So if we already have a valid PCE we have to use it. */ if ( oldPce.isValid && (bs.sample_freq_index == pAdts->bs.sample_freq_index) /* we could compare the complete fixed header (bytes) here! */ && (bs.channel_config == pAdts->bs.channel_config) /* == 0 */ && (bs.mpeg_id == pAdts->bs.mpeg_id) ) { /* Restore previous PCE which is still valid */ FDKmemcpy(&pAsc->m_progrConfigElement, &oldPce, sizeof(CProgramConfig)); } else if (bs.mpeg_id == 0) { /* If not it seems that we have a implicit channel configuration. This mode is not allowed in the context of ISO/IEC 14496-3. Skip this frame and try the next one. */ FDKpushFor(hBs, (bs.frame_length<<3) - adtsHeaderLength - 3); return TRANSPORTDEC_UNSUPPORTED_FORMAT; } /* else { ISO/IEC 13818-7 implicit channel mapping is allowed. So just open the box of chocolates to see what we got. } */ } } #endif /* TP_PCE_ENABLE */ /* Copy bit stream data struct to persistent memory now, once we passed all sanity checks above. */ FDKmemcpy(&pAdts->bs, &bs, sizeof(STRUCT_ADTS_BS)); return TRANSPORTDEC_OK; }