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authorDave Burke <daveburke@google.com>2012-04-17 09:51:45 -0700
committerDave Burke <daveburke@google.com>2012-04-17 23:04:43 -0700
commit9bf37cc9712506b2483650c82d3c41152337ef7e (patch)
tree77db44e2bae06e3d144b255628be2b7a55c581d3 /libMpegTPDec/src/tpdec_adts.cpp
parenta37315fe10ee143d6d0b28c19d41a476a23e63ea (diff)
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Fraunhofer AAC codec.
License boilerplate update to follow. Change-Id: I2810460c11a58b6d148d84673cc031f3685e79b5
Diffstat (limited to 'libMpegTPDec/src/tpdec_adts.cpp')
-rw-r--r--libMpegTPDec/src/tpdec_adts.cpp326
1 files changed, 326 insertions, 0 deletions
diff --git a/libMpegTPDec/src/tpdec_adts.cpp b/libMpegTPDec/src/tpdec_adts.cpp
new file mode 100644
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--- /dev/null
+++ b/libMpegTPDec/src/tpdec_adts.cpp
@@ -0,0 +1,326 @@
+/***************************** MPEG-4 AAC Decoder **************************
+
+ (C) Copyright Fraunhofer IIS (2004)
+ All Rights Reserved
+
+ Please be advised that this software and/or program delivery is
+ Confidential Information of Fraunhofer and subject to and covered by the
+
+ Fraunhofer IIS Software Evaluation Agreement
+ between Google Inc. and Fraunhofer
+ effective and in full force since March 1, 2012.
+
+ You may use this software and/or program only under the terms and
+ conditions described in the above mentioned Fraunhofer IIS Software
+ Evaluation Agreement. Any other and/or further use requires a separate agreement.
+
+
+ $Id$
+ Author(s): Josef Hoepfl
+ Description: ADTS interface
+
+ This software and/or program is protected by copyright law and international
+ treaties. Any reproduction or distribution of this software and/or program,
+ or any portion of it, may result in severe civil and criminal penalties, and
+ will be prosecuted to the maximum extent possible under law.
+
+******************************************************************************/
+
+#include "tpdec_adts.h"
+
+
+#include "FDK_bitstream.h"
+
+
+
+void adtsRead_CrcInit(HANDLE_ADTS pAdts) /*!< pointer to adts crc info stucture */
+{
+ FDKcrcInit(&pAdts->crcInfo, 0x8005, 0xFFFF, 16);
+}
+
+int adtsRead_CrcStartReg(
+ HANDLE_ADTS pAdts, /*!< pointer to adts stucture */
+ HANDLE_FDK_BITSTREAM hBs, /*!< handle to current bit buffer structure */
+ int mBits /*!< number of bits in crc region */
+ )
+{
+ if (pAdts->bs.protection_absent) {
+ return 0;
+ }
+
+ return ( FDKcrcStartReg(&pAdts->crcInfo, hBs, mBits) );
+
+}
+
+void adtsRead_CrcEndReg(
+ HANDLE_ADTS pAdts, /*!< pointer to adts crc info stucture */
+ HANDLE_FDK_BITSTREAM hBs, /*!< handle to current bit buffer structure */
+ int reg /*!< crc region */
+ )
+{
+ if (pAdts->bs.protection_absent == 0)
+ {
+ FDKcrcEndReg(&pAdts->crcInfo, hBs, reg);
+ }
+}
+
+TRANSPORTDEC_ERROR adtsRead_CrcCheck( HANDLE_ADTS pAdts )
+{
+ TRANSPORTDEC_ERROR ErrorStatus = TRANSPORTDEC_OK;
+ USHORT crc;
+
+ if (pAdts->bs.protection_absent)
+ return TRANSPORTDEC_OK;
+
+ crc = FDKcrcGetCRC(&pAdts->crcInfo);
+ if (crc != pAdts->crcReadValue)
+ {
+ return (TRANSPORTDEC_CRC_ERROR);
+ }
+
+ return (ErrorStatus);
+}
+
+
+
+#define Adts_Length_SyncWord 12
+#define Adts_Length_Id 1
+#define Adts_Length_Layer 2
+#define Adts_Length_ProtectionAbsent 1
+#define Adts_Length_Profile 2
+#define Adts_Length_SamplingFrequencyIndex 4
+#define Adts_Length_PrivateBit 1
+#define Adts_Length_ChannelConfiguration 3
+#define Adts_Length_OriginalCopy 1
+#define Adts_Length_Home 1
+#define Adts_Length_CopyrightIdentificationBit 1
+#define Adts_Length_CopyrightIdentificationStart 1
+#define Adts_Length_FrameLength 13
+#define Adts_Length_BufferFullness 11
+#define Adts_Length_NumberOfRawDataBlocksInFrame 2
+#define Adts_Length_CrcCheck 16
+
+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);
+
+ /* 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;
+}
+
+int adtsRead_GetRawDataBlockLength(
+ HANDLE_ADTS pAdts,
+ INT blockNum
+ )
+{
+ int length;
+
+ if (pAdts->bs.num_raw_blocks == 0) {
+ length = (pAdts->bs.frame_length - 7) << 3; /* aac_frame_length subtracted by the header size (7 bytes). */
+ if (pAdts->bs.protection_absent == 0)
+ length -= 16; /* substract 16 bit CRC */
+ } else {
+ if (pAdts->bs.protection_absent) {
+ length = -1; /* raw data block length is unknown */
+ } else {
+ if (blockNum < 0 || blockNum > 3) {
+ return TRANSPORTDEC_INVALID_PARAMETER;
+ }
+ length = (pAdts->rawDataBlockDist[blockNum] << 3) - 16;
+ }
+ }
+ if (blockNum == 0) {
+ length -= pAdts->bs.num_pce_bits;
+ }
+ return length;
+}
+
+