summaryrefslogtreecommitdiffstats
path: root/libSBRdec/src/psbitdec.cpp
diff options
context:
space:
mode:
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 /libSBRdec/src/psbitdec.cpp
parenta37315fe10ee143d6d0b28c19d41a476a23e63ea (diff)
downloadfdk-aac-9bf37cc9712506b2483650c82d3c41152337ef7e.tar.gz
fdk-aac-9bf37cc9712506b2483650c82d3c41152337ef7e.tar.bz2
fdk-aac-9bf37cc9712506b2483650c82d3c41152337ef7e.zip
Fraunhofer AAC codec.
License boilerplate update to follow. Change-Id: I2810460c11a58b6d148d84673cc031f3685e79b5
Diffstat (limited to 'libSBRdec/src/psbitdec.cpp')
-rw-r--r--libSBRdec/src/psbitdec.cpp536
1 files changed, 536 insertions, 0 deletions
diff --git a/libSBRdec/src/psbitdec.cpp b/libSBRdec/src/psbitdec.cpp
new file mode 100644
index 0000000..0a5687a
--- /dev/null
+++ b/libSBRdec/src/psbitdec.cpp
@@ -0,0 +1,536 @@
+/****************************************************************************
+
+ (C) Copyright Fraunhofer IIS (2005)
+ 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.
+
+
+ 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.
+
+ $Id$
+
+*******************************************************************************/
+
+#include "psbitdec.h"
+
+
+#include "sbr_rom.h"
+#include "huff_dec.h"
+
+/* PS dec privat functions */
+SBR_ERROR ResetPsDec(HANDLE_PS_DEC h_ps_d);
+void ResetPsDeCor (HANDLE_PS_DEC h_ps_d);
+
+/***************************************************************************/
+/*!
+ \brief huffman decoding by codebook table
+
+ \return index of huffman codebook table
+
+****************************************************************************/
+static SCHAR
+decode_huff_cw (Huffman h, /*!< pointer to huffman codebook table */
+ HANDLE_FDK_BITSTREAM hBitBuf, /*!< Handle to Bitbuffer */
+ int *length) /*!< length of huffman codeword (or NULL) */
+{
+ UCHAR bit = 0;
+ SCHAR index = 0;
+ UCHAR bitCount = 0;
+
+ while (index >= 0) {
+ bit = FDKreadBits (hBitBuf, 1);
+ bitCount++;
+ index = h[index][bit];
+ }
+ if (length) {
+ *length = bitCount;
+ }
+ return( index+64 ); /* Add offset */
+}
+
+/***************************************************************************/
+/*!
+ \brief helper function - limiting of value to min/max values
+
+ \return limited value
+
+****************************************************************************/
+
+static SCHAR
+limitMinMax(SCHAR i,
+ SCHAR min,
+ SCHAR max)
+{
+ if (i<min)
+ return min;
+ else if (i>max)
+ return max;
+ else
+ return i;
+}
+
+/***************************************************************************/
+/*!
+ \brief Decodes delta values in-place and updates
+ data buffers according to quantization classes.
+
+ When delta coded in frequency the first element is deltacode from zero.
+ aIndex buffer is decoded from delta values to actual values.
+
+ \return none
+
+****************************************************************************/
+static void
+deltaDecodeArray(SCHAR enable,
+ SCHAR *aIndex, /*!< ICC/IID parameters */
+ SCHAR *aPrevFrameIndex, /*!< ICC/IID parameters of previous frame */
+ SCHAR DtDf,
+ UCHAR nrElements, /*!< as conveyed in bitstream */
+ /*!< output array size: nrElements*stride */
+ UCHAR stride, /*!< 1=dflt, 2=half freq. resolution */
+ SCHAR minIdx,
+ SCHAR maxIdx)
+{
+ int i;
+
+ /* Delta decode */
+ if ( enable==1 ) {
+ if (DtDf == 0) { /* Delta coded in freq */
+ aIndex[0] = 0 + aIndex[0];
+ aIndex[0] = limitMinMax(aIndex[0],minIdx,maxIdx);
+ for (i = 1; i < nrElements; i++) {
+ aIndex[i] = aIndex[i-1] + aIndex[i];
+ aIndex[i] = limitMinMax(aIndex[i],minIdx,maxIdx);
+ }
+ }
+ else { /* Delta time */
+ for (i = 0; i < nrElements; i++) {
+ aIndex[i] = aPrevFrameIndex[i*stride] + aIndex[i];
+ aIndex[i] = limitMinMax(aIndex[i],minIdx,maxIdx);
+ }
+ }
+ }
+ else { /* No data is sent, set index to zero */
+ for (i = 0; i < nrElements; i++) {
+ aIndex[i] = 0;
+ }
+ }
+ if (stride==2) {
+ for (i=nrElements*stride-1; i>0; i--) {
+ aIndex[i] = aIndex[i>>1];
+ }
+ }
+}
+
+/***************************************************************************/
+/*!
+ \brief Mapping of ICC/IID parameters to 20 stereo bands
+
+ \return none
+
+****************************************************************************/
+static void map34IndexTo20 (SCHAR *aIndex, /*!< decoded ICC/IID parameters */
+ UCHAR noBins) /*!< number of stereo bands */
+{
+ aIndex[0] = (2*aIndex[0]+aIndex[1])/3;
+ aIndex[1] = (aIndex[1]+2*aIndex[2])/3;
+ aIndex[2] = (2*aIndex[3]+aIndex[4])/3;
+ aIndex[3] = (aIndex[4]+2*aIndex[5])/3;
+ aIndex[4] = (aIndex[6]+aIndex[7])/2;
+ aIndex[5] = (aIndex[8]+aIndex[9])/2;
+ aIndex[6] = aIndex[10];
+ aIndex[7] = aIndex[11];
+ aIndex[8] = (aIndex[12]+aIndex[13])/2;
+ aIndex[9] = (aIndex[14]+aIndex[15])/2;
+ aIndex[10] = aIndex[16];
+ /* For IPD/OPD it stops here */
+
+ if (noBins == NO_HI_RES_BINS)
+ {
+ aIndex[11] = aIndex[17];
+ aIndex[12] = aIndex[18];
+ aIndex[13] = aIndex[19];
+ aIndex[14] = (aIndex[20]+aIndex[21])/2;
+ aIndex[15] = (aIndex[22]+aIndex[23])/2;
+ aIndex[16] = (aIndex[24]+aIndex[25])/2;
+ aIndex[17] = (aIndex[26]+aIndex[27])/2;
+ aIndex[18] = (aIndex[28]+aIndex[29]+aIndex[30]+aIndex[31])/4;
+ aIndex[19] = (aIndex[32]+aIndex[33])/2;
+ }
+}
+
+/***************************************************************************/
+/*!
+ \brief Decodes delta coded IID, ICC, IPD and OPD indices
+
+ \return PS processing flag. If set to 1
+
+****************************************************************************/
+int
+DecodePs( struct PS_DEC *h_ps_d, /*!< PS handle */
+ const UCHAR frameError ) /*!< Flag telling that frame had errors */
+{
+ MPEG_PS_BS_DATA *pBsData;
+ UCHAR gr, env;
+ int bPsHeaderValid, bPsDataAvail;
+
+ /* Shortcuts to avoid deferencing and keep the code readable */
+ pBsData = &h_ps_d->bsData[h_ps_d->processSlot].mpeg;
+ bPsHeaderValid = pBsData->bPsHeaderValid;
+ bPsDataAvail = (h_ps_d->bPsDataAvail[h_ps_d->processSlot] == ppt_mpeg) ? 1 : 0;
+
+ /***************************************************************************************
+ * Decide whether to process or to conceal PS data or not. */
+
+ if ( ( h_ps_d->psDecodedPrv && !frameError && !bPsDataAvail)
+ || (!h_ps_d->psDecodedPrv && (frameError || !bPsDataAvail || !bPsHeaderValid)) ) {
+ /* Don't apply PS processing.
+ * Declare current PS header and bitstream data invalid. */
+ pBsData->bPsHeaderValid = 0;
+ h_ps_d->bPsDataAvail[h_ps_d->processSlot] = ppt_none;
+ return (0);
+ }
+
+ if (frameError || !bPsHeaderValid)
+ { /* no new PS data available (e.g. frame loss) */
+ /* => keep latest data constant (i.e. FIX with noEnv=0) */
+ pBsData->noEnv = 0;
+ }
+
+ /***************************************************************************************
+ * Decode bitstream payload or prepare parameter for concealment:
+ */
+ for (env=0; env<pBsData->noEnv; env++) {
+ SCHAR *aPrevIidIndex;
+ SCHAR *aPrevIccIndex;
+
+ UCHAR noIidSteps = pBsData->bFineIidQ?NO_IID_STEPS_FINE:NO_IID_STEPS;
+
+ if (env==0) {
+ aPrevIidIndex = h_ps_d->specificTo.mpeg.aIidPrevFrameIndex;
+ aPrevIccIndex = h_ps_d->specificTo.mpeg.aIccPrevFrameIndex;
+ }
+ else {
+ aPrevIidIndex = pBsData->aaIidIndex[env-1];
+ aPrevIccIndex = pBsData->aaIccIndex[env-1];
+ }
+
+ deltaDecodeArray(pBsData->bEnableIid,
+ pBsData->aaIidIndex[env],
+ aPrevIidIndex,
+ pBsData->abIidDtFlag[env],
+ FDK_sbrDecoder_aNoIidBins[pBsData->freqResIid],
+ (pBsData->freqResIid)?1:2,
+ -noIidSteps,
+ noIidSteps);
+
+ deltaDecodeArray(pBsData->bEnableIcc,
+ pBsData->aaIccIndex[env],
+ aPrevIccIndex,
+ pBsData->abIccDtFlag[env],
+ FDK_sbrDecoder_aNoIccBins[pBsData->freqResIcc],
+ (pBsData->freqResIcc)?1:2,
+ 0,
+ NO_ICC_STEPS-1);
+ } /* for (env=0; env<pBsData->noEnv; env++) */
+
+ /* handling of FIX noEnv=0 */
+ if (pBsData->noEnv==0) {
+ /* set noEnv=1, keep last parameters or force 0 if not enabled */
+ pBsData->noEnv = 1;
+
+ if (pBsData->bEnableIid) {
+ for (gr = 0; gr < NO_HI_RES_IID_BINS; gr++) {
+ pBsData->aaIidIndex[pBsData->noEnv-1][gr] =
+ h_ps_d->specificTo.mpeg.aIidPrevFrameIndex[gr];
+ }
+ }
+ else {
+ for (gr = 0; gr < NO_HI_RES_IID_BINS; gr++) {
+ pBsData->aaIidIndex[pBsData->noEnv-1][gr] = 0;
+ }
+ }
+
+ if (pBsData->bEnableIcc) {
+ for (gr = 0; gr < NO_HI_RES_ICC_BINS; gr++) {
+ pBsData->aaIccIndex[pBsData->noEnv-1][gr] =
+ h_ps_d->specificTo.mpeg.aIccPrevFrameIndex[gr];
+ }
+ }
+ else {
+ for (gr = 0; gr < NO_HI_RES_ICC_BINS; gr++) {
+ pBsData->aaIccIndex[pBsData->noEnv-1][gr] = 0;
+ }
+ }
+ }
+
+ /* Update previous frame index buffers */
+ for (gr = 0; gr < NO_HI_RES_IID_BINS; gr++) {
+ h_ps_d->specificTo.mpeg.aIidPrevFrameIndex[gr] =
+ pBsData->aaIidIndex[pBsData->noEnv-1][gr];
+ }
+ for (gr = 0; gr < NO_HI_RES_ICC_BINS; gr++) {
+ h_ps_d->specificTo.mpeg.aIccPrevFrameIndex[gr] =
+ pBsData->aaIccIndex[pBsData->noEnv-1][gr];
+ }
+
+ /* PS data from bitstream (if avail) was decoded now */
+ h_ps_d->bPsDataAvail[h_ps_d->processSlot] = ppt_none;
+
+ /* handling of env borders for FIX & VAR */
+ if (pBsData->bFrameClass == 0) {
+ /* FIX_BORDERS NoEnv=0,1,2,4 */
+ pBsData->aEnvStartStop[0] = 0;
+ for (env=1; env<pBsData->noEnv; env++) {
+ pBsData->aEnvStartStop[env] =
+ (env * h_ps_d->noSubSamples) / pBsData->noEnv;
+ }
+ pBsData->aEnvStartStop[pBsData->noEnv] = h_ps_d->noSubSamples;
+ /* 1024 (32 slots) env borders: 0, 8, 16, 24, 32 */
+ /* 960 (30 slots) env borders: 0, 7, 15, 22, 30 */
+ }
+ else { /* if (h_ps_d->bFrameClass == 0) */
+ /* VAR_BORDERS NoEnv=1,2,3,4 */
+ pBsData->aEnvStartStop[0] = 0;
+
+ /* handle case aEnvStartStop[noEnv]<noSubSample for VAR_BORDERS by
+ duplicating last PS parameters and incrementing noEnv */
+ if (pBsData->aEnvStartStop[pBsData->noEnv] < h_ps_d->noSubSamples) {
+ for (gr = 0; gr < NO_HI_RES_IID_BINS; gr++) {
+ pBsData->aaIidIndex[pBsData->noEnv][gr] =
+ pBsData->aaIidIndex[pBsData->noEnv-1][gr];
+ }
+ for (gr = 0; gr < NO_HI_RES_ICC_BINS; gr++) {
+ pBsData->aaIccIndex[pBsData->noEnv][gr] =
+ pBsData->aaIccIndex[pBsData->noEnv-1][gr];
+ }
+ pBsData->noEnv++;
+ pBsData->aEnvStartStop[pBsData->noEnv] = h_ps_d->noSubSamples;
+ }
+
+ /* enforce strictly monotonic increasing borders */
+ for (env=1; env<pBsData->noEnv; env++) {
+ UCHAR thr;
+ thr = (UCHAR)h_ps_d->noSubSamples - (pBsData->noEnv - env);
+ if (pBsData->aEnvStartStop[env] > thr) {
+ pBsData->aEnvStartStop[env] = thr;
+ }
+ else {
+ thr = pBsData->aEnvStartStop[env-1]+1;
+ if (pBsData->aEnvStartStop[env] < thr) {
+ pBsData->aEnvStartStop[env] = thr;
+ }
+ }
+ }
+ } /* if (h_ps_d->bFrameClass == 0) ... else */
+
+ /* copy data prior to possible 20<->34 in-place mapping */
+ for (env=0; env<pBsData->noEnv; env++) {
+ UCHAR i;
+ for (i=0; i<NO_HI_RES_IID_BINS; i++) {
+ h_ps_d->specificTo.mpeg.coef.aaIidIndexMapped[env][i] = pBsData->aaIidIndex[env][i];
+ }
+ for (i=0; i<NO_HI_RES_ICC_BINS; i++) {
+ h_ps_d->specificTo.mpeg.coef.aaIccIndexMapped[env][i] = pBsData->aaIccIndex[env][i];
+ }
+ }
+
+
+ /* MPEG baseline PS */
+ /* Baseline version of PS always uses the hybrid filter structure with 20 stereo bands. */
+ /* If ICC/IID parameters for 34 stereo bands are decoded they have to be mapped to 20 */
+ /* stereo bands. */
+ /* Additionaly the IPD/OPD parameters won't be used. */
+
+ for (env=0; env<pBsData->noEnv; env++) {
+ if (pBsData->freqResIid == 2)
+ map34IndexTo20 (h_ps_d->specificTo.mpeg.coef.aaIidIndexMapped[env], NO_HI_RES_IID_BINS);
+ if (pBsData->freqResIcc == 2)
+ map34IndexTo20 (h_ps_d->specificTo.mpeg.coef.aaIccIndexMapped[env], NO_HI_RES_ICC_BINS);
+
+ /* IPD/OPD is disabled in baseline version and thus was removed here */
+ }
+
+ return (1);
+}
+
+
+/***************************************************************************/
+/*!
+
+ \brief Reads parametric stereo data from bitstream
+
+ \return
+
+****************************************************************************/
+unsigned int
+ReadPsData (HANDLE_PS_DEC h_ps_d, /*!< handle to struct PS_DEC */
+ HANDLE_FDK_BITSTREAM hBitBuf, /*!< handle to struct BIT_BUF */
+ int nBitsLeft /*!< max number of bits available */
+ )
+{
+ MPEG_PS_BS_DATA *pBsData;
+
+ UCHAR gr, env;
+ SCHAR dtFlag;
+ INT startbits;
+ Huffman CurrentTable;
+ SCHAR bEnableHeader;
+
+ if (!h_ps_d)
+ return 0;
+
+ pBsData = &h_ps_d->bsData[h_ps_d->bsReadSlot].mpeg;
+
+ if (h_ps_d->bsReadSlot != h_ps_d->bsLastSlot) {
+ /* Copy last header data */
+ FDKmemcpy(pBsData, &h_ps_d->bsData[h_ps_d->bsLastSlot].mpeg, sizeof(MPEG_PS_BS_DATA));
+ }
+
+
+ startbits = (INT) FDKgetValidBits(hBitBuf);
+
+ bEnableHeader = (SCHAR) FDKreadBits (hBitBuf, 1);
+
+ /* Read header */
+ if (bEnableHeader) {
+ pBsData->bPsHeaderValid = 1;
+ pBsData->bEnableIid = (UCHAR) FDKreadBits (hBitBuf, 1);
+ if (pBsData->bEnableIid) {
+ pBsData->modeIid = (UCHAR) FDKreadBits (hBitBuf, 3);
+ }
+
+ pBsData->bEnableIcc = (UCHAR) FDKreadBits (hBitBuf, 1);
+ if (pBsData->bEnableIcc) {
+ pBsData->modeIcc = (UCHAR) FDKreadBits (hBitBuf, 3);
+ }
+
+ pBsData->bEnableExt = (UCHAR) FDKreadBits (hBitBuf, 1);
+ }
+
+ pBsData->bFrameClass = (UCHAR) FDKreadBits (hBitBuf, 1);
+ if (pBsData->bFrameClass == 0) {
+ /* FIX_BORDERS NoEnv=0,1,2,4 */
+ pBsData->noEnv = FDK_sbrDecoder_aFixNoEnvDecode[(UCHAR) FDKreadBits (hBitBuf, 2)];
+ /* all additional handling of env borders is now in DecodePs() */
+ }
+ else {
+ /* VAR_BORDERS NoEnv=1,2,3,4 */
+ pBsData->noEnv = 1+(UCHAR) FDKreadBits (hBitBuf, 2);
+ for (env=1; env<pBsData->noEnv+1; env++)
+ pBsData->aEnvStartStop[env] = ((UCHAR) FDKreadBits (hBitBuf, 5)) + 1;
+ /* all additional handling of env borders is now in DecodePs() */
+ }
+
+ /* verify that IID & ICC modes (quant grid, freq res) are supported */
+ if ((pBsData->modeIid > 5) || (pBsData->modeIcc > 5)) {
+ /* no useful PS data could be read from bitstream */
+ h_ps_d->bPsDataAvail[h_ps_d->bsReadSlot] = ppt_none;
+ /* discard all remaining bits */
+ nBitsLeft -= startbits - FDKgetValidBits(hBitBuf);
+ while (nBitsLeft) {
+ int i = nBitsLeft;
+ if (i>8) {
+ i = 8;
+ }
+ FDKreadBits (hBitBuf, i);
+ nBitsLeft -= i;
+ }
+ return (startbits - FDKgetValidBits(hBitBuf));
+ }
+
+ if (pBsData->modeIid > 2){
+ pBsData->freqResIid = pBsData->modeIid-3;
+ pBsData->bFineIidQ = 1;
+ }
+ else{
+ pBsData->freqResIid = pBsData->modeIid;
+ pBsData->bFineIidQ = 0;
+ }
+
+ if (pBsData->modeIcc > 2){
+ pBsData->freqResIcc = pBsData->modeIcc-3;
+ }
+ else{
+ pBsData->freqResIcc = pBsData->modeIcc;
+ }
+
+
+ /* Extract IID data */
+ if (pBsData->bEnableIid) {
+ for (env=0; env<pBsData->noEnv; env++) {
+ dtFlag = (SCHAR)FDKreadBits (hBitBuf, 1);
+ if (!dtFlag)
+ {
+ if (pBsData->bFineIidQ)
+ CurrentTable = (Huffman)&aBookPsIidFineFreqDecode;
+ else
+ CurrentTable = (Huffman)&aBookPsIidFreqDecode;
+ }
+ else
+ {
+ if (pBsData->bFineIidQ)
+ CurrentTable = (Huffman)&aBookPsIidFineTimeDecode;
+ else
+ CurrentTable = (Huffman)&aBookPsIidTimeDecode;
+ }
+
+ for (gr = 0; gr < FDK_sbrDecoder_aNoIidBins[pBsData->freqResIid]; gr++)
+ pBsData->aaIidIndex[env][gr] = decode_huff_cw(CurrentTable,hBitBuf,NULL);
+ pBsData->abIidDtFlag[env] = dtFlag;
+ }
+ }
+
+ /* Extract ICC data */
+ if (pBsData->bEnableIcc) {
+ for (env=0; env<pBsData->noEnv; env++) {
+ dtFlag = (SCHAR)FDKreadBits (hBitBuf, 1);
+ if (!dtFlag)
+ CurrentTable = (Huffman)&aBookPsIccFreqDecode;
+ else
+ CurrentTable = (Huffman)&aBookPsIccTimeDecode;
+
+ for (gr = 0; gr < FDK_sbrDecoder_aNoIccBins[pBsData->freqResIcc]; gr++)
+ pBsData->aaIccIndex[env][gr] = decode_huff_cw(CurrentTable,hBitBuf,NULL);
+ pBsData->abIccDtFlag[env] = dtFlag;
+ }
+ }
+
+ if (pBsData->bEnableExt) {
+
+ /*!
+ Decoders that support only the baseline version of the PS tool are allowed
+ to ignore the IPD/OPD data, but according header data has to be parsed.
+ ISO/IEC 14496-3 Subpart 8 Annex 4
+ */
+
+ int cnt = FDKreadBits(hBitBuf, PS_EXTENSION_SIZE_BITS);
+ if (cnt == (1<<PS_EXTENSION_SIZE_BITS)-1) {
+ cnt += FDKreadBits(hBitBuf, PS_EXTENSION_ESC_COUNT_BITS);
+ }
+ while (cnt--)
+ FDKreadBits(hBitBuf, 8);
+ }
+
+
+ /* new PS data was read from bitstream */
+ h_ps_d->bPsDataAvail[h_ps_d->bsReadSlot] = ppt_mpeg;
+
+
+
+ return (startbits - FDKgetValidBits(hBitBuf));
+}
+