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1 /* -----------------------------------------------------------------------------
2 Software License for The Fraunhofer FDK AAC Codec Library for Android
3 
4 © Copyright  1995 - 2018 Fraunhofer-Gesellschaft zur Förderung der angewandten
5 Forschung e.V. All rights reserved.
6 
7  1.    INTRODUCTION
8 The Fraunhofer FDK AAC Codec Library for Android ("FDK AAC Codec") is software
9 that implements the MPEG Advanced Audio Coding ("AAC") encoding and decoding
10 scheme for digital audio. This FDK AAC Codec software is intended to be used on
11 a wide variety of Android devices.
12 
13 AAC's HE-AAC and HE-AAC v2 versions are regarded as today's most efficient
14 general perceptual audio codecs. AAC-ELD is considered the best-performing
15 full-bandwidth communications codec by independent studies and is widely
16 deployed. AAC has been standardized by ISO and IEC as part of the MPEG
17 specifications.
18 
19 Patent licenses for necessary patent claims for the FDK AAC Codec (including
20 those of Fraunhofer) may be obtained through Via Licensing
21 (www.vialicensing.com) or through the respective patent owners individually for
22 the purpose of encoding or decoding bit streams in products that are compliant
23 with the ISO/IEC MPEG audio standards. Please note that most manufacturers of
24 Android devices already license these patent claims through Via Licensing or
25 directly from the patent owners, and therefore FDK AAC Codec software may
26 already be covered under those patent licenses when it is used for those
27 licensed purposes only.
28 
29 Commercially-licensed AAC software libraries, including floating-point versions
30 with enhanced sound quality, are also available from Fraunhofer. Users are
31 encouraged to check the Fraunhofer website for additional applications
32 information and documentation.
33 
34 2.    COPYRIGHT LICENSE
35 
36 Redistribution and use in source and binary forms, with or without modification,
37 are permitted without payment of copyright license fees provided that you
38 satisfy the following conditions:
39 
40 You must retain the complete text of this software license in redistributions of
41 the FDK AAC Codec or your modifications thereto in source code form.
42 
43 You must retain the complete text of this software license in the documentation
44 and/or other materials provided with redistributions of the FDK AAC Codec or
45 your modifications thereto in binary form. You must make available free of
46 charge copies of the complete source code of the FDK AAC Codec and your
47 modifications thereto to recipients of copies in binary form.
48 
49 The name of Fraunhofer may not be used to endorse or promote products derived
50 from this library without prior written permission.
51 
52 You may not charge copyright license fees for anyone to use, copy or distribute
53 the FDK AAC Codec software or your modifications thereto.
54 
55 Your modified versions of the FDK AAC Codec must carry prominent notices stating
56 that you changed the software and the date of any change. For modified versions
57 of the FDK AAC Codec, the term "Fraunhofer FDK AAC Codec Library for Android"
58 must be replaced by the term "Third-Party Modified Version of the Fraunhofer FDK
59 AAC Codec Library for Android."
60 
61 3.    NO PATENT LICENSE
62 
63 NO EXPRESS OR IMPLIED LICENSES TO ANY PATENT CLAIMS, including without
64 limitation the patents of Fraunhofer, ARE GRANTED BY THIS SOFTWARE LICENSE.
65 Fraunhofer provides no warranty of patent non-infringement with respect to this
66 software.
67 
68 You may use this FDK AAC Codec software or modifications thereto only for
69 purposes that are authorized by appropriate patent licenses.
70 
71 4.    DISCLAIMER
72 
73 This FDK AAC Codec software is provided by Fraunhofer on behalf of the copyright
74 holders and contributors "AS IS" and WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES,
75 including but not limited to the implied warranties of merchantability and
76 fitness for a particular purpose. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
77 CONTRIBUTORS BE LIABLE for any direct, indirect, incidental, special, exemplary,
78 or consequential damages, including but not limited to procurement of substitute
79 goods or services; loss of use, data, or profits, or business interruption,
80 however caused and on any theory of liability, whether in contract, strict
81 liability, or tort (including negligence), arising in any way out of the use of
82 this software, even if advised of the possibility of such damage.
83 
84 5.    CONTACT INFORMATION
85 
86 Fraunhofer Institute for Integrated Circuits IIS
87 Attention: Audio and Multimedia Departments - FDK AAC LL
88 Am Wolfsmantel 33
89 91058 Erlangen, Germany
90 
91 www.iis.fraunhofer.de/amm
92 amm-info@iis.fraunhofer.de
93 ----------------------------------------------------------------------------- */
94 
95 /**************************** SBR decoder library ******************************
96 
97    Author(s):
98 
99    Description:
100 
101 *******************************************************************************/
102 
103 #include "psbitdec.h"
104 
105 #include "sbr_rom.h"
106 #include "huff_dec.h"
107 
108 /* PS dec privat functions */
109 SBR_ERROR ResetPsDec(HANDLE_PS_DEC h_ps_d);
110 
111 /***************************************************************************/
112 /*!
113   \brief  huffman decoding by codebook table
114 
115   \return index of huffman codebook table
116 
117 ****************************************************************************/
decode_huff_cw(Huffman h,HANDLE_FDK_BITSTREAM hBitBuf,int * length)118 static SCHAR decode_huff_cw(
119     Huffman h,                    /*!< pointer to huffman codebook table */
120     HANDLE_FDK_BITSTREAM hBitBuf, /*!< Handle to Bitbuffer */
121     int *length)                  /*!< length of huffman codeword (or NULL) */
122 {
123   UCHAR bit = 0;
124   SCHAR index = 0;
125   UCHAR bitCount = 0;
126 
127   while (index >= 0) {
128     bit = FDKreadBits(hBitBuf, 1);
129     bitCount++;
130     index = h[index][bit];
131   }
132   if (length) {
133     *length = bitCount;
134   }
135   return (index + 64); /* Add offset */
136 }
137 
138 /***************************************************************************/
139 /*!
140   \brief  helper function - limiting of value to min/max values
141 
142   \return limited value
143 
144 ****************************************************************************/
145 
limitMinMax(SCHAR i,SCHAR min,SCHAR max)146 static SCHAR limitMinMax(SCHAR i, SCHAR min, SCHAR max) {
147   if (i < min)
148     return min;
149   else if (i > max)
150     return max;
151   else
152     return i;
153 }
154 
155 /***************************************************************************/
156 /*!
157   \brief  Decodes delta values in-place and updates
158           data buffers according to quantization classes.
159 
160   When delta coded in frequency the first element is deltacode from zero.
161   aIndex buffer is decoded from delta values to actual values.
162 
163   \return none
164 
165 ****************************************************************************/
deltaDecodeArray(SCHAR enable,SCHAR * aIndex,SCHAR * aPrevFrameIndex,SCHAR DtDf,UCHAR nrElements,UCHAR stride,SCHAR minIdx,SCHAR maxIdx)166 static void deltaDecodeArray(
167     SCHAR enable, SCHAR *aIndex,  /*!< ICC/IID parameters */
168     SCHAR *aPrevFrameIndex,       /*!< ICC/IID parameters  of previous frame */
169     SCHAR DtDf, UCHAR nrElements, /*!< as conveyed in bitstream */
170                                   /*!< output array size: nrElements*stride */
171     UCHAR stride,                 /*!< 1=dflt, 2=half freq. resolution */
172     SCHAR minIdx, SCHAR maxIdx) {
173   int i;
174 
175   /* Delta decode */
176   if (enable == 1) {
177     if (DtDf == 0) { /* Delta coded in freq */
178       aIndex[0] = 0 + aIndex[0];
179       aIndex[0] = limitMinMax(aIndex[0], minIdx, maxIdx);
180       for (i = 1; i < nrElements; i++) {
181         aIndex[i] = aIndex[i - 1] + aIndex[i];
182         aIndex[i] = limitMinMax(aIndex[i], minIdx, maxIdx);
183       }
184     } else { /* Delta time */
185       for (i = 0; i < nrElements; i++) {
186         aIndex[i] = aPrevFrameIndex[i * stride] + aIndex[i];
187         aIndex[i] = limitMinMax(aIndex[i], minIdx, maxIdx);
188       }
189     }
190   } else { /* No data is sent, set index to zero */
191     for (i = 0; i < nrElements; i++) {
192       aIndex[i] = 0;
193     }
194   }
195   if (stride == 2) {
196     for (i = nrElements * stride - 1; i > 0; i--) {
197       aIndex[i] = aIndex[i >> 1];
198     }
199   }
200 }
201 
202 /***************************************************************************/
203 /*!
204   \brief Mapping of ICC/IID parameters to 20 stereo bands
205 
206   \return none
207 
208 ****************************************************************************/
map34IndexTo20(SCHAR * aIndex,UCHAR noBins)209 static void map34IndexTo20(SCHAR *aIndex, /*!< decoded ICC/IID parameters */
210                            UCHAR noBins)  /*!< number of stereo bands     */
211 {
212   aIndex[0] = (2 * aIndex[0] + aIndex[1]) / 3;
213   aIndex[1] = (aIndex[1] + 2 * aIndex[2]) / 3;
214   aIndex[2] = (2 * aIndex[3] + aIndex[4]) / 3;
215   aIndex[3] = (aIndex[4] + 2 * aIndex[5]) / 3;
216   aIndex[4] = (aIndex[6] + aIndex[7]) / 2;
217   aIndex[5] = (aIndex[8] + aIndex[9]) / 2;
218   aIndex[6] = aIndex[10];
219   aIndex[7] = aIndex[11];
220   aIndex[8] = (aIndex[12] + aIndex[13]) / 2;
221   aIndex[9] = (aIndex[14] + aIndex[15]) / 2;
222   aIndex[10] = aIndex[16];
223   /* For IPD/OPD it stops here */
224 
225   if (noBins == NO_HI_RES_BINS) {
226     aIndex[11] = aIndex[17];
227     aIndex[12] = aIndex[18];
228     aIndex[13] = aIndex[19];
229     aIndex[14] = (aIndex[20] + aIndex[21]) / 2;
230     aIndex[15] = (aIndex[22] + aIndex[23]) / 2;
231     aIndex[16] = (aIndex[24] + aIndex[25]) / 2;
232     aIndex[17] = (aIndex[26] + aIndex[27]) / 2;
233     aIndex[18] = (aIndex[28] + aIndex[29] + aIndex[30] + aIndex[31]) / 4;
234     aIndex[19] = (aIndex[32] + aIndex[33]) / 2;
235   }
236 }
237 
238 /***************************************************************************/
239 /*!
240   \brief  Decodes delta coded IID, ICC, IPD and OPD indices
241 
242   \return PS processing flag. If set to 1
243 
244 ****************************************************************************/
DecodePs(struct PS_DEC * h_ps_d,const UCHAR frameError,PS_DEC_COEFFICIENTS * pScratch)245 int DecodePs(struct PS_DEC *h_ps_d,  /*!< PS handle */
246              const UCHAR frameError, /*!< Flag telling that frame had errors */
247              PS_DEC_COEFFICIENTS *pScratch) {
248   MPEG_PS_BS_DATA *pBsData;
249   UCHAR gr, env;
250   int bPsHeaderValid, bPsDataAvail;
251 
252   /* Assign Scratch */
253   h_ps_d->specificTo.mpeg.pCoef = pScratch;
254 
255   /* Shortcuts to avoid deferencing and keep the code readable */
256   pBsData = &h_ps_d->bsData[h_ps_d->processSlot].mpeg;
257   bPsHeaderValid = pBsData->bPsHeaderValid;
258   bPsDataAvail =
259       (h_ps_d->bPsDataAvail[h_ps_d->processSlot] == ppt_mpeg) ? 1 : 0;
260 
261   /***************************************************************************************
262    * Decide whether to process or to conceal PS data or not. */
263 
264   if ((h_ps_d->psDecodedPrv && !frameError && !bPsDataAvail) ||
265       (!h_ps_d->psDecodedPrv &&
266        (frameError || !bPsDataAvail || !bPsHeaderValid))) {
267     /* Don't apply PS processing.
268      * Declare current PS header and bitstream data invalid. */
269     pBsData->bPsHeaderValid = 0;
270     h_ps_d->bPsDataAvail[h_ps_d->processSlot] = ppt_none;
271     return (0);
272   }
273 
274   if (frameError ||
275       !bPsHeaderValid) { /* no new PS data available (e.g. frame loss) */
276     /* => keep latest data constant (i.e. FIX with noEnv=0) */
277     pBsData->noEnv = 0;
278   }
279 
280   /***************************************************************************************
281    * Decode bitstream payload or prepare parameter for concealment:
282    */
283   for (env = 0; env < pBsData->noEnv; env++) {
284     SCHAR *aPrevIidIndex;
285     SCHAR *aPrevIccIndex;
286 
287     UCHAR noIidSteps = pBsData->bFineIidQ ? NO_IID_STEPS_FINE : NO_IID_STEPS;
288 
289     if (env == 0) {
290       aPrevIidIndex = h_ps_d->specificTo.mpeg.aIidPrevFrameIndex;
291       aPrevIccIndex = h_ps_d->specificTo.mpeg.aIccPrevFrameIndex;
292     } else {
293       aPrevIidIndex = pBsData->aaIidIndex[env - 1];
294       aPrevIccIndex = pBsData->aaIccIndex[env - 1];
295     }
296 
297     deltaDecodeArray(pBsData->bEnableIid, pBsData->aaIidIndex[env],
298                      aPrevIidIndex, pBsData->abIidDtFlag[env],
299                      FDK_sbrDecoder_aNoIidBins[pBsData->freqResIid],
300                      (pBsData->freqResIid) ? 1 : 2, -noIidSteps, noIidSteps);
301 
302     deltaDecodeArray(pBsData->bEnableIcc, pBsData->aaIccIndex[env],
303                      aPrevIccIndex, pBsData->abIccDtFlag[env],
304                      FDK_sbrDecoder_aNoIccBins[pBsData->freqResIcc],
305                      (pBsData->freqResIcc) ? 1 : 2, 0, NO_ICC_STEPS - 1);
306   } /* for (env=0; env<pBsData->noEnv; env++) */
307 
308   /* handling of FIX noEnv=0 */
309   if (pBsData->noEnv == 0) {
310     /* set noEnv=1, keep last parameters or force 0 if not enabled */
311     pBsData->noEnv = 1;
312 
313     if (pBsData->bEnableIid) {
314       pBsData->bFineIidQ = h_ps_d->specificTo.mpeg.bPrevFrameFineIidQ;
315       pBsData->freqResIid = h_ps_d->specificTo.mpeg.prevFreqResIid;
316       for (gr = 0; gr < NO_HI_RES_IID_BINS; gr++) {
317         pBsData->aaIidIndex[pBsData->noEnv - 1][gr] =
318             h_ps_d->specificTo.mpeg.aIidPrevFrameIndex[gr];
319       }
320     } else {
321       for (gr = 0; gr < NO_HI_RES_IID_BINS; gr++) {
322         pBsData->aaIidIndex[pBsData->noEnv - 1][gr] = 0;
323       }
324     }
325 
326     if (pBsData->bEnableIcc) {
327       pBsData->freqResIcc = h_ps_d->specificTo.mpeg.prevFreqResIcc;
328       for (gr = 0; gr < NO_HI_RES_ICC_BINS; gr++) {
329         pBsData->aaIccIndex[pBsData->noEnv - 1][gr] =
330             h_ps_d->specificTo.mpeg.aIccPrevFrameIndex[gr];
331       }
332     } else {
333       for (gr = 0; gr < NO_HI_RES_ICC_BINS; gr++) {
334         pBsData->aaIccIndex[pBsData->noEnv - 1][gr] = 0;
335       }
336     }
337   }
338 
339   /* Update previous frame Iid quantization */
340   h_ps_d->specificTo.mpeg.bPrevFrameFineIidQ = pBsData->bFineIidQ;
341 
342   /* Update previous frequency resolution for IID */
343   h_ps_d->specificTo.mpeg.prevFreqResIid = pBsData->freqResIid;
344 
345   /* Update previous frequency resolution for ICC */
346   h_ps_d->specificTo.mpeg.prevFreqResIcc = pBsData->freqResIcc;
347 
348   /* Update previous frame index buffers */
349   for (gr = 0; gr < NO_HI_RES_IID_BINS; gr++) {
350     h_ps_d->specificTo.mpeg.aIidPrevFrameIndex[gr] =
351         pBsData->aaIidIndex[pBsData->noEnv - 1][gr];
352   }
353   for (gr = 0; gr < NO_HI_RES_ICC_BINS; gr++) {
354     h_ps_d->specificTo.mpeg.aIccPrevFrameIndex[gr] =
355         pBsData->aaIccIndex[pBsData->noEnv - 1][gr];
356   }
357 
358   /* PS data from bitstream (if avail) was decoded now */
359   h_ps_d->bPsDataAvail[h_ps_d->processSlot] = ppt_none;
360 
361   /* handling of env borders for FIX & VAR */
362   if (pBsData->bFrameClass == 0) {
363     /* FIX_BORDERS NoEnv=0,1,2,4 */
364     pBsData->aEnvStartStop[0] = 0;
365     for (env = 1; env < pBsData->noEnv; env++) {
366       pBsData->aEnvStartStop[env] =
367           (env * h_ps_d->noSubSamples) / pBsData->noEnv;
368     }
369     pBsData->aEnvStartStop[pBsData->noEnv] = h_ps_d->noSubSamples;
370     /* 1024 (32 slots) env borders:  0, 8, 16, 24, 32 */
371     /*  960 (30 slots) env borders:  0, 7, 15, 22, 30 */
372   } else { /* if (h_ps_d->bFrameClass == 0) */
373     /* VAR_BORDERS NoEnv=1,2,3,4 */
374     pBsData->aEnvStartStop[0] = 0;
375 
376     /* handle case aEnvStartStop[noEnv]<noSubSample for VAR_BORDERS by
377        duplicating last PS parameters and incrementing noEnv */
378     if (pBsData->aEnvStartStop[pBsData->noEnv] < h_ps_d->noSubSamples) {
379       for (gr = 0; gr < NO_HI_RES_IID_BINS; gr++) {
380         pBsData->aaIidIndex[pBsData->noEnv][gr] =
381             pBsData->aaIidIndex[pBsData->noEnv - 1][gr];
382       }
383       for (gr = 0; gr < NO_HI_RES_ICC_BINS; gr++) {
384         pBsData->aaIccIndex[pBsData->noEnv][gr] =
385             pBsData->aaIccIndex[pBsData->noEnv - 1][gr];
386       }
387       pBsData->noEnv++;
388       pBsData->aEnvStartStop[pBsData->noEnv] = h_ps_d->noSubSamples;
389     }
390 
391     /* enforce strictly monotonic increasing borders */
392     for (env = 1; env < pBsData->noEnv; env++) {
393       UCHAR thr;
394       thr = (UCHAR)h_ps_d->noSubSamples - (pBsData->noEnv - env);
395       if (pBsData->aEnvStartStop[env] > thr) {
396         pBsData->aEnvStartStop[env] = thr;
397       } else {
398         thr = pBsData->aEnvStartStop[env - 1] + 1;
399         if (pBsData->aEnvStartStop[env] < thr) {
400           pBsData->aEnvStartStop[env] = thr;
401         }
402       }
403     }
404   } /* if (h_ps_d->bFrameClass == 0) ... else */
405 
406   /* copy data prior to possible 20<->34 in-place mapping */
407   for (env = 0; env < pBsData->noEnv; env++) {
408     UCHAR i;
409     for (i = 0; i < NO_HI_RES_IID_BINS; i++) {
410       h_ps_d->specificTo.mpeg.pCoef->aaIidIndexMapped[env][i] =
411           pBsData->aaIidIndex[env][i];
412     }
413     for (i = 0; i < NO_HI_RES_ICC_BINS; i++) {
414       h_ps_d->specificTo.mpeg.pCoef->aaIccIndexMapped[env][i] =
415           pBsData->aaIccIndex[env][i];
416     }
417   }
418 
419   /* MPEG baseline PS */
420   /* Baseline version of PS always uses the hybrid filter structure with 20
421    * stereo bands. */
422   /* If ICC/IID parameters for 34 stereo bands are decoded they have to be
423    * mapped to 20   */
424   /* stereo bands. */
425   /* Additionaly the IPD/OPD parameters won't be used. */
426 
427   for (env = 0; env < pBsData->noEnv; env++) {
428     if (pBsData->freqResIid == 2)
429       map34IndexTo20(h_ps_d->specificTo.mpeg.pCoef->aaIidIndexMapped[env],
430                      NO_HI_RES_IID_BINS);
431     if (pBsData->freqResIcc == 2)
432       map34IndexTo20(h_ps_d->specificTo.mpeg.pCoef->aaIccIndexMapped[env],
433                      NO_HI_RES_ICC_BINS);
434 
435     /* IPD/OPD is disabled in baseline version and thus was removed here */
436   }
437 
438   return (1);
439 }
440 
441 /***************************************************************************/
442 /*!
443 
444   \brief  Reads parametric stereo data from bitstream
445 
446   \return
447 
448 ****************************************************************************/
ReadPsData(HANDLE_PS_DEC h_ps_d,HANDLE_FDK_BITSTREAM hBitBuf,int nBitsLeft)449 unsigned int ReadPsData(
450     HANDLE_PS_DEC h_ps_d,         /*!< handle to struct PS_DEC */
451     HANDLE_FDK_BITSTREAM hBitBuf, /*!< handle to struct BIT_BUF */
452     int nBitsLeft                 /*!< max number of bits available */
453 ) {
454   MPEG_PS_BS_DATA *pBsData;
455 
456   UCHAR gr, env;
457   SCHAR dtFlag;
458   INT startbits;
459   Huffman CurrentTable;
460   SCHAR bEnableHeader;
461 
462   if (!h_ps_d) return 0;
463 
464   pBsData = &h_ps_d->bsData[h_ps_d->bsReadSlot].mpeg;
465 
466   if (h_ps_d->bsReadSlot != h_ps_d->bsLastSlot) {
467     /* Copy last header data */
468     FDKmemcpy(pBsData, &h_ps_d->bsData[h_ps_d->bsLastSlot].mpeg,
469               sizeof(MPEG_PS_BS_DATA));
470   }
471 
472   startbits = (INT)FDKgetValidBits(hBitBuf);
473 
474   bEnableHeader = (SCHAR)FDKreadBits(hBitBuf, 1);
475 
476   /* Read header */
477   if (bEnableHeader) {
478     pBsData->bPsHeaderValid = 1;
479     pBsData->bEnableIid = (UCHAR)FDKreadBits(hBitBuf, 1);
480     if (pBsData->bEnableIid) {
481       pBsData->modeIid = (UCHAR)FDKreadBits(hBitBuf, 3);
482     }
483 
484     pBsData->bEnableIcc = (UCHAR)FDKreadBits(hBitBuf, 1);
485     if (pBsData->bEnableIcc) {
486       pBsData->modeIcc = (UCHAR)FDKreadBits(hBitBuf, 3);
487     }
488 
489     pBsData->bEnableExt = (UCHAR)FDKreadBits(hBitBuf, 1);
490   }
491 
492   pBsData->bFrameClass = (UCHAR)FDKreadBits(hBitBuf, 1);
493   if (pBsData->bFrameClass == 0) {
494     /* FIX_BORDERS NoEnv=0,1,2,4 */
495     pBsData->noEnv =
496         FDK_sbrDecoder_aFixNoEnvDecode[(UCHAR)FDKreadBits(hBitBuf, 2)];
497     /* all additional handling of env borders is now in DecodePs() */
498   } else {
499     /* VAR_BORDERS NoEnv=1,2,3,4 */
500     pBsData->noEnv = 1 + (UCHAR)FDKreadBits(hBitBuf, 2);
501     for (env = 1; env < pBsData->noEnv + 1; env++)
502       pBsData->aEnvStartStop[env] = ((UCHAR)FDKreadBits(hBitBuf, 5)) + 1;
503     /* all additional handling of env borders is now in DecodePs() */
504   }
505 
506   /* verify that IID & ICC modes (quant grid, freq res) are supported */
507   if ((pBsData->modeIid > 5) || (pBsData->modeIcc > 5)) {
508     /* no useful PS data could be read from bitstream */
509     h_ps_d->bPsDataAvail[h_ps_d->bsReadSlot] = ppt_none;
510     /* discard all remaining bits */
511     nBitsLeft -= startbits - (INT)FDKgetValidBits(hBitBuf);
512     while (nBitsLeft > 0) {
513       int i = nBitsLeft;
514       if (i > 8) {
515         i = 8;
516       }
517       FDKreadBits(hBitBuf, i);
518       nBitsLeft -= i;
519     }
520     return (UINT)(startbits - (INT)FDKgetValidBits(hBitBuf));
521   }
522 
523   if (pBsData->modeIid > 2) {
524     pBsData->freqResIid = pBsData->modeIid - 3;
525     pBsData->bFineIidQ = 1;
526   } else {
527     pBsData->freqResIid = pBsData->modeIid;
528     pBsData->bFineIidQ = 0;
529   }
530 
531   if (pBsData->modeIcc > 2) {
532     pBsData->freqResIcc = pBsData->modeIcc - 3;
533   } else {
534     pBsData->freqResIcc = pBsData->modeIcc;
535   }
536 
537   /* Extract IID data */
538   if (pBsData->bEnableIid) {
539     for (env = 0; env < pBsData->noEnv; env++) {
540       dtFlag = (SCHAR)FDKreadBits(hBitBuf, 1);
541       if (!dtFlag) {
542         if (pBsData->bFineIidQ)
543           CurrentTable = (Huffman)&aBookPsIidFineFreqDecode;
544         else
545           CurrentTable = (Huffman)&aBookPsIidFreqDecode;
546       } else {
547         if (pBsData->bFineIidQ)
548           CurrentTable = (Huffman)&aBookPsIidFineTimeDecode;
549         else
550           CurrentTable = (Huffman)&aBookPsIidTimeDecode;
551       }
552 
553       for (gr = 0; gr < FDK_sbrDecoder_aNoIidBins[pBsData->freqResIid]; gr++)
554         pBsData->aaIidIndex[env][gr] =
555             decode_huff_cw(CurrentTable, hBitBuf, NULL);
556       pBsData->abIidDtFlag[env] = dtFlag;
557     }
558   }
559 
560   /* Extract ICC data */
561   if (pBsData->bEnableIcc) {
562     for (env = 0; env < pBsData->noEnv; env++) {
563       dtFlag = (SCHAR)FDKreadBits(hBitBuf, 1);
564       if (!dtFlag)
565         CurrentTable = (Huffman)&aBookPsIccFreqDecode;
566       else
567         CurrentTable = (Huffman)&aBookPsIccTimeDecode;
568 
569       for (gr = 0; gr < FDK_sbrDecoder_aNoIccBins[pBsData->freqResIcc]; gr++)
570         pBsData->aaIccIndex[env][gr] =
571             decode_huff_cw(CurrentTable, hBitBuf, NULL);
572       pBsData->abIccDtFlag[env] = dtFlag;
573     }
574   }
575 
576   if (pBsData->bEnableExt) {
577     /*!
578     Decoders that support only the baseline version of the PS tool are allowed
579     to ignore the IPD/OPD data, but according header data has to be parsed.
580     ISO/IEC 14496-3 Subpart 8 Annex 4
581     */
582 
583     int cnt = FDKreadBits(hBitBuf, PS_EXTENSION_SIZE_BITS);
584     if (cnt == (1 << PS_EXTENSION_SIZE_BITS) - 1) {
585       cnt += FDKreadBits(hBitBuf, PS_EXTENSION_ESC_COUNT_BITS);
586     }
587     while (cnt--) FDKreadBits(hBitBuf, 8);
588   }
589 
590   /* new PS data was read from bitstream */
591   h_ps_d->bPsDataAvail[h_ps_d->bsReadSlot] = ppt_mpeg;
592 
593   return (startbits - (INT)FDKgetValidBits(hBitBuf));
594 }
595