1 
2 /* -----------------------------------------------------------------------------------------------------------
3 Software License for The Fraunhofer FDK AAC Codec Library for Android
4 
5 � Copyright  1995 - 2015 Fraunhofer-Gesellschaft zur F�rderung der angewandten Forschung e.V.
6   All rights reserved.
7 
8  1.    INTRODUCTION
9 The Fraunhofer FDK AAC Codec Library for Android ("FDK AAC Codec") is software that implements
10 the MPEG Advanced Audio Coding ("AAC") encoding and decoding scheme for digital audio.
11 This FDK AAC Codec software is intended to be used on a wide variety of Android devices.
12 
13 AAC's HE-AAC and HE-AAC v2 versions are regarded as today's most efficient general perceptual
14 audio codecs. AAC-ELD is considered the best-performing full-bandwidth communications codec by
15 independent studies and is widely deployed. AAC has been standardized by ISO and IEC as part
16 of the MPEG specifications.
17 
18 Patent licenses for necessary patent claims for the FDK AAC Codec (including those of Fraunhofer)
19 may be obtained through Via Licensing (www.vialicensing.com) or through the respective patent owners
20 individually for the purpose of encoding or decoding bit streams in products that are compliant with
21 the ISO/IEC MPEG audio standards. Please note that most manufacturers of Android devices already license
22 these patent claims through Via Licensing or directly from the patent owners, and therefore FDK AAC Codec
23 software may already be covered under those patent licenses when it is used for those licensed purposes only.
24 
25 Commercially-licensed AAC software libraries, including floating-point versions with enhanced sound quality,
26 are also available from Fraunhofer. Users are encouraged to check the Fraunhofer website for additional
27 applications information and documentation.
28 
29 2.    COPYRIGHT LICENSE
30 
31 Redistribution and use in source and binary forms, with or without modification, are permitted without
32 payment of copyright license fees provided that you satisfy the following conditions:
33 
34 You must retain the complete text of this software license in redistributions of the FDK AAC Codec or
35 your modifications thereto in source code form.
36 
37 You must retain the complete text of this software license in the documentation and/or other materials
38 provided with redistributions of the FDK AAC Codec or your modifications thereto in binary form.
39 You must make available free of charge copies of the complete source code of the FDK AAC Codec and your
40 modifications thereto to recipients of copies in binary form.
41 
42 The name of Fraunhofer may not be used to endorse or promote products derived from this library without
43 prior written permission.
44 
45 You may not charge copyright license fees for anyone to use, copy or distribute the FDK AAC Codec
46 software or your modifications thereto.
47 
48 Your modified versions of the FDK AAC Codec must carry prominent notices stating that you changed the software
49 and the date of any change. For modified versions of the FDK AAC Codec, the term
50 "Fraunhofer FDK AAC Codec Library for Android" must be replaced by the term
51 "Third-Party Modified Version of the Fraunhofer FDK AAC Codec Library for Android."
52 
53 3.    NO PATENT LICENSE
54 
55 NO EXPRESS OR IMPLIED LICENSES TO ANY PATENT CLAIMS, including without limitation the patents of Fraunhofer,
56 ARE GRANTED BY THIS SOFTWARE LICENSE. Fraunhofer provides no warranty of patent non-infringement with
57 respect to this software.
58 
59 You may use this FDK AAC Codec software or modifications thereto only for purposes that are authorized
60 by appropriate patent licenses.
61 
62 4.    DISCLAIMER
63 
64 This FDK AAC Codec software is provided by Fraunhofer on behalf of the copyright holders and contributors
65 "AS IS" and WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, including but not limited to the implied warranties
66 of merchantability and fitness for a particular purpose. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
67 CONTRIBUTORS BE LIABLE for any direct, indirect, incidental, special, exemplary, or consequential damages,
68 including but not limited to procurement of substitute goods or services; loss of use, data, or profits,
69 or business interruption, however caused and on any theory of liability, whether in contract, strict
70 liability, or tort (including negligence), arising in any way out of the use of this software, even if
71 advised of the possibility of such damage.
72 
73 5.    CONTACT INFORMATION
74 
75 Fraunhofer Institute for Integrated Circuits IIS
76 Attention: Audio and Multimedia Departments - FDK AAC LL
77 Am Wolfsmantel 33
78 91058 Erlangen, Germany
79 
80 www.iis.fraunhofer.de/amm
81 amm-info@iis.fraunhofer.de
82 ----------------------------------------------------------------------------------------------------------- */
83 
84 /*!
85   \file
86   \brief  Envelope extraction
87   The functions provided by this module are mostly called by applySBR(). After it is
88   determined that there is valid SBR data, sbrGetHeaderData() might be called if the current
89   SBR data contains an \ref SBR_HEADER_ELEMENT as opposed to a \ref SBR_STANDARD_ELEMENT. This function
90   may return various error codes as defined in #SBR_HEADER_STATUS . Most importantly it returns HEADER_RESET when decoder
91   settings need to be recalculated according to the SBR specifications. In that case applySBR()
92   will initiatite the required re-configuration.
93 
94   The header data is stored in a #SBR_HEADER_DATA structure.
95 
96   The actual SBR data for the current frame is decoded into SBR_FRAME_DATA stuctures by sbrGetChannelPairElement()
97   [for stereo streams] and sbrGetSingleChannelElement() [for mono streams]. There is no fractional arithmetic involved.
98 
99   Once the information is extracted, the data needs to be further prepared before the actual decoding process.
100   This is done in decodeSbrData().
101 
102   \sa Description of buffer management in applySBR(). \ref documentationOverview
103 
104   <h1>About the SBR data format:</h1>
105 
106   Each frame includes SBR data (side chain information), and can be either the \ref SBR_HEADER_ELEMENT or the \ref SBR_STANDARD_ELEMENT.
107   Parts of the data can be protected by a CRC checksum.
108 
109   \anchor SBR_HEADER_ELEMENT <h2>The SBR_HEADER_ELEMENT</h2>
110 
111   The SBR_HEADER_ELEMENT can be transmitted with every frame, however, it typically is send every second or so. It contains fundamental
112   information such as SBR sampling frequency and frequency range as well as control signals that do not require frequent changes. It also
113   includes the \ref SBR_STANDARD_ELEMENT.
114 
115   Depending on the changes between the information in a current SBR_HEADER_ELEMENT and the previous SBR_HEADER_ELEMENT, the SBR decoder might need
116   to be reset and reconfigured (e.g. new tables need to be calculated).
117 
118   \anchor SBR_STANDARD_ELEMENT <h2>The SBR_STANDARD_ELEMENT</h2>
119 
120   This data can be subdivided into "side info" and "raw data", where side info is defined as signals needed to decode the raw data
121   and some decoder tuning signals. Raw data is referred to as PCM and Huffman coded envelope and noise floor estimates. The side info also
122   includes information about the time-frequency grid for the current frame.
123 
124   \sa \ref documentationOverview
125 */
126 
127 #include "env_extr.h"
128 
129 #include "sbr_ram.h"
130 #include "sbr_rom.h"
131 #include "huff_dec.h"
132 
133 
134 #include "psbitdec.h"
135 
136 #define DRM_PARAMETRIC_STEREO   0
137 #define EXTENSION_ID_PS_CODING  2
138 
139 
140 static int extractFrameInfo (HANDLE_FDK_BITSTREAM   hBs,
141                              HANDLE_SBR_HEADER_DATA hHeaderData,
142                              HANDLE_SBR_FRAME_DATA  h_frame_data,
143                              const UINT             nrOfChannels,
144                              const UINT             flags
145                             );
146 
147 
148 static int sbrGetEnvelope (HANDLE_SBR_HEADER_DATA hHeaderData,
149                            HANDLE_SBR_FRAME_DATA  h_frame_data,
150                            HANDLE_FDK_BITSTREAM   hBs,
151                            const UINT flags);
152 
153 static void sbrGetDirectionControlData (HANDLE_SBR_FRAME_DATA hFrameData,
154                                         HANDLE_FDK_BITSTREAM hBs);
155 
156 static void sbrGetNoiseFloorData (HANDLE_SBR_HEADER_DATA hHeaderData,
157                                   HANDLE_SBR_FRAME_DATA  h_frame_data,
158                                   HANDLE_FDK_BITSTREAM   hBs);
159 
160 static int checkFrameInfo (FRAME_INFO *pFrameInfo, int numberOfTimeSlots, int overlap, int timeStep);
161 
162 SBR_ERROR
initHeaderData(HANDLE_SBR_HEADER_DATA hHeaderData,const int sampleRateIn,const int sampleRateOut,const int samplesPerFrame,const UINT flags)163 initHeaderData (
164         HANDLE_SBR_HEADER_DATA  hHeaderData,
165         const int               sampleRateIn,
166         const int               sampleRateOut,
167         const int               samplesPerFrame,
168         const UINT              flags
169         )
170 {
171   HANDLE_FREQ_BAND_DATA hFreq = &hHeaderData->freqBandData;
172   SBR_ERROR sbrError = SBRDEC_OK;
173   int numAnalysisBands;
174 
175   if ( sampleRateIn == sampleRateOut ) {
176     hHeaderData->sbrProcSmplRate = sampleRateOut<<1;
177     numAnalysisBands = 32;
178   } else {
179     hHeaderData->sbrProcSmplRate = sampleRateOut;
180     if ( (sampleRateOut>>1) == sampleRateIn) {
181       /* 1:2 */
182       numAnalysisBands = 32;
183     } else if ( (sampleRateOut>>2) == sampleRateIn ) {
184       /* 1:4 */
185       numAnalysisBands = 32;
186     } else if ( (sampleRateOut*3)>>3 == (sampleRateIn*8)>>3 ) {
187       /* 3:8, 3/4 core frame length */
188       numAnalysisBands = 24;
189     } else {
190       sbrError = SBRDEC_UNSUPPORTED_CONFIG;
191       goto bail;
192     }
193   }
194 
195   /* Fill in default values first */
196   hHeaderData->syncState          = SBR_NOT_INITIALIZED;
197   hHeaderData->status             = 0;
198   hHeaderData->frameErrorFlag     = 0;
199 
200   hHeaderData->bs_info.ampResolution     = 1;
201   hHeaderData->bs_info.xover_band        = 0;
202   hHeaderData->bs_info.sbr_preprocessing = 0;
203 
204   hHeaderData->bs_data.startFreq       = 5;
205   hHeaderData->bs_data.stopFreq        = 0;
206   hHeaderData->bs_data.freqScale       = 2;
207   hHeaderData->bs_data.alterScale      = 1;
208   hHeaderData->bs_data.noise_bands     = 2;
209   hHeaderData->bs_data.limiterBands    = 2;
210   hHeaderData->bs_data.limiterGains    = 2;
211   hHeaderData->bs_data.interpolFreq    = 1;
212   hHeaderData->bs_data.smoothingLength = 1;
213 
214   hHeaderData->timeStep = (flags & SBRDEC_ELD_GRID) ? 1 : 2;
215 
216   /* Setup pointers to frequency band tables */
217   hFreq->freqBandTable[0]  = hFreq->freqBandTableLo;
218   hFreq->freqBandTable[1] = hFreq->freqBandTableHi;
219 
220   /* Patch some entries */
221   if (sampleRateOut > 24000) {    /* Trigger an error if SBR is going to be processed without     */
222     hHeaderData->bs_data.startFreq = 7;   /*   having read these frequency values from bit stream before. */
223     hHeaderData->bs_data.stopFreq  = 3;
224   }
225 
226   /* One SBR timeslot corresponds to the amount of samples equal to the amount of analysis bands, divided by the timestep. */
227   hHeaderData->numberTimeSlots = (samplesPerFrame/numAnalysisBands) >> (hHeaderData->timeStep - 1);
228   if (hHeaderData->numberTimeSlots > (16)) {
229     sbrError = SBRDEC_UNSUPPORTED_CONFIG;
230   }
231 
232   hHeaderData->numberOfAnalysisBands = numAnalysisBands;
233 
234 bail:
235   return sbrError;
236 }
237 
238 
239 /*!
240   \brief   Initialize the SBR_PREV_FRAME_DATA struct
241 */
242 void
initSbrPrevFrameData(HANDLE_SBR_PREV_FRAME_DATA h_prev_data,int timeSlots)243 initSbrPrevFrameData (HANDLE_SBR_PREV_FRAME_DATA h_prev_data, /*!< handle to struct SBR_PREV_FRAME_DATA */
244                       int timeSlots)                          /*!< Framelength in SBR-timeslots */
245 {
246   int i;
247 
248   /* Set previous energy and noise levels to 0 for the case
249      that decoding starts in the middle of a bitstream */
250   for (i=0; i < MAX_FREQ_COEFFS; i++)
251     h_prev_data->sfb_nrg_prev[i] = (FIXP_DBL)0;
252   for (i=0; i < MAX_NOISE_COEFFS; i++)
253     h_prev_data->prevNoiseLevel[i] = (FIXP_DBL)0;
254   for (i=0; i < MAX_INVF_BANDS; i++)
255     h_prev_data->sbr_invf_mode[i] = INVF_OFF;
256 
257   h_prev_data->stopPos = timeSlots;
258   h_prev_data->coupling = COUPLING_OFF;
259   h_prev_data->ampRes = 0;
260 }
261 
262 
263 /*!
264   \brief   Read header data from bitstream
265 
266   \return  error status - 0 if ok
267 */
268 SBR_HEADER_STATUS
sbrGetHeaderData(HANDLE_SBR_HEADER_DATA hHeaderData,HANDLE_FDK_BITSTREAM hBs,const UINT flags,const int fIsSbrData)269 sbrGetHeaderData (HANDLE_SBR_HEADER_DATA hHeaderData,
270                   HANDLE_FDK_BITSTREAM   hBs,
271                   const UINT             flags,
272                   const int              fIsSbrData)
273 {
274   SBR_HEADER_DATA_BS *pBsData;
275   SBR_HEADER_DATA_BS lastHeader;
276   SBR_HEADER_DATA_BS_INFO lastInfo;
277   int headerExtra1=0, headerExtra2=0;
278 
279   /* Copy SBR bit stream header to temporary header */
280   lastHeader = hHeaderData->bs_data;
281   lastInfo   = hHeaderData->bs_info;
282 
283   /* Read new header from bitstream */
284   {
285     pBsData = &hHeaderData->bs_data;
286   }
287 
288   {
289     hHeaderData->bs_info.ampResolution = FDKreadBits (hBs, 1);
290   }
291 
292   pBsData->startFreq = FDKreadBits (hBs, 4);
293   pBsData->stopFreq = FDKreadBits (hBs, 4);
294 
295   {
296     hHeaderData->bs_info.xover_band = FDKreadBits (hBs, 3);
297     FDKreadBits (hBs, 2);
298   }
299 
300   headerExtra1 = FDKreadBits (hBs, 1);
301   headerExtra2 = FDKreadBits (hBs, 1);
302 
303   /* Handle extra header information */
304   if( headerExtra1)
305   {
306     pBsData->freqScale = FDKreadBits (hBs, 2);
307     pBsData->alterScale = FDKreadBits (hBs, 1);
308     pBsData->noise_bands = FDKreadBits (hBs, 2);
309   }
310   else {
311     pBsData->freqScale   = 2;
312     pBsData->alterScale  = 1;
313     pBsData->noise_bands = 2;
314   }
315 
316   if (headerExtra2) {
317     pBsData->limiterBands = FDKreadBits (hBs, 2);
318     pBsData->limiterGains = FDKreadBits (hBs, 2);
319     pBsData->interpolFreq = FDKreadBits (hBs, 1);
320     pBsData->smoothingLength = FDKreadBits (hBs, 1);
321   }
322   else {
323     pBsData->limiterBands    = 2;
324     pBsData->limiterGains    = 2;
325     pBsData->interpolFreq    = 1;
326     pBsData->smoothingLength = 1;
327   }
328 
329   /* Look for new settings. IEC 14496-3, 4.6.18.3.1 */
330   if(hHeaderData->syncState < SBR_HEADER ||
331      lastHeader.startFreq   != pBsData->startFreq   ||
332      lastHeader.stopFreq    != pBsData->stopFreq    ||
333      lastHeader.freqScale   != pBsData->freqScale   ||
334      lastHeader.alterScale  != pBsData->alterScale  ||
335      lastHeader.noise_bands != pBsData->noise_bands ||
336      lastInfo.xover_band    != hHeaderData->bs_info.xover_band) {
337     return HEADER_RESET; /* New settings */
338   }
339 
340   return HEADER_OK;
341 }
342 
343 /*!
344   \brief   Get missing harmonics parameters (only used for AAC+SBR)
345 
346   \return  error status - 0 if ok
347 */
348 int
sbrGetSyntheticCodedData(HANDLE_SBR_HEADER_DATA hHeaderData,HANDLE_SBR_FRAME_DATA hFrameData,HANDLE_FDK_BITSTREAM hBs)349 sbrGetSyntheticCodedData(HANDLE_SBR_HEADER_DATA hHeaderData,
350                          HANDLE_SBR_FRAME_DATA  hFrameData,
351                          HANDLE_FDK_BITSTREAM   hBs)
352 {
353   int i, bitsRead = 0;
354 
355   int flag = FDKreadBits(hBs,1);
356   bitsRead++;
357 
358   if(flag){
359     for(i=0;i<hHeaderData->freqBandData.nSfb[1];i++){
360       hFrameData->addHarmonics[i]  = FDKreadBits (hBs, 1 );
361       bitsRead++;
362     }
363   }
364   else {
365     for(i=0; i<MAX_FREQ_COEFFS; i++)
366       hFrameData->addHarmonics[i]  = 0;
367   }
368   return(bitsRead);
369 }
370 
371 /*!
372   \brief      Reads extension data from the bitstream
373 
374   The bitstream format allows up to 4 kinds of extended data element.
375   Extended data may contain several elements, each identified by a 2-bit-ID.
376   So far, no extended data elements are defined hence the first 2 parameters
377   are unused. The data should be skipped in order to update the number
378   of read bits for the consistency check in applySBR().
379 */
extractExtendedData(HANDLE_SBR_HEADER_DATA hHeaderData,HANDLE_FDK_BITSTREAM hBs,HANDLE_PS_DEC hParametricStereoDec)380 static int  extractExtendedData(
381                                 HANDLE_SBR_HEADER_DATA hHeaderData,    /*!< handle to SBR header */
382                                 HANDLE_FDK_BITSTREAM   hBs             /*!< Handle to the bit buffer */
383                                ,HANDLE_PS_DEC hParametricStereoDec     /*!< Parametric Stereo Decoder */
384                                 ) {
385   INT nBitsLeft;
386   int extended_data;
387   int i, frameOk = 1;
388 
389 
390   extended_data = FDKreadBits(hBs, 1);
391 
392   if (extended_data) {
393     int cnt;
394     int bPsRead = 0;
395 
396     cnt = FDKreadBits(hBs, 4);
397     if (cnt == (1<<4)-1)
398       cnt += FDKreadBits(hBs, 8);
399 
400 
401     nBitsLeft = 8 * cnt;
402 
403     /* sanity check for cnt */
404     if (nBitsLeft > (INT)FDKgetValidBits(hBs)) {
405       /* limit nBitsLeft */
406       nBitsLeft = (INT)FDKgetValidBits(hBs);
407       /* set frame error */
408       frameOk = 0;
409     }
410 
411     while (nBitsLeft > 7) {
412       int extension_id = FDKreadBits(hBs, 2);
413       nBitsLeft -= 2;
414 
415       switch(extension_id) {
416 
417 
418 
419         case EXTENSION_ID_PS_CODING:
420 
421         /* Read PS data from bitstream */
422 
423         if (hParametricStereoDec != NULL) {
424           if(bPsRead && !hParametricStereoDec->bsData[hParametricStereoDec->bsReadSlot].mpeg.bPsHeaderValid) {
425             cnt = nBitsLeft >> 3; /* number of remaining bytes */
426             for (i=0; i<cnt; i++)
427               FDKreadBits(hBs, 8);
428             nBitsLeft -= cnt * 8;
429           } else {
430             nBitsLeft -= ReadPsData(hParametricStereoDec, hBs, nBitsLeft);
431             bPsRead = 1;
432           }
433         }
434 
435           /* parametric stereo detected, could set channelMode accordingly here  */
436           /*                                                                     */
437           /* "The usage of this parametric stereo extension to HE-AAC is         */
438           /* signalled implicitly in the bitstream. Hence, if an sbr_extension() */
439           /* with bs_extension_id==EXTENSION_ID_PS is found in the SBR part of   */
440           /* the bitstream, a decoder supporting the combination of SBR and PS   */
441           /* shall operate the PS tool to generate a stereo output signal."      */
442           /* source: ISO/IEC 14496-3:2001/FDAM 2:2004(E)                         */
443 
444         break;
445 
446 
447       default:
448         cnt = nBitsLeft >> 3; /* number of remaining bytes */
449         for (i=0; i<cnt; i++)
450           FDKreadBits(hBs, 8);
451         nBitsLeft -= cnt * 8;
452         break;
453       }
454     }
455 
456     if (nBitsLeft < 0) {
457       frameOk = 0;
458       goto bail;
459     }
460     else {
461       /* Read fill bits for byte alignment */
462       FDKreadBits(hBs, nBitsLeft);
463     }
464   }
465 
466 bail:
467   return (frameOk);
468 }
469 
470 
471 /*!
472   \brief   Read bitstream elements of one channel
473 
474   \return  SbrFrameOK:  1=ok, 0=error
475 */
476 int
sbrGetSingleChannelElement(HANDLE_SBR_HEADER_DATA hHeaderData,HANDLE_SBR_FRAME_DATA hFrameData,HANDLE_FDK_BITSTREAM hBs,HANDLE_PS_DEC hParametricStereoDec,const UINT flags,const int overlap)477 sbrGetSingleChannelElement (HANDLE_SBR_HEADER_DATA hHeaderData,          /*!< Static control data */
478                             HANDLE_SBR_FRAME_DATA  hFrameData,           /*!< Control data of current frame */
479                             HANDLE_FDK_BITSTREAM   hBs,                  /*!< Handle to struct BIT_BUF */
480                             HANDLE_PS_DEC          hParametricStereoDec, /*!< Handle to PS decoder */
481                             const UINT             flags,
482                             const int              overlap
483                            )
484 {
485   int i;
486 
487 
488   hFrameData->coupling = COUPLING_OFF;
489 
490   {
491     /* Reserved bits */
492     if (FDKreadBits(hBs, 1)) {  /* bs_data_extra */
493       FDKreadBits(hBs, 4);
494       if (flags & SBRDEC_SYNTAX_SCAL) {
495         FDKreadBits(hBs, 4);
496       }
497     }
498   }
499 
500   if (flags & SBRDEC_SYNTAX_SCAL) {
501     FDKreadBits (hBs, 1);     /* bs_coupling */
502   }
503 
504   /*
505     Grid control
506   */
507   if ( !extractFrameInfo ( hBs, hHeaderData, hFrameData, 1, flags) )
508    return 0;
509 
510   if ( !checkFrameInfo (&hFrameData->frameInfo, hHeaderData->numberTimeSlots, overlap, hHeaderData->timeStep) )
511     return 0;
512 
513 
514   /*
515     Fetch domain vectors (time or frequency direction for delta-coding)
516   */
517   sbrGetDirectionControlData (hFrameData, hBs);
518 
519   for (i=0; i<hHeaderData->freqBandData.nInvfBands; i++) {
520     hFrameData->sbr_invf_mode[i] =
521       (INVF_MODE) FDKreadBits (hBs, 2);
522   }
523 
524 
525 
526   /* raw data */
527   if ( !sbrGetEnvelope (hHeaderData, hFrameData, hBs, flags) )
528     return 0;
529 
530 
531   sbrGetNoiseFloorData (hHeaderData, hFrameData, hBs);
532 
533   sbrGetSyntheticCodedData(hHeaderData, hFrameData, hBs);
534 
535   {
536     /* sbr extended data */
537     if (! extractExtendedData(
538                                hHeaderData,
539                                hBs
540                               ,hParametricStereoDec
541                                )) {
542       return 0;
543     }
544   }
545 
546   return 1;
547 }
548 
549 
550 
551 /*!
552   \brief      Read bitstream elements of a channel pair
553   \return     SbrFrameOK
554 */
555 int
sbrGetChannelPairElement(HANDLE_SBR_HEADER_DATA hHeaderData,HANDLE_SBR_FRAME_DATA hFrameDataLeft,HANDLE_SBR_FRAME_DATA hFrameDataRight,HANDLE_FDK_BITSTREAM hBs,const UINT flags,const int overlap)556 sbrGetChannelPairElement (HANDLE_SBR_HEADER_DATA hHeaderData,    /*!< Static control data */
557                           HANDLE_SBR_FRAME_DATA  hFrameDataLeft, /*!< Dynamic control data for first channel */
558                           HANDLE_SBR_FRAME_DATA  hFrameDataRight,/*!< Dynamic control data for second channel */
559                           HANDLE_FDK_BITSTREAM   hBs,            /*!< handle to struct BIT_BUF */
560                           const UINT flags,
561                           const int overlap )
562 {
563   int i, bit;
564 
565 
566   /* Reserved bits */
567   if (FDKreadBits(hBs, 1)) {  /* bs_data_extra */
568     FDKreadBits(hBs, 4);
569     FDKreadBits(hBs, 4);
570   }
571 
572   /* Read coupling flag */
573   bit = FDKreadBits (hBs, 1);
574 
575   if (bit) {
576     hFrameDataLeft->coupling = COUPLING_LEVEL;
577     hFrameDataRight->coupling = COUPLING_BAL;
578   }
579   else {
580     hFrameDataLeft->coupling = COUPLING_OFF;
581     hFrameDataRight->coupling = COUPLING_OFF;
582   }
583 
584 
585   /*
586     Grid control
587   */
588   if ( !extractFrameInfo (hBs, hHeaderData, hFrameDataLeft, 2, flags) )
589     return 0;
590 
591   if ( !checkFrameInfo (&hFrameDataLeft->frameInfo, hHeaderData->numberTimeSlots, overlap, hHeaderData->timeStep) )
592     return 0;
593 
594   if (hFrameDataLeft->coupling) {
595     FDKmemcpy (&hFrameDataRight->frameInfo, &hFrameDataLeft->frameInfo, sizeof(FRAME_INFO));
596     hFrameDataRight->ampResolutionCurrentFrame = hFrameDataLeft->ampResolutionCurrentFrame;
597   }
598   else {
599     if ( !extractFrameInfo (hBs, hHeaderData, hFrameDataRight, 2, flags) )
600       return 0;
601 
602     if ( !checkFrameInfo (&hFrameDataRight->frameInfo, hHeaderData->numberTimeSlots, overlap, hHeaderData->timeStep) )
603       return 0;
604   }
605 
606   /*
607     Fetch domain vectors (time or frequency direction for delta-coding)
608   */
609   sbrGetDirectionControlData (hFrameDataLeft, hBs);
610   sbrGetDirectionControlData (hFrameDataRight, hBs);
611 
612   for (i=0; i<hHeaderData->freqBandData.nInvfBands; i++) {
613     hFrameDataLeft->sbr_invf_mode[i] = (INVF_MODE) FDKreadBits (hBs, 2);
614   }
615 
616   if (hFrameDataLeft->coupling) {
617     for (i=0; i<hHeaderData->freqBandData.nInvfBands; i++) {
618       hFrameDataRight->sbr_invf_mode[i] = hFrameDataLeft->sbr_invf_mode[i];
619     }
620 
621 
622     if ( !sbrGetEnvelope (hHeaderData, hFrameDataLeft, hBs, flags) ) {
623       return 0;
624     }
625 
626     sbrGetNoiseFloorData (hHeaderData, hFrameDataLeft, hBs);
627 
628     if ( !sbrGetEnvelope (hHeaderData, hFrameDataRight, hBs, flags) ) {
629       return 0;
630     }
631   }
632   else {
633 
634     for (i=0; i<hHeaderData->freqBandData.nInvfBands; i++) {
635       hFrameDataRight->sbr_invf_mode[i] = (INVF_MODE) FDKreadBits (hBs, 2);
636     }
637 
638 
639 
640     if ( !sbrGetEnvelope (hHeaderData, hFrameDataLeft, hBs, flags) )
641       return 0;
642 
643     if ( !sbrGetEnvelope (hHeaderData, hFrameDataRight, hBs, flags) )
644       return 0;
645 
646     sbrGetNoiseFloorData (hHeaderData, hFrameDataLeft, hBs);
647 
648   }
649   sbrGetNoiseFloorData (hHeaderData, hFrameDataRight, hBs);
650 
651   sbrGetSyntheticCodedData(hHeaderData, hFrameDataLeft, hBs);
652   sbrGetSyntheticCodedData(hHeaderData, hFrameDataRight, hBs);
653 
654   {
655     if (! extractExtendedData(
656                                hHeaderData,
657                                hBs
658                               ,NULL
659                              ) ) {
660       return 0;
661     }
662   }
663 
664   return 1;
665 }
666 
667 
668 
669 
670 /*!
671   \brief   Read direction control data from bitstream
672 */
673 void
sbrGetDirectionControlData(HANDLE_SBR_FRAME_DATA h_frame_data,HANDLE_FDK_BITSTREAM hBs)674 sbrGetDirectionControlData (HANDLE_SBR_FRAME_DATA h_frame_data, /*!< handle to struct SBR_FRAME_DATA */
675                             HANDLE_FDK_BITSTREAM  hBs)          /*!< handle to struct BIT_BUF */
676 {
677   int i;
678 
679   for (i = 0; i < h_frame_data->frameInfo.nEnvelopes; i++) {
680     h_frame_data->domain_vec[i] = FDKreadBits (hBs, 1);
681   }
682 
683   for (i = 0; i < h_frame_data->frameInfo.nNoiseEnvelopes; i++) {
684     h_frame_data->domain_vec_noise[i] = FDKreadBits (hBs, 1);
685   }
686 }
687 
688 
689 
690 /*!
691   \brief   Read noise-floor-level data from bitstream
692 */
693 void
sbrGetNoiseFloorData(HANDLE_SBR_HEADER_DATA hHeaderData,HANDLE_SBR_FRAME_DATA h_frame_data,HANDLE_FDK_BITSTREAM hBs)694 sbrGetNoiseFloorData (HANDLE_SBR_HEADER_DATA hHeaderData,  /*!< Static control data */
695                       HANDLE_SBR_FRAME_DATA  h_frame_data, /*!< handle to struct SBR_FRAME_DATA */
696                       HANDLE_FDK_BITSTREAM   hBs)          /*!< handle to struct BIT_BUF */
697 {
698   int i,j;
699   int delta;
700   COUPLING_MODE coupling;
701   int noNoiseBands = hHeaderData->freqBandData.nNfb;
702 
703   Huffman hcb_noiseF;
704   Huffman hcb_noise;
705   int envDataTableCompFactor;
706 
707   coupling = h_frame_data->coupling;
708 
709 
710   /*
711     Select huffman codebook depending on coupling mode
712   */
713   if (coupling == COUPLING_BAL) {
714     hcb_noise = (Huffman)&FDK_sbrDecoder_sbr_huffBook_NoiseBalance11T;
715     hcb_noiseF = (Huffman)&FDK_sbrDecoder_sbr_huffBook_EnvBalance11F;  /* "sbr_huffBook_NoiseBalance11F" */
716     envDataTableCompFactor = 1;
717   }
718   else {
719     hcb_noise = (Huffman)&FDK_sbrDecoder_sbr_huffBook_NoiseLevel11T;
720     hcb_noiseF = (Huffman)&FDK_sbrDecoder_sbr_huffBook_EnvLevel11F;    /* "sbr_huffBook_NoiseLevel11F" */
721     envDataTableCompFactor = 0;
722   }
723 
724   /*
725     Read raw noise-envelope data
726   */
727   for (i=0; i<h_frame_data->frameInfo.nNoiseEnvelopes; i++) {
728 
729 
730     if (h_frame_data->domain_vec_noise[i] == 0) {
731       if (coupling == COUPLING_BAL) {
732         h_frame_data->sbrNoiseFloorLevel[i*noNoiseBands] =
733           (FIXP_SGL) (((int)FDKreadBits (hBs, 5)) << envDataTableCompFactor);
734       }
735       else {
736         h_frame_data->sbrNoiseFloorLevel[i*noNoiseBands] =
737           (FIXP_SGL) (int)FDKreadBits (hBs, 5);
738       }
739 
740       for (j = 1; j < noNoiseBands; j++) {
741         delta = DecodeHuffmanCW(hcb_noiseF, hBs);
742         h_frame_data->sbrNoiseFloorLevel[i*noNoiseBands+j] = (FIXP_SGL) (delta << envDataTableCompFactor);
743       }
744     }
745     else {
746       for (j = 0; j < noNoiseBands; j++) {
747         delta = DecodeHuffmanCW(hcb_noise, hBs);
748         h_frame_data->sbrNoiseFloorLevel[i*noNoiseBands+j] = (FIXP_SGL) (delta << envDataTableCompFactor);
749       }
750     }
751   }
752 }
753 
754 
755 /*!
756   \brief   Read envelope data from bitstream
757 */
758 static int
sbrGetEnvelope(HANDLE_SBR_HEADER_DATA hHeaderData,HANDLE_SBR_FRAME_DATA h_frame_data,HANDLE_FDK_BITSTREAM hBs,const UINT flags)759 sbrGetEnvelope (HANDLE_SBR_HEADER_DATA hHeaderData,  /*!< Static control data */
760                 HANDLE_SBR_FRAME_DATA  h_frame_data, /*!< handle to struct SBR_FRAME_DATA */
761                 HANDLE_FDK_BITSTREAM   hBs,          /*!< handle to struct BIT_BUF */
762                 const UINT             flags)
763 {
764   int i, j;
765   UCHAR no_band[MAX_ENVELOPES];
766   int delta = 0;
767   int offset = 0;
768   COUPLING_MODE coupling = h_frame_data->coupling;
769   int ampRes = hHeaderData->bs_info.ampResolution;
770   int nEnvelopes = h_frame_data->frameInfo.nEnvelopes;
771   int envDataTableCompFactor;
772   int start_bits, start_bits_balance;
773   Huffman hcb_t, hcb_f;
774 
775   h_frame_data->nScaleFactors = 0;
776 
777   if ( (h_frame_data->frameInfo.frameClass == 0) && (nEnvelopes == 1) ) {
778     if (flags & SBRDEC_ELD_GRID)
779       ampRes = h_frame_data->ampResolutionCurrentFrame;
780     else
781       ampRes = 0;
782   }
783   h_frame_data->ampResolutionCurrentFrame = ampRes;
784 
785   /*
786     Set number of bits for first value depending on amplitude resolution
787   */
788   if(ampRes == 1)
789   {
790     start_bits = 6;
791     start_bits_balance = 5;
792   }
793   else
794   {
795     start_bits = 7;
796     start_bits_balance = 6;
797   }
798 
799   /*
800     Calculate number of values for each envelope and alltogether
801   */
802   for (i = 0; i < nEnvelopes; i++) {
803     no_band[i] = hHeaderData->freqBandData.nSfb[h_frame_data->frameInfo.freqRes[i]];
804     h_frame_data->nScaleFactors += no_band[i];
805   }
806   if (h_frame_data->nScaleFactors > MAX_NUM_ENVELOPE_VALUES)
807     return 0;
808 
809   /*
810     Select Huffman codebook depending on coupling mode and amplitude resolution
811   */
812   if (coupling == COUPLING_BAL) {
813     envDataTableCompFactor = 1;
814     if (ampRes == 0) {
815       hcb_t = (Huffman)&FDK_sbrDecoder_sbr_huffBook_EnvBalance10T;
816       hcb_f = (Huffman)&FDK_sbrDecoder_sbr_huffBook_EnvBalance10F;
817     }
818     else {
819       hcb_t = (Huffman)&FDK_sbrDecoder_sbr_huffBook_EnvBalance11T;
820       hcb_f = (Huffman)&FDK_sbrDecoder_sbr_huffBook_EnvBalance11F;
821     }
822   }
823   else {
824     envDataTableCompFactor = 0;
825     if (ampRes == 0) {
826       hcb_t = (Huffman)&FDK_sbrDecoder_sbr_huffBook_EnvLevel10T;
827       hcb_f = (Huffman)&FDK_sbrDecoder_sbr_huffBook_EnvLevel10F;
828     }
829     else {
830       hcb_t = (Huffman)&FDK_sbrDecoder_sbr_huffBook_EnvLevel11T;
831       hcb_f = (Huffman)&FDK_sbrDecoder_sbr_huffBook_EnvLevel11F;
832     }
833   }
834 
835   /*
836     Now read raw envelope data
837   */
838   for (j = 0, offset = 0; j < nEnvelopes; j++) {
839 
840 
841     if (h_frame_data->domain_vec[j] == 0) {
842       if (coupling == COUPLING_BAL) {
843         h_frame_data->iEnvelope[offset] =
844           (FIXP_SGL) (( (int)FDKreadBits(hBs, start_bits_balance)) << envDataTableCompFactor);
845       }
846       else {
847         h_frame_data->iEnvelope[offset] =
848           (FIXP_SGL) (int)FDKreadBits (hBs, start_bits);
849       }
850     }
851 
852     for (i = (1 - h_frame_data->domain_vec[j]); i < no_band[j]; i++) {
853 
854       if (h_frame_data->domain_vec[j] == 0) {
855         delta = DecodeHuffmanCW(hcb_f, hBs);
856       }
857       else {
858         delta = DecodeHuffmanCW(hcb_t, hBs);
859       }
860 
861       h_frame_data->iEnvelope[offset + i] = (FIXP_SGL) (delta << envDataTableCompFactor);
862     }
863     offset += no_band[j];
864   }
865 
866 #if ENV_EXP_FRACT
867   /* Convert from int to scaled fract (ENV_EXP_FRACT bits for the fractional part) */
868   for (i = 0; i < h_frame_data->nScaleFactors; i++) {
869     h_frame_data->iEnvelope[i] <<= ENV_EXP_FRACT;
870   }
871 #endif
872 
873   return 1;
874 }
875 
876 
877 //static const FRAME_INFO v_frame_info1_8 = { 0, 1, {0, 8}, {1}, -1, 1, {0, 8} };
878 static const FRAME_INFO v_frame_info2_8 = { 0, 2, {0, 4, 8}, {1, 1}, -1, 2, {0, 4, 8} };
879 static const FRAME_INFO v_frame_info4_8 = { 0, 4, {0, 2, 4, 6, 8}, {1, 1, 1, 1}, -1, 2, {0, 4, 8} };
880 
881 /***************************************************************************/
882 /*!
883   \brief    Generates frame info for FIXFIXonly frame class used for low delay version
884 
885   \return   nothing
886  ****************************************************************************/
generateFixFixOnly(FRAME_INFO * hSbrFrameInfo,int tranPosInternal,int numberTimeSlots)887  static void generateFixFixOnly ( FRAME_INFO *hSbrFrameInfo,
888                                   int tranPosInternal,
889                                   int numberTimeSlots
890                                 )
891 {
892     int nEnv, i, tranIdx;
893     const int *pTable;
894 
895     switch (numberTimeSlots) {
896         case 8:
897             pTable = FDK_sbrDecoder_envelopeTable_8[tranPosInternal];
898             break;
899         case 15:
900             pTable = FDK_sbrDecoder_envelopeTable_15[tranPosInternal];
901             break;
902         case 16:
903             pTable = FDK_sbrDecoder_envelopeTable_16[tranPosInternal];
904             break;
905         default:
906             FDK_ASSERT(0);
907     }
908 
909     /* look number of envelopes in table */
910     nEnv = pTable[0];
911     /* look up envelope distribution in table */
912     for (i=1; i<nEnv; i++)
913         hSbrFrameInfo->borders[i] = pTable[i+2];
914     /* open and close frame border */
915     hSbrFrameInfo->borders[0]    = 0;
916     hSbrFrameInfo->borders[nEnv] = numberTimeSlots;
917     hSbrFrameInfo->nEnvelopes = nEnv;
918 
919    /* transient idx */
920     tranIdx = hSbrFrameInfo->tranEnv = pTable[1];
921 
922     /* add noise floors */
923     hSbrFrameInfo->bordersNoise[0] = 0;
924     hSbrFrameInfo->bordersNoise[1] = hSbrFrameInfo->borders[tranIdx?tranIdx:1];
925     hSbrFrameInfo->bordersNoise[2] = numberTimeSlots;
926     /* nEnv is always > 1, so nNoiseEnvelopes is always 2 (IEC 14496-3 4.6.19.3.2) */
927     hSbrFrameInfo->nNoiseEnvelopes = 2;
928 }
929 
930 /*!
931   \brief  Extracts LowDelaySBR control data from the bitstream.
932 
933   \return zero for bitstream error, one for correct.
934 */
935 static int
extractLowDelayGrid(HANDLE_FDK_BITSTREAM hBitBuf,HANDLE_SBR_HEADER_DATA hHeaderData,HANDLE_SBR_FRAME_DATA h_frame_data,int timeSlots)936 extractLowDelayGrid (HANDLE_FDK_BITSTREAM hBitBuf,          /*!< bitbuffer handle */
937                      HANDLE_SBR_HEADER_DATA hHeaderData,
938                      HANDLE_SBR_FRAME_DATA h_frame_data, /*!< contains the FRAME_INFO struct to be filled */
939                      int timeSlots
940                     )
941 {
942   FRAME_INFO * pFrameInfo = &h_frame_data->frameInfo;
943   INT numberTimeSlots = hHeaderData->numberTimeSlots;
944   INT temp = 0, k;
945 
946       /* FIXFIXonly framing case */
947       h_frame_data->frameInfo.frameClass = 0;
948 
949       /* get the transient position from the bitstream */
950       switch (timeSlots){
951         case 8:
952           /* 3bit transient position (temp={0;..;7}) */
953           temp = FDKreadBits( hBitBuf, 3);
954           break;
955 
956         case 16:
957         case 15:
958           /* 4bit transient position (temp={0;..;15}) */
959           temp = FDKreadBits( hBitBuf, 4);
960           break;
961 
962         default:
963           return 0;
964       }
965 
966       /* calculate borders according to the transient position */
967       generateFixFixOnly ( pFrameInfo,
968                            temp,
969                            numberTimeSlots
970                          );
971 
972       /* decode freq res: */
973       for (k = 0; k < pFrameInfo->nEnvelopes; k++) {
974           pFrameInfo->freqRes[k] = (UCHAR) FDKreadBits (hBitBuf, 1); /* f = F [1 bits] */
975       }
976 
977 
978   return 1;
979 }
980 
981 /*!
982   \brief   Extract the frame information (structure FRAME_INFO) from the bitstream
983   \return  Zero for bitstream error, one for correct.
984 */
985 int
extractFrameInfo(HANDLE_FDK_BITSTREAM hBs,HANDLE_SBR_HEADER_DATA hHeaderData,HANDLE_SBR_FRAME_DATA h_frame_data,const UINT nrOfChannels,const UINT flags)986 extractFrameInfo ( HANDLE_FDK_BITSTREAM   hBs,          /*!< bitbuffer handle */
987                    HANDLE_SBR_HEADER_DATA hHeaderData,  /*!< Static control data */
988                    HANDLE_SBR_FRAME_DATA  h_frame_data, /*!< pointer to memory where the frame-info will be stored */
989                    const UINT             nrOfChannels,
990                    const UINT             flags
991                  )
992 {
993   FRAME_INFO * pFrameInfo = &h_frame_data->frameInfo;
994   int numberTimeSlots = hHeaderData->numberTimeSlots;
995   int pointer_bits = 0, nEnv = 0, b = 0, border, i, n = 0,
996     k, p, aL, aR, nL, nR,
997     temp = 0, staticFreqRes;
998   UCHAR frameClass;
999 
1000   if (flags & SBRDEC_ELD_GRID) {
1001       /* CODEC_AACLD (LD+SBR) only uses the normal 0 Grid for non-transient Frames and the LowDelayGrid for transient Frames */
1002       frameClass = FDKreadBits (hBs, 1); /* frameClass = [1 bit] */
1003       if ( frameClass == 1 ) {
1004         /* if frameClass == 1, extract LowDelaySbrGrid, otherwise extract normal SBR-Grid for FIXIFX */
1005         /* extract the AACLD-Sbr-Grid */
1006         pFrameInfo->frameClass = frameClass;
1007         extractLowDelayGrid (hBs, hHeaderData, h_frame_data, numberTimeSlots);
1008         return 1;
1009       }
1010   } else
1011   {
1012     frameClass = FDKreadBits (hBs, 2); /* frameClass = C [2 bits] */
1013   }
1014 
1015 
1016   switch (frameClass) {
1017   case 0:
1018     temp = FDKreadBits (hBs, 2);     /* E [2 bits ] */
1019     nEnv = (int) (1 << temp);    /* E -> e */
1020 
1021     if ((flags & SBRDEC_ELD_GRID) && (nEnv == 1))
1022       h_frame_data->ampResolutionCurrentFrame = FDKreadBits( hBs, 1); /* new ELD Syntax 07-11-09 */
1023 
1024     staticFreqRes = FDKreadBits (hBs, 1);
1025 
1026     {
1027       if (nEnv > MAX_ENVELOPES_HEAAC)
1028         return 0;
1029     }
1030 
1031     b = nEnv + 1;
1032     switch (nEnv) {
1033     case 1:
1034       switch (numberTimeSlots) {
1035         case 15:
1036           FDKmemcpy (pFrameInfo, &FDK_sbrDecoder_sbr_frame_info1_15, sizeof(FRAME_INFO));
1037           break;
1038         case 16:
1039           FDKmemcpy (pFrameInfo, &FDK_sbrDecoder_sbr_frame_info1_16, sizeof(FRAME_INFO));
1040           break;
1041         default:
1042           FDK_ASSERT(0);
1043       }
1044       break;
1045     case 2:
1046       switch (numberTimeSlots) {
1047         case 15:
1048           FDKmemcpy (pFrameInfo, &FDK_sbrDecoder_sbr_frame_info2_15, sizeof(FRAME_INFO));
1049           break;
1050         case 16:
1051           FDKmemcpy (pFrameInfo, &FDK_sbrDecoder_sbr_frame_info2_16, sizeof(FRAME_INFO));
1052           break;
1053         default:
1054           FDK_ASSERT(0);
1055       }
1056       break;
1057     case 4:
1058       switch (numberTimeSlots) {
1059         case 15:
1060           FDKmemcpy (pFrameInfo, &FDK_sbrDecoder_sbr_frame_info4_15, sizeof(FRAME_INFO));
1061           break;
1062         case 16:
1063           FDKmemcpy (pFrameInfo, &FDK_sbrDecoder_sbr_frame_info4_16, sizeof(FRAME_INFO));
1064           break;
1065         default:
1066           FDK_ASSERT(0);
1067       }
1068       break;
1069     case 8:
1070 #if (MAX_ENVELOPES >= 8)
1071       switch (numberTimeSlots) {
1072         case 15:
1073           FDKmemcpy (pFrameInfo, &FDK_sbrDecoder_sbr_frame_info8_15, sizeof(FRAME_INFO));
1074           break;
1075         case 16:
1076           FDKmemcpy (pFrameInfo, &FDK_sbrDecoder_sbr_frame_info8_16, sizeof(FRAME_INFO));
1077           break;
1078         default:
1079           FDK_ASSERT(0);
1080       }
1081       break;
1082 #else
1083       return 0;
1084 #endif
1085     }
1086     /* Apply correct freqRes (High is default) */
1087     if (!staticFreqRes) {
1088       for (i = 0; i < nEnv ; i++)
1089         pFrameInfo->freqRes[i] = 0;
1090     }
1091 
1092     break;
1093   case 1:
1094   case 2:
1095     temp = FDKreadBits (hBs, 2);  /* A [2 bits] */
1096 
1097     n    = FDKreadBits (hBs, 2);  /* n = N [2 bits] */
1098 
1099     nEnv = n + 1;                             /* # envelopes */
1100     b = nEnv + 1;                             /* # borders   */
1101 
1102     break;
1103   }
1104 
1105   switch (frameClass) {
1106   case 1:
1107     /* Decode borders: */
1108     pFrameInfo->borders[0] = 0;               /* first border          */
1109     border = temp + numberTimeSlots;          /* A -> aR               */
1110     i = b-1;                                  /* frame info index for last border */
1111     pFrameInfo->borders[i] = border;          /* last border                      */
1112 
1113     for (k = 0; k < n; k++) {
1114       temp = FDKreadBits (hBs, 2);/* R [2 bits] */
1115       border -= (2 * temp + 2);               /* R -> r                */
1116       pFrameInfo->borders[--i] = border;
1117     }
1118 
1119 
1120     /* Decode pointer: */
1121     pointer_bits = DFRACT_BITS - 1 - CountLeadingBits((FIXP_DBL)(n+1));
1122     p = FDKreadBits (hBs, pointer_bits);     /* p = P [pointer_bits bits] */
1123 
1124     if (p > n+1)
1125       return 0;
1126 
1127     pFrameInfo->tranEnv = p ? n + 2 - p : -1;
1128 
1129 
1130     /* Decode freq res: */
1131     for (k = n; k >= 0; k--) {
1132       pFrameInfo->freqRes[k] = FDKreadBits (hBs, 1); /* f = F [1 bits] */
1133     }
1134 
1135 
1136     /* Calculate noise floor middle border: */
1137     if (p == 0 || p == 1)
1138       pFrameInfo->bordersNoise[1] = pFrameInfo->borders[n];
1139     else
1140       pFrameInfo->bordersNoise[1] = pFrameInfo->borders[pFrameInfo->tranEnv];
1141 
1142     break;
1143 
1144   case 2:
1145     /* Decode borders: */
1146     border = temp;                            /* A -> aL */
1147     pFrameInfo->borders[0] = border;          /* first border */
1148 
1149     for (k = 1; k <= n; k++) {
1150       temp = FDKreadBits (hBs, 2);/* R [2 bits] */
1151       border += (2 * temp + 2);               /* R -> r                */
1152       pFrameInfo->borders[k] = border;
1153     }
1154     pFrameInfo->borders[k] = numberTimeSlots; /* last border */
1155 
1156 
1157     /* Decode pointer: */
1158     pointer_bits = DFRACT_BITS - 1 - CountLeadingBits((FIXP_DBL)(n+1));
1159     p = FDKreadBits (hBs, pointer_bits);     /* p = P [pointer_bits bits] */
1160     if (p > n+1)
1161       return 0;
1162 
1163     if (p == 0 || p == 1)
1164       pFrameInfo->tranEnv = -1;
1165     else
1166       pFrameInfo->tranEnv = p - 1;
1167 
1168 
1169 
1170     /* Decode freq res: */
1171     for (k = 0; k <= n; k++) {
1172       pFrameInfo->freqRes[k] = FDKreadBits(hBs, 1); /* f = F [1 bits] */
1173     }
1174 
1175 
1176 
1177     /* Calculate noise floor middle border: */
1178     switch (p) {
1179     case 0:
1180       pFrameInfo->bordersNoise[1] = pFrameInfo->borders[1];
1181       break;
1182     case 1:
1183       pFrameInfo->bordersNoise[1] = pFrameInfo->borders[n];
1184       break;
1185     default:
1186       pFrameInfo->bordersNoise[1] = pFrameInfo->borders[pFrameInfo->tranEnv];
1187       break;
1188     }
1189 
1190     break;
1191 
1192   case 3:
1193     /* v_ctrlSignal = [frameClass,aL,aR,nL,nR,v_rL,v_rR,p,v_fLR]; */
1194 
1195     aL = FDKreadBits (hBs, 2);       /* AL [2 bits], AL -> aL */
1196 
1197     aR = FDKreadBits (hBs, 2) + numberTimeSlots;     /* AR [2 bits], AR -> aR */
1198 
1199     nL = FDKreadBits (hBs, 2);       /* nL = NL [2 bits] */
1200 
1201     nR = FDKreadBits (hBs, 2);       /* nR = NR [2 bits] */
1202 
1203 
1204 
1205     /*-------------------------------------------------------------------------
1206       Calculate help variables
1207       --------------------------------------------------------------------------*/
1208 
1209     /* general: */
1210     nEnv = nL + nR + 1;            /* # envelopes */
1211     if (nEnv > MAX_ENVELOPES)
1212       return 0;
1213     b = nEnv + 1;                  /* # borders   */
1214 
1215 
1216 
1217     /*-------------------------------------------------------------------------
1218       Decode envelopes
1219       --------------------------------------------------------------------------*/
1220 
1221 
1222     /* L-borders:   */
1223     border            = aL;                   /* first border */
1224     pFrameInfo->borders[0] = border;
1225 
1226     for (k = 1; k <= nL; k++) {
1227       temp = FDKreadBits (hBs, 2);/* R [2 bits] */
1228       border += (2 * temp + 2);               /* R -> r                */
1229       pFrameInfo->borders[k] = border;
1230     }
1231 
1232 
1233     /* R-borders:  */
1234     border = aR;                              /* last border */
1235     i      = nEnv;
1236 
1237     pFrameInfo->borders[i] = border;
1238 
1239     for (k = 0; k < nR; k++) {
1240       temp = FDKreadBits (hBs, 2);/* R [2 bits] */
1241       border -= (2 * temp + 2);               /* R -> r                */
1242       pFrameInfo->borders[--i] = border;
1243     }
1244 
1245 
1246     /* decode pointer: */
1247     pointer_bits = DFRACT_BITS - 1 - CountLeadingBits((FIXP_DBL)(nL+nR+1));
1248     p = FDKreadBits (hBs, pointer_bits);     /* p = P [pointer_bits bits] */
1249 
1250     if (p > nL+nR+1)
1251       return 0;
1252 
1253     pFrameInfo->tranEnv = p ? b - p : -1;
1254 
1255 
1256 
1257     /* decode freq res: */
1258     for (k = 0; k < nEnv; k++) {
1259       pFrameInfo->freqRes[k] = FDKreadBits(hBs, 1); /* f = F [1 bits] */
1260     }
1261 
1262 
1263 
1264     /*-------------------------------------------------------------------------
1265       Decode noise floors
1266       --------------------------------------------------------------------------*/
1267     pFrameInfo->bordersNoise[0] = aL;
1268 
1269     if (nEnv == 1) {
1270       /* 1 noise floor envelope: */
1271       pFrameInfo->bordersNoise[1] = aR;
1272     }
1273     else {
1274       /* 2 noise floor envelopes */
1275       if (p == 0 || p == 1)
1276         pFrameInfo->bordersNoise[1] = pFrameInfo->borders[nEnv - 1];
1277       else
1278         pFrameInfo->bordersNoise[1] = pFrameInfo->borders[pFrameInfo->tranEnv];
1279       pFrameInfo->bordersNoise[2] = aR;
1280     }
1281     break;
1282   }
1283 
1284 
1285   /*
1286     Store number of envelopes, noise floor envelopes and frame class
1287   */
1288   pFrameInfo->nEnvelopes = nEnv;
1289 
1290   if (nEnv == 1)
1291     pFrameInfo->nNoiseEnvelopes = 1;
1292   else
1293     pFrameInfo->nNoiseEnvelopes = 2;
1294 
1295   pFrameInfo->frameClass = frameClass;
1296 
1297   if (pFrameInfo->frameClass == 2 || pFrameInfo->frameClass == 1) {
1298     /* calculate noise floor first and last borders: */
1299     pFrameInfo->bordersNoise[0] = pFrameInfo->borders[0];
1300     pFrameInfo->bordersNoise[pFrameInfo->nNoiseEnvelopes] = pFrameInfo->borders[nEnv];
1301   }
1302 
1303 
1304   return 1;
1305 }
1306 
1307 
1308 /*!
1309   \brief   Check if the frameInfo vector has reasonable values.
1310   \return  Zero for error, one for correct
1311 */
1312 static int
checkFrameInfo(FRAME_INFO * pFrameInfo,int numberOfTimeSlots,int overlap,int timeStep)1313 checkFrameInfo (FRAME_INFO * pFrameInfo, /*!< pointer to frameInfo */
1314                 int numberOfTimeSlots,   /*!< QMF time slots per frame */
1315                 int overlap,             /*!< Amount of overlap QMF time slots */
1316                 int timeStep)            /*!< QMF slots to SBR slots step factor */
1317 {
1318   int maxPos,i,j;
1319   int startPos;
1320   int stopPos;
1321   int tranEnv;
1322   int startPosNoise;
1323   int stopPosNoise;
1324   int nEnvelopes = pFrameInfo->nEnvelopes;
1325   int nNoiseEnvelopes = pFrameInfo->nNoiseEnvelopes;
1326 
1327   if(nEnvelopes < 1 || nEnvelopes > MAX_ENVELOPES)
1328     return 0;
1329 
1330   if(nNoiseEnvelopes > MAX_NOISE_ENVELOPES)
1331     return 0;
1332 
1333   startPos        = pFrameInfo->borders[0];
1334   stopPos         = pFrameInfo->borders[nEnvelopes];
1335   tranEnv         = pFrameInfo->tranEnv;
1336   startPosNoise   = pFrameInfo->bordersNoise[0];
1337   stopPosNoise    = pFrameInfo->bordersNoise[nNoiseEnvelopes];
1338 
1339   if (overlap < 0 || overlap > (6)) {
1340     return 0;
1341   }
1342   if (timeStep < 1 || timeStep > 2) {
1343     return 0;
1344   }
1345   maxPos = numberOfTimeSlots + (overlap/timeStep);
1346 
1347   /* Check that the start and stop positions of the frame are reasonable values. */
1348   if( (startPos < 0) || (startPos >= stopPos) )
1349     return 0;
1350   if( startPos > maxPos-numberOfTimeSlots ) /* First env. must start in or directly after the overlap buffer */
1351     return 0;
1352   if( stopPos < numberOfTimeSlots ) /* One complete frame must be ready for output after processing */
1353     return 0;
1354   if(stopPos > maxPos)
1355     return 0;
1356 
1357   /* Check that the  start border for every envelope is strictly later in time */
1358   for(i=0;i<nEnvelopes;i++) {
1359     if(pFrameInfo->borders[i] >= pFrameInfo->borders[i+1])
1360       return 0;
1361   }
1362 
1363   /* Check that the envelope to be shortened is actually among the envelopes */
1364   if(tranEnv>nEnvelopes)
1365     return 0;
1366 
1367 
1368   /* Check the noise borders */
1369   if(nEnvelopes==1 && nNoiseEnvelopes>1)
1370     return 0;
1371 
1372   if(startPos != startPosNoise || stopPos != stopPosNoise)
1373     return 0;
1374 
1375 
1376   /* Check that the  start border for every noise-envelope is strictly later in time*/
1377   for(i=0; i<nNoiseEnvelopes; i++) {
1378     if(pFrameInfo->bordersNoise[i] >= pFrameInfo->bordersNoise[i+1])
1379       return 0;
1380   }
1381 
1382   /* Check that every noise border is the same as an envelope border*/
1383   for(i=0; i<nNoiseEnvelopes; i++) {
1384     startPosNoise = pFrameInfo->bordersNoise[i];
1385 
1386     for(j=0; j<nEnvelopes; j++) {
1387       if(pFrameInfo->borders[j] == startPosNoise)
1388         break;
1389     }
1390     if(j==nEnvelopes)
1391       return 0;
1392   }
1393 
1394   return 1;
1395 }
1396