1
2/* -----------------------------------------------------------------------------------------------------------
3Software License for The Fraunhofer FDK AAC Codec Library for Android
4
5� Copyright  1995 - 2013 Fraunhofer-Gesellschaft zur F�rderung der angewandten Forschung e.V.
6  All rights reserved.
7
8 1.    INTRODUCTION
9The Fraunhofer FDK AAC Codec Library for Android ("FDK AAC Codec") is software that implements
10the MPEG Advanced Audio Coding ("AAC") encoding and decoding scheme for digital audio.
11This FDK AAC Codec software is intended to be used on a wide variety of Android devices.
12
13AAC's HE-AAC and HE-AAC v2 versions are regarded as today's most efficient general perceptual
14audio codecs. AAC-ELD is considered the best-performing full-bandwidth communications codec by
15independent studies and is widely deployed. AAC has been standardized by ISO and IEC as part
16of the MPEG specifications.
17
18Patent licenses for necessary patent claims for the FDK AAC Codec (including those of Fraunhofer)
19may be obtained through Via Licensing (www.vialicensing.com) or through the respective patent owners
20individually for the purpose of encoding or decoding bit streams in products that are compliant with
21the ISO/IEC MPEG audio standards. Please note that most manufacturers of Android devices already license
22these patent claims through Via Licensing or directly from the patent owners, and therefore FDK AAC Codec
23software may already be covered under those patent licenses when it is used for those licensed purposes only.
24
25Commercially-licensed AAC software libraries, including floating-point versions with enhanced sound quality,
26are also available from Fraunhofer. Users are encouraged to check the Fraunhofer website for additional
27applications information and documentation.
28
292.    COPYRIGHT LICENSE
30
31Redistribution and use in source and binary forms, with or without modification, are permitted without
32payment of copyright license fees provided that you satisfy the following conditions:
33
34You must retain the complete text of this software license in redistributions of the FDK AAC Codec or
35your modifications thereto in source code form.
36
37You must retain the complete text of this software license in the documentation and/or other materials
38provided with redistributions of the FDK AAC Codec or your modifications thereto in binary form.
39You must make available free of charge copies of the complete source code of the FDK AAC Codec and your
40modifications thereto to recipients of copies in binary form.
41
42The name of Fraunhofer may not be used to endorse or promote products derived from this library without
43prior written permission.
44
45You may not charge copyright license fees for anyone to use, copy or distribute the FDK AAC Codec
46software or your modifications thereto.
47
48Your modified versions of the FDK AAC Codec must carry prominent notices stating that you changed the software
49and 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
533.    NO PATENT LICENSE
54
55NO EXPRESS OR IMPLIED LICENSES TO ANY PATENT CLAIMS, including without limitation the patents of Fraunhofer,
56ARE GRANTED BY THIS SOFTWARE LICENSE. Fraunhofer provides no warranty of patent non-infringement with
57respect to this software.
58
59You may use this FDK AAC Codec software or modifications thereto only for purposes that are authorized
60by appropriate patent licenses.
61
624.    DISCLAIMER
63
64This 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
66of merchantability and fitness for a particular purpose. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
67CONTRIBUTORS BE LIABLE for any direct, indirect, incidental, special, exemplary, or consequential damages,
68including but not limited to procurement of substitute goods or services; loss of use, data, or profits,
69or business interruption, however caused and on any theory of liability, whether in contract, strict
70liability, or tort (including negligence), arising in any way out of the use of this software, even if
71advised of the possibility of such damage.
72
735.    CONTACT INFORMATION
74
75Fraunhofer Institute for Integrated Circuits IIS
76Attention: Audio and Multimedia Departments - FDK AAC LL
77Am Wolfsmantel 33
7891058 Erlangen, Germany
79
80www.iis.fraunhofer.de/amm
81amm-info@iis.fraunhofer.de
82----------------------------------------------------------------------------------------------------------- */
83
84/*!
85  \file
86  \brief  Remaining SBR Bit Writing Routines
87*/
88
89#include "env_bit.h"
90#include "cmondata.h"
91
92
93#ifndef min
94#define min(a,b) ( a < b ? a:b)
95#endif
96
97#ifndef max
98#define max(a,b) ( a > b ? a:b)
99#endif
100
101/* ***************************** crcAdvance **********************************/
102/**
103 * @fn
104 * @brief    updates crc data register
105 * @return   none
106 *
107 * This function updates the crc register
108 *
109 */
110static void crcAdvance(USHORT crcPoly,
111                       USHORT crcMask,
112                       USHORT *crc,
113                       ULONG   bValue,
114                       INT     bBits
115                      )
116{
117  INT i;
118  USHORT flag;
119
120  for (i=bBits-1; i>=0; i--) {
121    flag = ((*crc) & crcMask) ? (1) : (0) ;
122    flag ^= (bValue & (1<<i)) ? (1) : (0) ;
123
124    (*crc)<<=1;
125    if(flag) (*crc) ^= crcPoly;
126  }
127}
128
129
130/* ***************************** FDKsbrEnc_InitSbrBitstream **********************************/
131/**
132 * @fn
133 * @brief    Inittialisation of sbr bitstream, write of dummy header and CRC
134 * @return   none
135 *
136 *
137 *
138 */
139
140INT  FDKsbrEnc_InitSbrBitstream(HANDLE_COMMON_DATA  hCmonData,
141                                UCHAR              *memoryBase,      /*!< Pointer to bitstream buffer */
142                                INT                 memorySize,      /*!< Length of bitstream buffer in bytes */
143                                HANDLE_FDK_CRCINFO  hCrcInfo,
144                                UINT                sbrSyntaxFlags)  /*!< SBR syntax flags */
145{
146  INT crcRegion = 0;
147
148  /* reset bit buffer */
149  FDKresetBitbuffer(&hCmonData->sbrBitbuf, BS_WRITER);
150
151  FDKinitBitStream(&hCmonData->tmpWriteBitbuf, memoryBase,
152                   memorySize, 0, BS_WRITER);
153
154  if (sbrSyntaxFlags & SBR_SYNTAX_CRC) {
155    if (sbrSyntaxFlags & SBR_SYNTAX_DRM_CRC)
156    { /* Init and start CRC region */
157      FDKwriteBits (&hCmonData->sbrBitbuf, 0x0, SI_SBR_DRM_CRC_BITS);
158      FDKcrcInit( hCrcInfo, 0x001d, 0xFFFF, SI_SBR_DRM_CRC_BITS );
159      crcRegion = FDKcrcStartReg( hCrcInfo, &hCmonData->sbrBitbuf, 0 );
160    } else {
161      FDKwriteBits (&hCmonData->sbrBitbuf, 0x0, SI_SBR_CRC_BITS);
162    }
163  }
164
165  return (crcRegion);
166}
167
168
169/* ************************** FDKsbrEnc_AssembleSbrBitstream *******************************/
170/**
171 * @fn
172 * @brief    Formats the SBR payload
173 * @return   nothing
174 *
175 * Also the CRC will be calculated here.
176 *
177 */
178
179void
180FDKsbrEnc_AssembleSbrBitstream( HANDLE_COMMON_DATA  hCmonData,
181                                HANDLE_FDK_CRCINFO  hCrcInfo,
182                                INT                 crcRegion,
183                                UINT                sbrSyntaxFlags)
184{
185  USHORT crcReg =  SBR_CRCINIT;
186  INT numCrcBits,i;
187
188  /* check if SBR is present */
189  if ( hCmonData==NULL )
190    return;
191
192  hCmonData->sbrFillBits = 0; /* Fill bits are written only for GA streams */
193
194  if ( sbrSyntaxFlags & SBR_SYNTAX_DRM_CRC )
195  {
196    /*
197     * Calculate and write DRM CRC
198     */
199    FDKcrcEndReg( hCrcInfo, &hCmonData->sbrBitbuf, crcRegion );
200    FDKwriteBits( &hCmonData->tmpWriteBitbuf, FDKcrcGetCRC(hCrcInfo)^0xFF, SI_SBR_DRM_CRC_BITS );
201  }
202  else
203  {
204    if ( !(sbrSyntaxFlags & SBR_SYNTAX_LOW_DELAY) )
205    {
206      /* Do alignment here, because its defined as part of the sbr_extension_data */
207      int sbrLoad = hCmonData->sbrHdrBits + hCmonData->sbrDataBits;
208
209      if ( sbrSyntaxFlags & SBR_SYNTAX_CRC ) {
210        sbrLoad += SI_SBR_CRC_BITS;
211      }
212
213      sbrLoad += 4;         /* Do byte Align with 4 bit offset. ISO/IEC 14496-3:2005(E) page 39. */
214
215      hCmonData->sbrFillBits = (8 - (sbrLoad % 8)) % 8;
216
217      /*
218        append fill bits
219      */
220      FDKwriteBits(&hCmonData->sbrBitbuf, 0,  hCmonData->sbrFillBits );
221
222      FDK_ASSERT(FDKgetValidBits(&hCmonData->sbrBitbuf) % 8 == 4);
223    }
224
225    /*
226      calculate crc
227    */
228    if ( sbrSyntaxFlags & SBR_SYNTAX_CRC ) {
229      FDK_BITSTREAM  tmpCRCBuf = hCmonData->sbrBitbuf;
230      FDKresetBitbuffer( &tmpCRCBuf, BS_READER );
231
232      numCrcBits = hCmonData->sbrHdrBits + hCmonData->sbrDataBits + hCmonData->sbrFillBits;
233
234      for(i=0;i<numCrcBits;i++){
235        INT bit;
236        bit = FDKreadBits(&tmpCRCBuf,1);
237        crcAdvance(SBR_CRC_POLY,SBR_CRC_MASK,&crcReg,bit,1);
238      }
239      crcReg &= (SBR_CRC_RANGE);
240
241      /*
242       * Write CRC data.
243       */
244      FDKwriteBits (&hCmonData->tmpWriteBitbuf, crcReg, SI_SBR_CRC_BITS);
245    }
246  }
247
248  FDKsyncCache(&hCmonData->tmpWriteBitbuf);
249}
250
251