1 
2 /* -----------------------------------------------------------------------------------------------------------
3 Software 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
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  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  */
crcAdvance(USHORT crcPoly,USHORT crcMask,USHORT * crc,ULONG bValue,INT bBits)110 static 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 
FDKsbrEnc_InitSbrBitstream(HANDLE_COMMON_DATA hCmonData,UCHAR * memoryBase,INT memorySize,HANDLE_FDK_CRCINFO hCrcInfo,UINT sbrSyntaxFlags)140 INT  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 
179 void
FDKsbrEnc_AssembleSbrBitstream(HANDLE_COMMON_DATA hCmonData,HANDLE_FDK_CRCINFO hCrcInfo,INT crcRegion,UINT sbrSyntaxFlags)180 FDKsbrEnc_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