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 /******************************** MPEG Audio Encoder **************************
85 
86    Initial author:       Alex Groeschel
87    contents/description: ADTS Transport Headers support
88 
89 ******************************************************************************/
90 
91 #include "tpenc_adts.h"
92 
93 
94 #include "tpenc_lib.h"
95 #include "tpenc_asc.h"
96 
97 
adtsWrite_CrcStartReg(HANDLE_ADTS pAdts,HANDLE_FDK_BITSTREAM hBs,int mBits)98 int adtsWrite_CrcStartReg(
99                                  HANDLE_ADTS pAdts,          /*!< pointer to adts stucture */
100                                  HANDLE_FDK_BITSTREAM hBs,   /*!< handle to current bit buffer structure */
101                                  int mBits                   /*!< number of bits in crc region */
102                                 )
103 {
104   if (pAdts->protection_absent) {
105     return 0;
106   }
107   return ( FDKcrcStartReg(&pAdts->crcInfo, hBs, mBits) );
108 }
109 
adtsWrite_CrcEndReg(HANDLE_ADTS pAdts,HANDLE_FDK_BITSTREAM hBs,int reg)110 void adtsWrite_CrcEndReg(
111                                 HANDLE_ADTS pAdts, /*!< pointer to adts crc info stucture */
112                                 HANDLE_FDK_BITSTREAM hBs,   /*!< handle to current bit buffer structure */
113                                 int reg                    /*!< crc region */
114                                )
115 {
116   if (pAdts->protection_absent == 0)
117   {
118     FDKcrcEndReg(&pAdts->crcInfo, hBs, reg);
119   }
120 }
121 
adtsWrite_GetHeaderBits(HANDLE_ADTS hAdts)122 int adtsWrite_GetHeaderBits( HANDLE_ADTS hAdts )
123 {
124   int bits = 0;
125 
126   if (hAdts->currentBlock == 0) {
127     /* Static and variable header bits */
128     bits = 56;
129     if (!hAdts->protection_absent) {
130       /* Add header/ single raw data block CRC bits */
131       bits += 16;
132       if (hAdts->num_raw_blocks>0) {
133         /* Add bits of raw data block position markers */
134         bits += (hAdts->num_raw_blocks)*16;
135       }
136     }
137   }
138   if (!hAdts->protection_absent && hAdts->num_raw_blocks>0) {
139     /* Add raw data block CRC bits. Not really part of the header, put they cause bit overhead to be accounted. */
140     bits += 16;
141   }
142 
143   hAdts->headerBits = bits;
144 
145   return bits;
146 }
147 
adtsWrite_Init(HANDLE_ADTS hAdts,CODER_CONFIG * config)148 INT adtsWrite_Init(HANDLE_ADTS hAdts, CODER_CONFIG *config)
149 {
150   /* Sanity checks */
151   if ( config->nSubFrames < 1
152     || config->nSubFrames > 4
153     || (int)config->aot > 4
154     || (int)config->aot < 1 ) {
155     return -1;
156   }
157 
158   /* fixed header */
159   if (config->flags & CC_MPEG_ID) {
160     hAdts->mpeg_id = 0; /* MPEG 4 */
161   } else {
162     hAdts->mpeg_id = 1; /* MPEG 2 */
163   }
164   hAdts->layer=0;
165   hAdts->protection_absent = ! (config->flags & CC_PROTECTION);
166   hAdts->profile = ((int)config->aot) - 1;
167   hAdts->sample_freq_index = getSamplingRateIndex(config->samplingRate);
168   hAdts->sample_freq = config->samplingRate;
169   hAdts->private_bit=0;
170   hAdts->channel_mode = config->channelMode;
171   hAdts->original=0;
172   hAdts->home=0;
173   /* variable header */
174   hAdts->copyright_id=0;
175   hAdts->copyright_start=0;
176 
177   hAdts->num_raw_blocks=config->nSubFrames-1; /* 0 means 1 raw data block */
178 
179   FDKcrcInit(&hAdts->crcInfo, 0x8005, 0xFFFF, 16);
180 
181   hAdts->currentBlock = 0;
182 
183 
184   return 0;
185 }
186 
adtsWrite_EncodeHeader(HANDLE_ADTS hAdts,HANDLE_FDK_BITSTREAM hBitStream,int buffer_fullness,int frame_length)187 int adtsWrite_EncodeHeader(HANDLE_ADTS hAdts,
188                                  HANDLE_FDK_BITSTREAM hBitStream,
189                                  int buffer_fullness,
190                                  int frame_length)
191 {
192   INT crcIndex = 0;
193 
194 
195   hAdts->headerBits = adtsWrite_GetHeaderBits(hAdts);
196 
197   FDK_ASSERT(((frame_length+hAdts->headerBits)/8)<0x2000);      /*13 bit*/
198   FDK_ASSERT(buffer_fullness<0x800);    /* 11 bit   */
199 
200   if (!hAdts->protection_absent) {
201     FDKcrcReset(&hAdts->crcInfo);
202   }
203 
204   if (hAdts->currentBlock == 0) {
205     FDKresetBitbuffer(hBitStream, BS_WRITER);
206   }
207 
208   hAdts->subFrameStartBit = FDKgetValidBits(hBitStream);
209 
210   /* Skip new header if this is raw data block 1..n */
211   if (hAdts->currentBlock == 0)
212   {
213     FDKresetBitbuffer(hBitStream, BS_WRITER);
214 
215     if (hAdts->num_raw_blocks == 0) {
216       crcIndex = adtsWrite_CrcStartReg(hAdts, hBitStream, 0);
217     }
218 
219     /* fixed header */
220     FDKwriteBits(hBitStream, 0xFFF, 12);
221     FDKwriteBits(hBitStream, hAdts->mpeg_id, 1);
222     FDKwriteBits(hBitStream, hAdts->layer, 2);
223     FDKwriteBits(hBitStream, hAdts->protection_absent, 1);
224     FDKwriteBits(hBitStream, hAdts->profile, 2);
225     FDKwriteBits(hBitStream, hAdts->sample_freq_index, 4);
226     FDKwriteBits(hBitStream, hAdts->private_bit, 1);
227     FDKwriteBits(hBitStream, getChannelConfig(hAdts->channel_mode), 3);
228     FDKwriteBits(hBitStream, hAdts->original, 1);
229     FDKwriteBits(hBitStream, hAdts->home, 1);
230     /* variable header */
231     FDKwriteBits(hBitStream, hAdts->copyright_id, 1);
232     FDKwriteBits(hBitStream, hAdts->copyright_start, 1);
233     FDKwriteBits(hBitStream, (frame_length + hAdts->headerBits)>>3, 13);
234     FDKwriteBits(hBitStream, buffer_fullness, 11);
235     FDKwriteBits(hBitStream, hAdts->num_raw_blocks, 2);
236 
237     if (!hAdts->protection_absent) {
238       int i;
239 
240       /* End header CRC portion for single raw data block and write dummy zero values for unknown fields. */
241       if (hAdts->num_raw_blocks == 0) {
242         adtsWrite_CrcEndReg(hAdts, hBitStream, crcIndex);
243       } else {
244         for (i=0; i<hAdts->num_raw_blocks; i++) {
245           FDKwriteBits(hBitStream, 0, 16);
246         }
247       }
248       FDKwriteBits(hBitStream, 0, 16);
249     }
250   } /* End of ADTS header */
251 
252   return 0;
253 }
254 
adtsWrite_EndRawDataBlock(HANDLE_ADTS hAdts,HANDLE_FDK_BITSTREAM hBs,int * pBits)255 void adtsWrite_EndRawDataBlock(HANDLE_ADTS hAdts,
256                           HANDLE_FDK_BITSTREAM hBs,
257                           int *pBits)
258 {
259   if (!hAdts->protection_absent) {
260     FDK_BITSTREAM bsWriter;
261 
262     FDKinitBitStream(&bsWriter, hBs->hBitBuf.Buffer, hBs->hBitBuf.bufSize, 0, BS_WRITER);
263     FDKpushFor(&bsWriter, 56);
264 
265     if (hAdts->num_raw_blocks == 0) {
266       FDKwriteBits(&bsWriter, FDKcrcGetCRC(&hAdts->crcInfo), 16);
267     } else {
268       int distance;
269 
270       /* Write CRC of current raw data block */
271       FDKwriteBits(hBs, FDKcrcGetCRC(&hAdts->crcInfo), 16);
272 
273       /* Write distance to current data block */
274       if (hAdts->currentBlock < hAdts->num_raw_blocks) {
275         FDKpushFor(&bsWriter, hAdts->currentBlock*16);
276         distance = FDKgetValidBits(hBs) - (56 + (hAdts->num_raw_blocks)*16 + 16);
277         FDKwriteBits(&bsWriter, distance>>3, 16);
278       }
279     }
280     FDKsyncCache(&bsWriter);
281   }
282 
283   /* Write total frame lenth for multiple raw data blocks and header CRC */
284   if (hAdts->num_raw_blocks > 0 && hAdts->currentBlock == hAdts->num_raw_blocks) {
285     FDK_BITSTREAM bsWriter;
286     int crcIndex = 0;
287 
288     FDKinitBitStream(&bsWriter, hBs->hBitBuf.Buffer, hBs->hBitBuf.bufSize, 0, BS_WRITER);
289 
290     if (!hAdts->protection_absent) {
291       FDKcrcReset(&hAdts->crcInfo);
292       crcIndex = FDKcrcStartReg(&hAdts->crcInfo, &bsWriter, 0);
293     }
294     /* Write total frame length */
295     FDKpushFor(&bsWriter, 56-28+2);
296     FDKwriteBits(&bsWriter, FDKgetValidBits(hBs)>>3, 13);
297 
298     /* Write header CRC */
299     if (!hAdts->protection_absent) {
300       FDKpushFor(&bsWriter, 11+2 + (hAdts->num_raw_blocks)*16);
301       FDKcrcEndReg(&hAdts->crcInfo, &bsWriter, crcIndex);
302       FDKwriteBits(&bsWriter, FDKcrcGetCRC(&hAdts->crcInfo), 16);
303     }
304     FDKsyncCache(&bsWriter);
305   }
306 
307   /* Correct *pBits to reflect the amount of bits of the current subframe */
308   *pBits -= hAdts->subFrameStartBit;
309   if (!hAdts->protection_absent && hAdts->num_raw_blocks > 0) {
310     /* Fixup CRC bits, since they come after each raw data block */
311     *pBits += 16;
312   }
313   hAdts->currentBlock++;
314 }
315 
316