tpenc_adts.cpp revision 2228e360595641dd906bf1773307f43d304f5b2e 
1
2/* -----------------------------------------------------------------------------------------------------------
3Software License for The Fraunhofer FDK AAC Codec Library for Android
4
5� Copyright  1995 - 2012 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:
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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.
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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.
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45You may not charge copyright license fees for anyone to use, copy or distribute the FDK AAC Codec
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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."
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533.    NO PATENT LICENSE
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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.
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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
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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/******************************** 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
98int 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
110void 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
122int 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
148INT 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
187int 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
255void 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