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/***************************** MPEG-4 AAC Decoder ************************** 85 86 Author(s): Josef Hoepfl 87 Description: ADTS interface 88 89******************************************************************************/ 90 91#include "tpdec_adts.h" 92 93 94#include "FDK_bitstream.h" 95 96 97 98void adtsRead_CrcInit(HANDLE_ADTS pAdts) /*!< pointer to adts crc info stucture */ 99{ 100 FDKcrcInit(&pAdts->crcInfo, 0x8005, 0xFFFF, 16); 101} 102 103int adtsRead_CrcStartReg( 104 HANDLE_ADTS pAdts, /*!< pointer to adts stucture */ 105 HANDLE_FDK_BITSTREAM hBs, /*!< handle to current bit buffer structure */ 106 int mBits /*!< number of bits in crc region */ 107 ) 108{ 109 if (pAdts->bs.protection_absent) { 110 return 0; 111 } 112 113 return ( FDKcrcStartReg(&pAdts->crcInfo, hBs, mBits) ); 114 115} 116 117void adtsRead_CrcEndReg( 118 HANDLE_ADTS pAdts, /*!< pointer to adts crc info stucture */ 119 HANDLE_FDK_BITSTREAM hBs, /*!< handle to current bit buffer structure */ 120 int reg /*!< crc region */ 121 ) 122{ 123 if (pAdts->bs.protection_absent == 0) 124 { 125 FDKcrcEndReg(&pAdts->crcInfo, hBs, reg); 126 } 127} 128 129TRANSPORTDEC_ERROR adtsRead_CrcCheck( HANDLE_ADTS pAdts ) 130{ 131 TRANSPORTDEC_ERROR ErrorStatus = TRANSPORTDEC_OK; 132 USHORT crc; 133 134 if (pAdts->bs.protection_absent) 135 return TRANSPORTDEC_OK; 136 137 crc = FDKcrcGetCRC(&pAdts->crcInfo); 138 if (crc != pAdts->crcReadValue) 139 { 140 return (TRANSPORTDEC_CRC_ERROR); 141 } 142 143 return (ErrorStatus); 144} 145 146 147 148#define Adts_Length_SyncWord 12 149#define Adts_Length_Id 1 150#define Adts_Length_Layer 2 151#define Adts_Length_ProtectionAbsent 1 152#define Adts_Length_Profile 2 153#define Adts_Length_SamplingFrequencyIndex 4 154#define Adts_Length_PrivateBit 1 155#define Adts_Length_ChannelConfiguration 3 156#define Adts_Length_OriginalCopy 1 157#define Adts_Length_Home 1 158#define Adts_Length_CopyrightIdentificationBit 1 159#define Adts_Length_CopyrightIdentificationStart 1 160#define Adts_Length_FrameLength 13 161#define Adts_Length_BufferFullness 11 162#define Adts_Length_NumberOfRawDataBlocksInFrame 2 163#define Adts_Length_CrcCheck 16 164 165TRANSPORTDEC_ERROR adtsRead_DecodeHeader( 166 HANDLE_ADTS pAdts, 167 CSAudioSpecificConfig *pAsc, 168 HANDLE_FDK_BITSTREAM hBs, 169 const INT ignoreBufferFullness 170 ) 171{ 172 INT crcReg; 173 174 INT valBits; 175 INT cmp_buffer_fullness; 176 int i, adtsHeaderLength; 177 178 STRUCT_ADTS_BS bs; 179 180#ifdef TP_PCE_ENABLE 181 CProgramConfig oldPce; 182 /* Store the old PCE temporarily. Maybe we'll need it later if we 183 have channelConfig=0 and no PCE in this frame. */ 184 FDKmemcpy(&oldPce, &pAsc->m_progrConfigElement, sizeof(CProgramConfig)); 185#endif 186 187 valBits = FDKgetValidBits(hBs); 188 189 /* adts_fixed_header */ 190 bs.mpeg_id = FDKreadBits(hBs, Adts_Length_Id); 191 bs.layer = FDKreadBits(hBs, Adts_Length_Layer); 192 bs.protection_absent = FDKreadBits(hBs, Adts_Length_ProtectionAbsent); 193 bs.profile = FDKreadBits(hBs, Adts_Length_Profile); 194 bs.sample_freq_index = FDKreadBits(hBs, Adts_Length_SamplingFrequencyIndex); 195 bs.private_bit = FDKreadBits(hBs, Adts_Length_PrivateBit); 196 bs.channel_config = FDKreadBits(hBs, Adts_Length_ChannelConfiguration); 197 bs.original = FDKreadBits(hBs, Adts_Length_OriginalCopy); 198 bs.home = FDKreadBits(hBs, Adts_Length_Home); 199 200 /* adts_variable_header */ 201 bs.copyright_id = FDKreadBits(hBs, Adts_Length_CopyrightIdentificationBit); 202 bs.copyright_start = FDKreadBits(hBs, Adts_Length_CopyrightIdentificationStart); 203 bs.frame_length = FDKreadBits(hBs, Adts_Length_FrameLength); 204 bs.adts_fullness = FDKreadBits(hBs, Adts_Length_BufferFullness); 205 bs.num_raw_blocks = FDKreadBits(hBs, Adts_Length_NumberOfRawDataBlocksInFrame); 206 bs.num_pce_bits = 0; 207 208 adtsHeaderLength = ADTS_HEADERLENGTH; 209 210 if (!bs.protection_absent) { 211 FDKcrcReset(&pAdts->crcInfo); 212 FDKpushBack(hBs, 56); /* complete fixed and variable header! */ 213 crcReg = FDKcrcStartReg(&pAdts->crcInfo, hBs, 0); 214 FDKpushFor(hBs, 56); 215 } 216 217 if (! bs.protection_absent && bs.num_raw_blocks>0) { 218 for (i=0; i<bs.num_raw_blocks; i++) { 219 pAdts->rawDataBlockDist[i] = (USHORT)FDKreadBits(hBs, 16); 220 adtsHeaderLength += 16; 221 } 222 /* Change raw data blocks to delta values */ 223 pAdts->rawDataBlockDist[bs.num_raw_blocks] = bs.frame_length - 7 - bs.num_raw_blocks*2 - 2 ; 224 for (i=bs.num_raw_blocks; i>0; i--) { 225 pAdts->rawDataBlockDist[i] -= pAdts->rawDataBlockDist[i-1]; 226 } 227 } 228 229 /* adts_error_check */ 230 if (!bs.protection_absent) 231 { 232 USHORT crc_check; 233 234 FDKcrcEndReg(&pAdts->crcInfo, hBs, crcReg); 235 crc_check = FDKreadBits(hBs, Adts_Length_CrcCheck); 236 adtsHeaderLength += Adts_Length_CrcCheck; 237 238 pAdts->crcReadValue = crc_check; 239 /* Check header CRC in case of multiple raw data blocks */ 240 if (bs.num_raw_blocks > 0) { 241 if (pAdts->crcReadValue != FDKcrcGetCRC(&pAdts->crcInfo)) { 242 return TRANSPORTDEC_CRC_ERROR; 243 } 244 /* Reset CRC for the upcoming raw_data_block() */ 245 FDKcrcReset(&pAdts->crcInfo); 246 } 247 } 248 249 250 /* check if valid header */ 251 if ( 252 (bs.layer != 0) || // we only support MPEG ADTS 253 (bs.sample_freq_index >= 13) // we only support 96kHz - 7350kHz 254 ) { 255 FDKpushFor(hBs, bs.frame_length * 8); // try again one frame later 256 return TRANSPORTDEC_UNSUPPORTED_FORMAT; 257 } 258 259 /* special treatment of id-bit */ 260 if ( (bs.mpeg_id == 0) && (pAdts->decoderCanDoMpeg4 == 0) ) 261 { 262 /* MPEG-2 decoder cannot play MPEG-4 bitstreams */ 263 264 265 FDKpushFor(hBs, bs.frame_length * 8); // try again one frame later 266 return TRANSPORTDEC_UNSUPPORTED_FORMAT; 267 } 268 269 if (!ignoreBufferFullness) 270 { 271 cmp_buffer_fullness = bs.frame_length*8 + bs.adts_fullness*32*getNumberOfEffectiveChannels(bs.channel_config); 272 273 274 /* Evaluate buffer fullness */ 275 if (bs.adts_fullness != 0x7FF) 276 { 277 if (pAdts->BufferFullnesStartFlag) 278 { 279 if ( valBits < cmp_buffer_fullness ) 280 { 281 /* Condition for start of decoding is not fulfilled */ 282 283 /* The current frame will not be decoded */ 284 FDKpushBack(hBs, adtsHeaderLength); 285 286 if ( (cmp_buffer_fullness+adtsHeaderLength) > ((TRANSPORTDEC_INBUF_SIZE<<3)-7) ) { 287 return TRANSPORTDEC_SYNC_ERROR; 288 } else { 289 return TRANSPORTDEC_NOT_ENOUGH_BITS; 290 } 291 } 292 else 293 { 294 pAdts->BufferFullnesStartFlag = 0; 295 } 296 } 297 } 298 } 299 300 301 /* Get info from ADTS header */ 302 AudioSpecificConfig_Init(pAsc); 303 pAsc->m_aot = (AUDIO_OBJECT_TYPE)(bs.profile + 1); 304 pAsc->m_samplingFrequencyIndex = bs.sample_freq_index; 305 pAsc->m_samplingFrequency = SamplingRateTable[bs.sample_freq_index]; 306 pAsc->m_channelConfiguration = bs.channel_config; 307 pAsc->m_samplesPerFrame = 1024; 308 309#ifdef TP_PCE_ENABLE 310 if (bs.channel_config == 0) 311 { 312 int pceBits = 0; 313 UINT alignAnchor = FDKgetValidBits(hBs); 314 315 if (FDKreadBits(hBs,3) == ID_PCE) { 316 /* Got luck! Parse the PCE */ 317 int crcReg; 318 crcReg = adtsRead_CrcStartReg(pAdts, hBs, 0); 319 320 CProgramConfig_Read(&pAsc->m_progrConfigElement, hBs, alignAnchor); 321 322 adtsRead_CrcEndReg(pAdts, hBs, crcReg); 323 pceBits = alignAnchor - FDKgetValidBits(hBs); 324 /* store the number of PCE bits */ 325 bs.num_pce_bits = pceBits; 326 } 327 else { 328 /* No PCE in this frame! Push back the ID tag bits. */ 329 FDKpushBack(hBs,3); 330 331 /* Encoders do not have to write a PCE in each frame. 332 So if we already have a valid PCE we have to use it. */ 333 if ( oldPce.isValid 334 && (bs.sample_freq_index == pAdts->bs.sample_freq_index) /* we could compare the complete fixed header (bytes) here! */ 335 && (bs.channel_config == pAdts->bs.channel_config) /* == 0 */ 336 && (bs.mpeg_id == pAdts->bs.mpeg_id) ) 337 { /* Restore previous PCE which is still valid */ 338 FDKmemcpy(&pAsc->m_progrConfigElement, &oldPce, sizeof(CProgramConfig)); 339 } 340 else if (bs.mpeg_id == 0) { 341 /* If not it seems that we have a implicit channel configuration. 342 This mode is not allowed in the context of ISO/IEC 14496-3. 343 Skip this frame and try the next one. */ 344 FDKpushFor(hBs, (bs.frame_length<<3) - adtsHeaderLength - 3); 345 return TRANSPORTDEC_UNSUPPORTED_FORMAT; 346 } 347 /* else { 348 ISO/IEC 13818-7 implicit channel mapping is allowed. 349 So just open the box of chocolates to see what we got. 350 } */ 351 } 352 } 353#endif /* TP_PCE_ENABLE */ 354 355 /* Copy bit stream data struct to persistent memory now, once we passed all sanity checks above. */ 356 FDKmemcpy(&pAdts->bs, &bs, sizeof(STRUCT_ADTS_BS)); 357 358 return TRANSPORTDEC_OK; 359} 360 361int adtsRead_GetRawDataBlockLength( 362 HANDLE_ADTS pAdts, 363 INT blockNum 364 ) 365{ 366 int length; 367 368 if (pAdts->bs.num_raw_blocks == 0) { 369 length = (pAdts->bs.frame_length - 7) << 3; /* aac_frame_length subtracted by the header size (7 bytes). */ 370 if (pAdts->bs.protection_absent == 0) 371 length -= 16; /* substract 16 bit CRC */ 372 } else { 373 if (pAdts->bs.protection_absent) { 374 length = -1; /* raw data block length is unknown */ 375 } else { 376 if (blockNum < 0 || blockNum > 3) { 377 length = -1; 378 } 379 length = (pAdts->rawDataBlockDist[blockNum] << 3) - 16; 380 } 381 } 382 if (blockNum == 0 && length > 0) { 383 length -= pAdts->bs.num_pce_bits; 384 } 385 return length; 386} 387 388 389