1 /* ------------------------------------------------------------------ 2 * Copyright (C) 1998-2009 PacketVideo 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either 13 * express or implied. 14 * See the License for the specific language governing permissions 15 * and limitations under the License. 16 * ------------------------------------------------------------------- 17 */ 18 /**************************************************************************************** 19 Portions of this file are derived from the following 3GPP standard: 20 21 3GPP TS 26.073 22 ANSI-C code for the Adaptive Multi-Rate (AMR) speech codec 23 Available from http://www.3gpp.org 24 25 (C) 2004, 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TTA, TTC) 26 Permission to distribute, modify and use this file under the standard license 27 terms listed above has been obtained from the copyright holder. 28 ****************************************************************************************/ 29 /* 30 ------------------------------------------------------------------------------ 31 32 33 Pathname: ./audio/gsm-amr/c/src/amrdecode.c 34 35 Date: 05/23/2001 36 ------------------------------------------------------------------------------ 37 REVISION HISTORY 38 39 Description: AMRDecode now doesn't call getbits() or put_header_in(). 40 It also now obtains a new bit_offset value from a constant 41 rather than from the returned value of getbits(). 42 43 Description: AMRDecode now returns byte_offset rather than bit_offset, 44 so the program can access the next frame that is byte 45 aligned rather than packed without padding. 46 47 Description: The structure types Speech_Decode_FrameState are now 48 passed into amrdecode( ) using void pointers, so that 49 higher level functions don't need to know anything about 50 this structure type. 51 52 Description: Changed input argument list. Added code to handle incoming DTX 53 frames, and added call to wmf_to_ets function prior to calling 54 GSMFrameDecode. 55 56 Description: Made the following changes per comments from Phase 2/3 review: 57 1. Changed all references to bit_offset to byte_offset. 58 59 Description: Added input_type to the function interface and modified code 60 to check type of conversion that needs to be made. 61 62 Description: Modified pseudo-code to include IF2 and ETS input formats. 63 Removed byte_offset from input list. Renamed speech_bits 64 to speech_bits_ptr. 65 66 Description: Added dec_input_format_tab.h in Include section. Modified 67 pseudo-code to use correct table names. Renamed input_type to 68 input_format and speech_bits to speech_bits_ptr. 69 70 Description: Removed *prev_mode_ptr in the input argument list. 71 72 Description: Made the following changes per comments from Phase 2/3 review: 73 1. Removed dec_input_format_tab.h from Include section. 74 2. Changed type definition of raw_pcm_buffer in the I/O 75 definition section. 76 77 Description: Renamed WmfBytesPerFrame to WmfDecBytesPerFrame, and 78 If2BytesPerFrame to If2DecBytesPerFrame. 79 80 Description: Modified code so that the ETS testvectors could be fed directly 81 to this function. 82 83 Description: Changed '&' to '&&' in the setting of rx_type and mode for 84 AMR_SID < frame_type < NO_DATA case. 85 86 Description: Added code comments and made some code optimizations per Phase 87 2/3 review comments. 88 89 Description: Added conditional compile around the call to GSMFrameDecode to 90 allow amrdecode.c to be used in the ETS reference console. 91 92 Description: 93 94 ------------------------------------------------------------------------------ 95 */ 96 97 /*---------------------------------------------------------------------------- 98 ; INCLUDES 99 ----------------------------------------------------------------------------*/ 100 #include "amrdecode.h" 101 #include "cnst.h" 102 #include "typedef.h" 103 #include "frame.h" 104 #include "sp_dec.h" 105 #include "wmf_to_ets.h" 106 #include "if2_to_ets.h" 107 #include "frame_type_3gpp.h" 108 109 /*---------------------------------------------------------------------------- 110 ; MACROS 111 ; Define module specific macros here 112 ----------------------------------------------------------------------------*/ 113 114 115 /*---------------------------------------------------------------------------- 116 ; DEFINES 117 ; Include all pre-processor statements here. Include conditional 118 ; compile variables also. 119 ----------------------------------------------------------------------------*/ 120 121 122 /*---------------------------------------------------------------------------- 123 ; LOCAL FUNCTION DEFINITIONS 124 ; Function Prototype declaration 125 ----------------------------------------------------------------------------*/ 126 127 /*---------------------------------------------------------------------------- 128 ; LOCAL STORE/BUFFER/POINTER DEFINITIONS 129 ; Variable declaration - defined here and used outside this module 130 ----------------------------------------------------------------------------*/ 131 132 /* 133 ------------------------------------------------------------------------------ 134 FUNCTION NAME: AMRDecode 135 ------------------------------------------------------------------------------ 136 INPUT AND OUTPUT DEFINITIONS 137 138 Inputs: 139 state_data = pointer to a structure (type void) 140 141 frame_type = 3GPP frame type (enum Frame_Type_3GPP) 142 143 speech_bits_ptr = pointer to the beginning of the raw encoded speech bits 144 for the current frame to be decoded (unsigned char) 145 146 raw_pcm_buffer = pointer to the output pcm outputs array (Word16) 147 148 input_format = input format used; valid values are AMR_WMF, AMR_IF2, 149 and AMR_ETS (Word16) 150 151 Outputs: 152 raw_pcm_buffer contains the newly decoded linear PCM speech samples 153 state_data->prev_mode contains the new mode 154 155 Returns: 156 byte_offset = address offset of the next frame to be processed or 157 error condition flag (-1) (int) 158 159 Global Variables Used: 160 WmfDecBytesPerFrame = table containing the number of core AMR data bytes 161 used by each codec mode for WMF input format (const 162 int) 163 164 If2DecBytesPerFrame = table containing the number of core AMR data bytes 165 used by each codec mode for IF2 input format (const 166 int) 167 168 Local Variables Needed: 169 None 170 171 ------------------------------------------------------------------------------ 172 FUNCTION DESCRIPTION 173 174 This function is the top level entry function to the GSM AMR Decoder library. 175 176 First, it checks the input format type (input_format) to determine the type 177 of de-formattting that needs to be done. If input_format is AMR_WMF, the input 178 data is in WMF (aka, non-IF2) format and the function wmf_to_ets will be 179 called to convert to the ETS format (1 bit/word, where 1 word = 16 bits), 180 and byte_offset will be updated according to the contents of WmfDecBytesPerFrame 181 table. 182 183 If input_format is AMR_IF2, the input data is in IF2 format [1] and the 184 function if2_to_ets will be called to convert to the ETS format, and 185 byte_offset will be updated according to the contents of If2DecBytesPerFrame 186 table. 187 188 The codec mode and receive frame type is initialized based on the incoming 189 frame_type. 190 191 If input_format is AMR_ETS, the input data is in the ETS format. The receive 192 frame type is set to the value in the first location of the buffer pointed to 193 by speech_bits_ptr. Then, the encoded speech parameters in the buffer pointed 194 to by speech_bits is copied to dec_ets_input_bfr and the type will be changed 195 from unsigned char to Word16. Lastly, if the receive frame type is not 196 RX_NO_DATA, the mode is obtained from the buffer pointed to by 197 speech_bits_ptr, offset by MAX_SERIAL_SIZE+1, otherwise, the mode is set to 198 the previous mode (found the in state_data->prev_mode). 199 200 If input_format is an unsupported format, byte_offset will be set to -1, to 201 indicate an error condition has occurred, and the function will exit. 202 203 If there are no errors, GSMFrameDecode is called to decode a 20 ms frame. It 204 puts the decoded linear PCM samples in the buffer pointed to by 205 raw_pcm_buffer. Then, the prev_mode field of the structure pointed to by 206 state_data is updated to the current mode. 207 208 This function returns the new byte_offset value to indicate the address 209 offset of the next speech frame to be decoded. 210 211 ------------------------------------------------------------------------------ 212 REQUIREMENTS 213 214 None 215 216 ------------------------------------------------------------------------------ 217 REFERENCES 218 219 [1] "AMR Speech Codec Frame Structure", 3GPP TS 26.101 version 4.1.0 220 Release 4, June 2001 221 222 ------------------------------------------------------------------------------ 223 PSEUDO-CODE 224 225 Note: AMRSID_RXTYPE_BIT_OFFSET = 35 226 AMRSID_RXMODE_BIT_OFFSET = 36 227 NUM_AMRSID_RXMODE_BITS = 3 228 229 230 // Set up Decoder state structure pointer 231 Speech_Decode_FrameState *decoder_state 232 = (Speech_Decode_FrameState *) state_data 233 234 // Determine type of de-formatting 235 236 // Decode WMF or IF2 frames 237 IF ((input_format == AMR_RX_WMF) | (input_format == AMR_RX_IF2)) 238 THEN 239 IF (input_format == AMR_RX_WMF) 240 THEN 241 // Convert incoming packetized raw WMF data to ETS format 242 CALL wmf_to_ets(frame_type = frame_type 243 input_ptr = speech_bits_ptr 244 output_ptr = &dec_ets_input_bfr) 245 MODIFYING(nothing) 246 RETURNING(nothing) 247 248 // Address offset of the start of next frame 249 byte_offset = WmfDecBytesPerFrame[frame_type] 250 251 ELSEIF (input_format == AMR_RX_IF2) 252 THEN 253 // Convert incoming packetized raw IF2 data to ETS format 254 CALL if2_to_ets(frame_type = frame_type 255 input_ptr = speech_bits_ptr 256 output_ptr = &dec_ets_input_bfr) 257 MODIFYING(nothing) 258 RETURNING(nothing) 259 260 // Address offset of the start of next frame 261 byte_offset = If2DecBytesPerFrame[frame_type] 262 263 ENDIF 264 265 // Determine AMR codec mode and AMR RX frame type 266 IF (frame_type <= AMR_122) 267 THEN 268 mode = (enum Mode) frame_type; 269 rx_type = RX_SPEECH_GOOD; 270 271 ELSEIF (frame_type == AMR_SID) 272 THEN 273 // Clear mode store prior to reading mode info from input buffer 274 mode = 0 275 276 FOR i = 0 TO NUM_AMRSID_RXMODE_BITS-1 277 278 mode |= (dec_ets_input_bfr[AMRSID_RXMODE_BIT_OFFSET+i] << i) 279 280 ENDFOR 281 282 IF (dec_ets_input_bfr[AMRSID_RXTYPE_BIT_OFFSET] == 0) 283 THEN 284 rx_type = RX_SID_FIRST 285 286 ELSE 287 rx_type = RX_SID_UPDATE 288 289 ENDIF 290 291 ELSEIF ((frame_type > AMR_SID) && (frame_type < NO_DATA)) 292 THEN 293 // Use previous mode 294 mode = decoder_state->prev_mode 295 296 // Unsupported SID frames 297 rx_type = RX_SPEECH_BAD; 298 299 ELSE 300 // Use previous mode 301 mode = decoder_state->prev_mode 302 303 // No data received 304 rx_type = RX_NO_DATA; 305 306 ENDIF 307 308 // Decode ETS frames 309 ELSEIF (input_format == AMR_RX_ETS) 310 THEN 311 // Change type of pointer to incoming raw ETS data 312 ets_word_ptr = (Word16 *) speech_bits_ptr 313 314 // Get RX frame type 315 rx_type = (enum RXFrameType) *ets_word_ptr 316 ets_word_ptr = ets_word_ptr + 1 317 318 // Copy incoming raw ETS data to dec_ets_input_bfr 319 FOR i = 0 TO MAX_SERIAL_SIZE-1 320 321 dec_ets_input_bfr[i] = *ets_word_ptr 322 ets_word_ptr = ets_word_ptr + 1 323 324 ENDFOR 325 326 // Get codec mode 327 IF (rx_type != RX_NO_DATA) 328 THEN 329 mode = (enum Mode) *ets_word_ptr 330 331 ELSE 332 //Use previous mode if no received data 333 mode = decoder_state->prev_mode 334 335 ENDIF 336 337 // Set up byte_offset 338 byte_offset = 2*(MAX_SERIAL_SIZE+2) 339 340 ELSE 341 // Invalid format, return error code 342 byte_offset = -1 343 344 ENDIF 345 346 // Proceed with decoding frame, if there are no errors 347 IF (byte_offset != -1) 348 THEN 349 // Decode a 20 ms frame 350 CALL GSMFrameDecode( st = decoder_state 351 mode = mode 352 serial = dec_ets_input_bfr, 353 frame_type = rx_type, 354 synth = (Word16 *)raw_pcm_buffer); 355 MODIFYING (nothing) 356 RETURNING (Nothing) 357 358 // Save mode for next frame 359 decoder_state->prev_mode = mode 360 361 ENDIF 362 363 RETURN (byte_offset) 364 365 ------------------------------------------------------------------------------ 366 RESOURCES USED [optional] 367 368 When the code is written for a specific target processor the 369 the resources used should be documented below. 370 371 HEAP MEMORY USED: x bytes 372 373 STACK MEMORY USED: x bytes 374 375 CLOCK CYCLES: (cycle count equation for this function) + (variable 376 used to represent cycle count for each subroutine 377 called) 378 where: (cycle count variable) = cycle count for [subroutine 379 name] 380 381 ------------------------------------------------------------------------------ 382 CAUTION [optional] 383 [State any special notes, constraints or cautions for users of this function] 384 385 ------------------------------------------------------------------------------ 386 */ 387 388 Word16 AMRDecode( 389 void *state_data, 390 enum Frame_Type_3GPP frame_type, 391 UWord8 *speech_bits_ptr, 392 Word16 *raw_pcm_buffer, 393 bitstream_format input_format 394 ) 395 { 396 Word16 *ets_word_ptr; 397 enum Mode mode = (enum Mode)MR475; 398 int modeStore; 399 int tempInt; 400 enum RXFrameType rx_type = RX_NO_DATA; 401 Word16 dec_ets_input_bfr[MAX_SERIAL_SIZE]; 402 Word16 i; 403 Word16 byte_offset = -1; 404 405 /* Type cast state_data to Speech_Decode_FrameState rather than passing 406 * that structure type to this function so the structure make up can't 407 * be viewed from higher level functions than this. 408 */ 409 Speech_Decode_FrameState *decoder_state 410 = (Speech_Decode_FrameState *) state_data; 411 412 /* Determine type of de-formatting */ 413 /* WMF or IF2 frames */ 414 if ((input_format == MIME_IETF) | (input_format == IF2)) 415 { 416 if (input_format == MIME_IETF) 417 { 418 /* Convert incoming packetized raw WMF data to ETS format */ 419 wmf_to_ets(frame_type, speech_bits_ptr, dec_ets_input_bfr); 420 421 /* Address offset of the start of next frame */ 422 byte_offset = WmfDecBytesPerFrame[frame_type]; 423 } 424 else /* else has to be input_format IF2 */ 425 { 426 /* Convert incoming packetized raw IF2 data to ETS format */ 427 if2_to_ets(frame_type, speech_bits_ptr, dec_ets_input_bfr); 428 429 /* Address offset of the start of next frame */ 430 byte_offset = If2DecBytesPerFrame[frame_type]; 431 } 432 433 /* At this point, input data is in ETS format */ 434 /* Determine AMR codec mode and AMR RX frame type */ 435 if (frame_type <= AMR_122) 436 { 437 mode = (enum Mode) frame_type; 438 rx_type = RX_SPEECH_GOOD; 439 } 440 else if (frame_type == AMR_SID) 441 { 442 /* Clear mode store prior to reading mode info from input buffer */ 443 modeStore = 0; 444 445 for (i = 0; i < NUM_AMRSID_RXMODE_BITS; i++) 446 { 447 tempInt = dec_ets_input_bfr[AMRSID_RXMODE_BIT_OFFSET+i] << i; 448 modeStore |= tempInt; 449 } 450 mode = (enum Mode) modeStore; 451 452 /* Get RX frame type */ 453 if (dec_ets_input_bfr[AMRSID_RXTYPE_BIT_OFFSET] == 0) 454 { 455 rx_type = RX_SID_FIRST; 456 } 457 else 458 { 459 rx_type = RX_SID_UPDATE; 460 } 461 } 462 else if (frame_type < AMR_NO_DATA) 463 { 464 /* Invalid frame_type, return error code */ 465 byte_offset = -1; /* !!! */ 466 } 467 else 468 { 469 mode = decoder_state->prev_mode; 470 471 /* 472 * RX_NO_DATA, generate exponential decay from latest valid frame for the first 6 frames 473 * after that, create silent frames 474 */ 475 rx_type = RX_NO_DATA; 476 477 } 478 479 } 480 481 /* ETS frames */ 482 else if (input_format == ETS) 483 { 484 /* Change type of pointer to incoming raw ETS data */ 485 ets_word_ptr = (Word16 *) speech_bits_ptr; 486 487 /* Get RX frame type */ 488 rx_type = (enum RXFrameType) * ets_word_ptr; 489 ets_word_ptr++; 490 491 /* Copy incoming raw ETS data to dec_ets_input_bfr */ 492 for (i = 0; i < MAX_SERIAL_SIZE; i++) 493 { 494 dec_ets_input_bfr[i] = *ets_word_ptr; 495 ets_word_ptr++; 496 } 497 498 /* Get codec mode */ 499 if (rx_type != RX_NO_DATA) 500 { 501 /* Get mode from input bitstream */ 502 mode = (enum Mode) * ets_word_ptr; 503 } 504 else 505 { 506 /* Use previous mode if no received data */ 507 mode = decoder_state->prev_mode; 508 } 509 510 /* Set up byte_offset */ 511 byte_offset = 2 * (MAX_SERIAL_SIZE + 2); 512 } 513 else 514 { 515 /* Invalid input format, return error code */ 516 byte_offset = -1; 517 } 518 519 /* Proceed with decoding frame, if there are no errors */ 520 if (byte_offset != -1) 521 { 522 /* Decode a 20 ms frame */ 523 524 #ifndef CONSOLE_DECODER_REF 525 /* Use PV version of sp_dec.c */ 526 GSMFrameDecode(decoder_state, mode, dec_ets_input_bfr, rx_type, 527 raw_pcm_buffer); 528 529 #else 530 /* Use ETS version of sp_dec.c */ 531 Speech_Decode_Frame(decoder_state, mode, dec_ets_input_bfr, rx_type, 532 raw_pcm_buffer); 533 534 #endif 535 536 /* Save mode for next frame */ 537 decoder_state->prev_mode = mode; 538 } 539 540 return (byte_offset); 541 } 542 543 544 545
