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 20 Pathname: huffdecode.c 21 22 ------------------------------------------------------------------------------ 23 REVISION HISTORY 24 25 Description: Modified from original shareware code 26 27 Description: Modified to pass variables by reference to eliminate use 28 of global variables. 29 30 Description: Change variable types. 31 32 Description: (1) Modified to bring in-line with PV standards. 33 (2) Eliminated global_gain on stack, 34 getics() has to define this parameter on its stack. 35 (3) Eliminated multiple returns 36 (4) Altered return logic of getics() 37 (5) Convert Real coef -> Int32 coef 38 (6) Move BITS *pInputStream to 2nd parameter of huffdecode.c 39 and getics.c 40 (7) Pass pFrameInfo per channel, because two channels can have 41 different windows 42 43 Description: (1) Eliminated function call to chn_config 44 (2) Eliminate widx calculation 45 (3) copy channel info from left to right when common_window 46 is enabled 47 (4) add error checking of getmask return value 48 49 Description: Change default_position to current_program 50 51 Description: Remove prstflag 52 53 Description: Modify call to get_ics_info 54 55 Description: Modified so getmask is NOT called if the status returned 56 from get_ics_info indicates an error. 57 58 Description: 59 (1) Added include of "e_ElementId.h" 60 Previously, this function was relying on another include file 61 to include e_ElementId.h 62 63 (2) Updated the copyright header. 64 65 Description: Modified to include usage of the new "shared memory" structures 66 defined in s_tDec_Int_File.h and s_tDec_Int_Chan.h 67 68 Description: 69 (1) Updated to reflect the fact that the temporary FrameInfo used by getics.c 70 was moved into the region of memory shared with fxpCoef. 71 72 Description: 73 (1) Removed first parameter to getics. The temporary FrameInfo was 74 unnecessary. 75 76 Description: Replace some instances of getbits to get9_n_lessbits 77 when the number of bits read is 9 or less and get1bits 78 when only 1 bit is read. 79 80 Description: Relaxed tag verification. Some encoder do not match the tag 81 to the channel ID (as the standard request to differentiate 82 different channel), in our wireless work, with only mono 83 or stereo channel, this become restrictive to some encoders 84 85 86 Description: 87 88 ------------------------------------------------------------------------------ 89 INPUT AND OUTPUT DEFINITIONS 90 91 Inputs: 92 93 id_syn_ele = identification flag for channel syntactic element, Int 94 95 pInputStream= pointer to input bitstream, BITS. 96 97 pVars = pointer to structure that holds information for decoding, 98 tDec_Int_File 99 100 pChVars[] = pointer to structure that holds channel information, 101 tDec_Int_Chan 102 103 104 Local Stores/Buffers/Pointers Needed: 105 None 106 107 Global Stores/Buffers/Pointers Needed: 108 None 109 110 Outputs: 111 status = 0 if success 112 non-zero otherwise 113 114 Pointers and Buffers Modified: 115 pChVars->sect contents updated by newly decoded section information 116 of current frame 117 118 pChVars->factors contents updated by newly decoded scalefactors 119 120 pChVars->ch_coef contents updated by newly decoded spectral coefficients 121 122 PChVars->tns contents updated by newly decoded TNS information 123 124 pVars->hasmask contents updated by newly decoded Mid/Side mask 125 information 126 127 pVars->pulseInfo contents updated by newly decoded pulse data information 128 129 Local Stores Modified: 130 None 131 132 Global Stores Modified: 133 None 134 135 ------------------------------------------------------------------------------ 136 FUNCTION DESCRIPTION 137 138 This function offers a framework for decoding the data of the next 1024 139 samples. It maps the channel configuration according to the id_syn_ele flag, 140 configures the channel information, and calls getics to do huffman decoding 141 The function returns 1 if there was an error 142 143 ------------------------------------------------------------------------------ 144 REQUIREMENTS 145 146 This function should set up the channel configuration for huffman decoding 147 148 ------------------------------------------------------------------------------ 149 REFERENCES 150 151 (1) MPEG-2 NBC Audio Decoder 152 "This software module was originally developed by AT&T, Dolby 153 Laboratories, Fraunhofer Gesellschaft IIS in the course of development 154 of the MPEG-2 NBC/MPEG-4 Audio standard ISO/IEC 13818-7, 14496-1,2 and 155 3. This software module is an implementation of a part of one or more 156 MPEG-2 NBC/MPEG-4 Audio tools as specified by the MPEG-2 NBC/MPEG-4 157 Audio standard. ISO/IEC gives users of the MPEG-2 NBC/MPEG-4 Audio 158 standards free license to this software module or modifications thereof 159 for use in hardware or software products claiming conformance to the 160 MPEG-2 NBC/MPEG-4 Audio standards. Those intending to use this software 161 module in hardware or software products are advised that this use may 162 infringe existing patents. The original developer of this software 163 module and his/her company, the subsequent editors and their companies, 164 and ISO/IEC have no liability for use of this software module or 165 modifications thereof in an implementation. Copyright is not released 166 for non MPEG-2 NBC/MPEG-4 Audio conforming products.The original 167 developer retains full right to use the code for his/her own purpose, 168 assign or donate the code to a third party and to inhibit third party 169 from using the code for non MPEG-2 NBC/MPEG-4 Audio conforming products. 170 This copyright notice must be included in all copies or derivative 171 works." 172 Copyright(c)1996. 173 174 (2) ISO/IEC 14496-3: 1999(E) 175 Subpart 4 p15 (single_channel_element, channel_pair_element) 176 p15 (Table 4.4.5 getmask) 177 p16 (Table 4.4.6 get_ics_info) 178 p24 (Table 4.4.24 getics) 179 180 ------------------------------------------------------------------------------ 181 PSEUDO-CODE 182 183 tag = CALL getbits(LEN_TAG,pInputStream) 184 MODIFYING(pInputStream) 185 RETURNING(tag) 186 187 common_window = 0; 188 189 IF (id_syn_ele == ID_CPE) 190 THEN 191 common_window = CALL getbits(LEN_COM_WIN,pInputStream); 192 MODIFYING(pInputStream) 193 RETURNING(common_window) 194 ENDIF 195 196 pMcInfo = &pVars->mc_info; 197 198 IF ( (pMcInfo->ch_info[0].cpe != id_syn_ele) OR 199 (pMcInfo->ch_info[0].tag != tag) ) 200 THEN 201 status = 1; 202 ENDIF 203 204 205 IF (status == SUCCESS) 206 THEN 207 IF (id_syn_ele == ID_SCE) 208 THEN 209 210 leftCh = 0; 211 RIGHT = 0; 212 pChVars[leftCh]->hasmask = 0; 213 ELSEIF (id_syn_ele == ID_CPE) 214 215 leftCh = 0; 216 rightCh = 1; 217 218 IF (common_window != FALSE) 219 THEN 220 221 CALL get_ics_info( 222 audioObjectType = pVars->mc_info.audioObjectType, 223 pInputStream = pInputStream, 224 common_window = common_window, 225 pWindowSequence = &pChVars[leftCh]->wnd, 226 &pChVars[leftCh]->wnd_shape_this_bk, 227 pChVars[leftCh]->group, 228 &pChVars[leftCh]->max_sfb, 229 pVars->winmap, 230 &pChVars[leftCh]->lt_status, 231 &pChVars[rightCh]->lt_status); 232 MODIFYING(pInputStream, wnd, wnd_shape_this_bk,group, 233 max_sfb, lt_status) 234 RETURNING(status) 235 236 IF (status == SUCCESS) 237 THEN 238 239 pChVars[rightCh]->wnd = pChVars[leftCh]->wnd; 240 pChVars[rightCh]->wnd_shape_this_bk = 241 pChVars[leftCh]->wnd_shape_this_bk; 242 pChVars[rightCh]->max_sfb = pChVars[leftCh]->max_sfb; 243 pv_memcpy( 244 pChVars[rightCh]->group, 245 pChVars[leftCh]->group, 246 NSHORT*sizeof(pChVars[leftCh]->group[0])); 247 248 hasmask = CALL getmask( 249 pVars->winmap[pChVars[leftCh]->wnd], 250 pInputStream, 251 pChVars[leftCh]->group, 252 pChVars[leftCh]->max_sfb, 253 pChVars[leftCh]->mask); 254 MODIFYING(pInputStream, mask) 255 RETURNING(hasmask) 256 257 IF (hasmask == MASK_ERROR) 258 THEN 259 status = 1; 260 ENDIF 261 pChVars[leftCh]->hasmask = hasmask; 262 pChVars[rightCh]->hasmask = hasmask; 263 264 ENDIF 265 266 ELSE 267 268 pChVars[leftCh]->hasmask = 0; 269 pChVars[rightCh]->hasmask = 0; 270 ENDIF(common_window) 271 272 ENDIF(id_syn_ele) 273 274 ENDIF (status) 275 276 ch = leftCh; 277 278 WHILE((ch <= rightCh) AND (status == SUCCESS)) 279 280 status = CALL getics( 281 pInputStream, 282 common_window, 283 pVars, 284 pChVars[ch], 285 pChVars[ch]->group, 286 &pChVars[ch]->max_sfb, 287 pChVars[ch]->cb_map, 288 &pChVars[ch]->tns, 289 pVars->winmap, 290 &pVars->pulseInfo, 291 pChVars[ch]->sect); 292 MODIFYING(pInputStream,pVarsp,ChVars[ch],group, 293 max_sfb,tns,pulseInfo,sect) 294 RETURNING(status) 295 296 ch++; 297 298 ENDWHILE 299 300 RETURN status; 301 302 ------------------------------------------------------------------------------ 303 RESOURCES USED 304 When the code is written for a specific target processor the 305 the resources used should be documented below. 306 307 STACK USAGE: [stack count for this module] + [variable to represent 308 stack usage for each subroutine called] 309 310 where: [stack usage variable] = stack usage for [subroutine 311 name] (see [filename].ext) 312 313 DATA MEMORY USED: x words 314 315 PROGRAM MEMORY USED: x words 316 317 CLOCK CYCLES: [cycle count equation for this module] + [variable 318 used to represent cycle count for each subroutine 319 called] 320 321 where: [cycle count variable] = cycle count for [subroutine 322 name] (see [filename].ext) 323 324 ------------------------------------------------------------------------------ 325 */ 326 327 328 /*---------------------------------------------------------------------------- 329 ; INCLUDES 330 ----------------------------------------------------------------------------*/ 331 #include "pv_audio_type_defs.h" 332 #include "aac_mem_funcs.h" 333 #include "huffman.h" 334 #include "e_maskstatus.h" 335 #include "e_elementid.h" 336 #include "get_ics_info.h" 337 338 /*---------------------------------------------------------------------------- 339 ; MACROS 340 ; Define module specific macros here 341 ----------------------------------------------------------------------------*/ 342 343 /*---------------------------------------------------------------------------- 344 ; DEFINES 345 ; Include all pre-processor statements here. Include conditional 346 ; compile variables also. 347 ----------------------------------------------------------------------------*/ 348 #define LEFT (0) 349 #define RIGHT (1) 350 /*---------------------------------------------------------------------------- 351 ; LOCAL FUNCTION DEFINITIONS 352 ; Function Prototype declaration 353 ----------------------------------------------------------------------------*/ 354 355 /*---------------------------------------------------------------------------- 356 ; LOCAL STORE/BUFFER/POINTER DEFINITIONS 357 ; Variable declaration - defined here and used outside this module 358 ----------------------------------------------------------------------------*/ 359 360 /*---------------------------------------------------------------------------- 361 ; EXTERNAL FUNCTION REFERENCES 362 ; Declare functions defined elsewhere and referenced in this module 363 ----------------------------------------------------------------------------*/ 364 365 /*---------------------------------------------------------------------------- 366 ; EXTERNAL GLOBAL STORE/BUFFER/POINTER REFERENCES 367 ; Declare variables used in this module but defined elsewhere 368 ----------------------------------------------------------------------------*/ 369 370 /*---------------------------------------------------------------------------- 371 ; FUNCTION CODE 372 ----------------------------------------------------------------------------*/ 373 Int huffdecode( 374 Int id_syn_ele, 375 BITS *pInputStream, 376 tDec_Int_File *pVars, 377 tDec_Int_Chan *pChVars[]) 378 379 { 380 /*---------------------------------------------------------------------------- 381 ; Define all local variables 382 ----------------------------------------------------------------------------*/ 383 Int ch; 384 Int common_window; 385 Int hasmask; 386 Int status = SUCCESS; 387 Int num_channels = 0; 388 MC_Info *pMcInfo; 389 390 per_chan_share_w_fxpCoef *pChLeftShare; /* Helper pointer */ 391 per_chan_share_w_fxpCoef *pChRightShare; /* Helper pointer */ 392 /*---------------------------------------------------------------------------- 393 ; Function body here 394 ----------------------------------------------------------------------------*/ 395 396 get9_n_lessbits( 397 LEN_TAG, 398 pInputStream); 399 400 /* suppose an un-supported id_syn_ele will never be passed */ 401 402 common_window = 0; 403 404 if (id_syn_ele == ID_CPE) 405 { 406 common_window = 407 get1bits(pInputStream); 408 } 409 410 pMcInfo = &pVars->mc_info; 411 412 /* 413 * check if provided info (num of channels) on audio config, 414 * matches read bitstream data, if not, allow update only once. 415 * In almost all cases it should match. 416 */ 417 if ((pMcInfo->ch_info[0].cpe != id_syn_ele)) 418 { 419 if (pVars->mc_info.implicit_channeling) /* check done only once */ 420 { 421 pMcInfo->ch_info[0].cpe = id_syn_ele & 1; /* collect info from bitstream 422 * implicit_channeling flag is locked 423 * after 1st frame, to avoid toggling 424 * parameter in the middle of the clip 425 */ 426 pMcInfo->nch = (id_syn_ele & 1) + 1; /* update number of channels */ 427 } 428 else 429 { 430 status = 1; /* ERROR break if syntax error persist */ 431 } 432 } 433 434 if (status == SUCCESS) 435 { 436 if (id_syn_ele == ID_SCE) 437 { 438 439 num_channels = 1; 440 pVars->hasmask = 0; 441 } 442 else if (id_syn_ele == ID_CPE) 443 { 444 pChLeftShare = pChVars[LEFT]->pShareWfxpCoef; 445 pChRightShare = pChVars[RIGHT]->pShareWfxpCoef; 446 num_channels = 2; 447 448 if (common_window != FALSE) 449 { 450 451 status = get_ics_info( 452 (tMP4AudioObjectType) pVars->mc_info.audioObjectType, 453 pInputStream, 454 (Bool)common_window, 455 (WINDOW_SEQUENCE *) & pChVars[LEFT]->wnd, 456 (WINDOW_SHAPE *) & pChVars[LEFT]->wnd_shape_this_bk, 457 pChLeftShare->group, 458 (Int *) & pChLeftShare->max_sfb, 459 pVars->winmap, 460 (LT_PRED_STATUS *) & pChLeftShare->lt_status, 461 (LT_PRED_STATUS *) & pChRightShare->lt_status); 462 463 if (status == SUCCESS) 464 { 465 /* copy left channel info to right channel */ 466 pChVars[RIGHT]->wnd = pChVars[LEFT]->wnd; 467 pChVars[RIGHT]->wnd_shape_this_bk = 468 pChVars[LEFT]->wnd_shape_this_bk; 469 pChRightShare->max_sfb = pChLeftShare->max_sfb; 470 pv_memcpy( 471 pChRightShare->group, 472 pChLeftShare->group, 473 NSHORT*sizeof(pChLeftShare->group[0])); 474 475 hasmask = getmask( 476 pVars->winmap[pChVars[LEFT]->wnd], 477 pInputStream, 478 pChLeftShare->group, 479 pChLeftShare->max_sfb, 480 pVars->mask); 481 482 if (hasmask == MASK_ERROR) 483 { 484 status = 1; /* ERROR code */ 485 } 486 pVars->hasmask = hasmask; 487 488 } /* if (status == 0) */ 489 } 490 else 491 { 492 pVars->hasmask = 0; 493 } /* if (common_window) */ 494 495 } /* if (id_syn_ele) */ 496 497 } /* if (status) */ 498 499 ch = 0; 500 while ((ch < num_channels) && (status == SUCCESS)) 501 { 502 pChLeftShare = pChVars[ch]->pShareWfxpCoef; 503 504 status = getics( 505 pInputStream, 506 common_window, 507 pVars, 508 pChVars[ch], 509 pChLeftShare->group, 510 &pChLeftShare->max_sfb, 511 pChLeftShare->cb_map, 512 &pChLeftShare->tns, 513 pVars->winmap, 514 &pVars->share.a.pulseInfo, 515 pVars->share.a.sect); 516 517 ch++; 518 519 } /* while (ch) */ 520 521 /*---------------------------------------------------------------------------- 522 ; Return status 523 ----------------------------------------------------------------------------*/ 524 525 return status; 526 527 } /* huffdecode */ 528 529
