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: q_normalize.c 21 22 ------------------------------------------------------------------------------ 23 REVISION HISTORY 24 25 Description: 26 (1) Modify to include search over the scalefactor bands to insure 27 that the data is using all 31 data-bits. 28 29 Description: 30 (1) Modify to remove search over the scalefactor bands to insure 31 that the data is using all 31 data-bits. 32 (Pushed out into separate function) 33 (2) Change variable "k" to more descriptive "shift_amt" 34 (3) Update pseudocode to reflect removed code. 35 (4) Add PV Copyright notice. 36 37 Description: 38 (1) Modified to protect q-normalize from shifting by amounts >= 32. 39 40 Description: 41 (1) Delete local variable idx_count. 42 43 Description: 44 (1) Included search for max in each frame, modified interface. 45 46 Description: 47 (1) unrolled loop based on the fact that the size of each scale band 48 is always an even number. 49 50 Description:Check shift, if zero, do not shift. 51 52 Description: Eliminated warning: non use variable "i" and memset function 53 definition 54 55 Who: Date: 56 Description: 57 ------------------------------------------------------------------------------ 58 INPUT AND OUTPUT DEFINITIONS 59 60 Inputs: 61 qFormat[] = Array of qFormats, one per scalefactor band. [ Int ] 62 63 pFrameInfo = Pointer to structure that holds information about each group. 64 (long block flag, number of windows, scalefactor bands, etc.) 65 [const FrameInfo] 66 67 coef[] = Array of the spectral coefficients for one channel. [ Int32 ] 68 69 Local Stores/Buffers/Pointers Needed: 70 None 71 72 Global Stores/Buffers/Pointers Needed: 73 None 74 75 Outputs: 76 min_q = The common q-format for the entire frame. [Int] 77 78 Pointers and Buffers Modified: 79 coef[] = Array of spectral data, now normalized to one q-format. 80 81 Local Stores Modified: 82 None 83 84 Global Stores Modified: 85 None 86 87 ------------------------------------------------------------------------------ 88 FUNCTION DESCRIPTION 89 90 This module first scans every scalefactor band for the frame, insuring that 91 at least one element in that scalefactor band is using all available bits. 92 If not, the elements in the scalefactor band are shifted up to use all 31 93 data bits. The q-format is adjusted accordingly. 94 95 This module then scans the q-formats for each scalefactor band. 96 Upon finding the minimum q-format in the frame, the coefficients in each 97 scalefactor band are normalized to the minimum q-format. 98 The minimum q-format is then returned to the calling function, which is now 99 the q-format for the entire frame. 100 101 ------------------------------------------------------------------------------ 102 REQUIREMENTS 103 104 ------------------------------------------------------------------------------ 105 REFERENCES 106 107 ------------------------------------------------------------------------------ 108 PSEUDO-CODE 109 110 nwin = pFrameInfo->num_win; 111 112 pQformat = &(qFormat[0]); 113 pSfbPerWin = &(pFrameInfo->sfb_per_win[0]); 114 pCoef = &(coef[0]); 115 116 FOR (win = nwin; win > 0; win--) 117 118 nsfb = *(pSfbPerWin++); 119 120 FOR (sfb = nsfb; sfb > 0; sfb--) 121 122 IF ( *(pQformat) < min_q) 123 min_q = *(pQformat); 124 ENDIF 125 126 pQformat++; 127 128 ENDFOR 129 130 ENDFOR 131 132 pQformat = &(qFormat[0]); 133 pSfbPerWin = &(pFrameInfo->sfb_per_win[0]); 134 pCoef = &(coef[0]); 135 136 FOR (win = 0; win < nwin; win++) 137 138 stop_idx = 0; 139 140 nsfb = *(pSfbPerWin++); 141 142 pWinSfbTop = &(pFrameInfo->win_sfb_top[win][0]); 143 144 FOR (sfb = nsfb; sfb > 0; sfb--) 145 146 sfbWidth = *(pWinSfbTop++) - stop_idx; 147 148 stop_idx += sfbWidth; 149 150 k = *(pQformat++) - min_q; 151 152 IF (k < 32) 153 THEN 154 FOR (; sfbWidth > 0; sfbWidth--) 155 *(pCoef++) >>= k; 156 ENDFOR 157 ELSE 158 FOR (; sfbWidth > 0; sfbWidth--) 159 *(pCoef++) = 0; 160 ENDFOR 161 ENDIF 162 163 ENDFOR 164 165 ENDFOR 166 167 return min_q; 168 169 ------------------------------------------------------------------------------ 170 RESOURCES USED 171 When the code is written for a specific target processor the 172 the resources used should be documented below. 173 174 STACK USAGE: [stack count for this module] + [variable to represent 175 stack usage for each subroutine called] 176 177 where: [stack usage variable] = stack usage for [subroutine 178 name] (see [filename].ext) 179 180 DATA MEMORY USED: x words 181 182 PROGRAM MEMORY USED: x words 183 184 CLOCK CYCLES: [cycle count equation for this module] + [variable 185 used to represent cycle count for each subroutine 186 called] 187 188 where: [cycle count variable] = cycle count for [subroutine 189 name] (see [filename].ext) 190 191 ------------------------------------------------------------------------------ 192 */ 193 194 195 /*---------------------------------------------------------------------------- 196 ; INCLUDES 197 ----------------------------------------------------------------------------*/ 198 #include "pv_audio_type_defs.h" 199 #include "s_frameinfo.h" 200 #include "q_normalize.h" 201 #include "aac_mem_funcs.h" /* For pv_memset */ 202 203 /*---------------------------------------------------------------------------- 204 ; MACROS 205 ; Define module specific macros here 206 ----------------------------------------------------------------------------*/ 207 208 /*---------------------------------------------------------------------------- 209 ; DEFINES 210 ; Include all pre-processor statements here. Include conditional 211 ; compile variables also. 212 ----------------------------------------------------------------------------*/ 213 214 /*---------------------------------------------------------------------------- 215 ; LOCAL FUNCTION DEFINITIONS 216 ; Function Prototype declaration 217 ----------------------------------------------------------------------------*/ 218 219 /*---------------------------------------------------------------------------- 220 ; LOCAL STORE/BUFFER/POINTER DEFINITIONS 221 ; Variable declaration - defined here and used outside this module 222 ----------------------------------------------------------------------------*/ 223 224 /*---------------------------------------------------------------------------- 225 ; EXTERNAL FUNCTION REFERENCES 226 ; Declare functions defined elsewhere and referenced in this module 227 ----------------------------------------------------------------------------*/ 228 229 /*---------------------------------------------------------------------------- 230 ; EXTERNAL GLOBAL STORE/BUFFER/POINTER REFERENCES 231 ; Declare variables used in this module but defined elsewhere 232 ----------------------------------------------------------------------------*/ 233 234 /*---------------------------------------------------------------------------- 235 ; FUNCTION CODE 236 ----------------------------------------------------------------------------*/ 237 Int q_normalize( 238 Int qFormat[], 239 const FrameInfo *pFrameInfo, 240 Int32 abs_max_per_window[], 241 Int32 coef[]) 242 { 243 Int sfb; 244 Int nsfb; 245 Int win; 246 Int nwin; 247 Int sfbWidth; 248 249 Int shift_amt; 250 251 /* Initialize min_q to a very large value */ 252 Int min_q = 1000; 253 254 Int stop_idx = 0; 255 256 const Int *pSfbPerWin; 257 const Int16 *pWinSfbTop; 258 259 Int *pQformat; 260 Int32 *pCoef; 261 262 nwin = pFrameInfo->num_win; 263 264 /* Find the minimum q format */ 265 pQformat = &(qFormat[0]); 266 pSfbPerWin = &(pFrameInfo->sfb_per_win[0]); 267 268 for (win = nwin; win != 0; win--) 269 { 270 271 nsfb = *(pSfbPerWin++); 272 273 if (nsfb < 0 || nsfb > MAXBANDS) 274 { 275 break; /* avoid any processing on error condition */ 276 } 277 278 for (sfb = nsfb; sfb != 0; sfb--) 279 { 280 Int qformat = *(pQformat++); 281 if (qformat < min_q) 282 { 283 min_q = qformat; 284 } 285 } 286 287 } /* for(win) */ 288 289 /* Normalize the coefs in each scalefactor band to one q-format */ 290 pQformat = &(qFormat[0]); 291 pSfbPerWin = &(pFrameInfo->sfb_per_win[0]); 292 pCoef = &(coef[0]); 293 294 for (win = 0; win < nwin; win++) 295 { 296 297 Int32 max = 0; 298 stop_idx = 0; 299 300 nsfb = *(pSfbPerWin++); 301 302 if (nsfb < 0 || nsfb > MAXBANDS) 303 { 304 break; /* avoid any processing on error condition */ 305 } 306 307 pWinSfbTop = &(pFrameInfo->win_sfb_top[win][0]); 308 309 for (sfb = nsfb; sfb != 0; sfb--) 310 { 311 Int tmp1, tmp2; 312 tmp1 = *(pWinSfbTop++); 313 tmp2 = *(pQformat++); 314 sfbWidth = tmp1 - stop_idx; 315 316 if (sfbWidth < 2) 317 { 318 break; /* will lead to error condition */ 319 } 320 321 stop_idx += sfbWidth; 322 323 shift_amt = tmp2 - min_q; 324 325 if (shift_amt == 0) 326 { 327 Int32 tmp1, tmp2; 328 tmp1 = *(pCoef++); 329 tmp2 = *(pCoef++); 330 /* 331 * sfbWidth is always an even number 332 * (check tables in pg.66 IS0 14496-3) 333 */ 334 for (Int i = (sfbWidth >> 1) - 1; i != 0; i--) 335 { 336 max |= (tmp1 >> 31) ^ tmp1; 337 max |= (tmp2 >> 31) ^ tmp2; 338 tmp1 = *(pCoef++); 339 tmp2 = *(pCoef++); 340 } 341 max |= (tmp1 >> 31) ^ tmp1; 342 max |= (tmp2 >> 31) ^ tmp2; 343 344 } 345 else 346 { 347 if (shift_amt < 31) 348 { 349 Int32 tmp1, tmp2; 350 tmp1 = *(pCoef++) >> shift_amt; 351 tmp2 = *(pCoef--) >> shift_amt; 352 /* 353 * sfbWidth is always an even number 354 * (check tables in pg.66 IS0 14496-3) 355 */ 356 for (Int i = (sfbWidth >> 1) - 1; i != 0; i--) 357 { 358 *(pCoef++) = tmp1; 359 *(pCoef++) = tmp2; 360 361 max |= (tmp1 >> 31) ^ tmp1; 362 max |= (tmp2 >> 31) ^ tmp2; 363 tmp1 = *(pCoef++) >> shift_amt; 364 tmp2 = *(pCoef--) >> shift_amt; 365 366 } 367 *(pCoef++) = tmp1; 368 *(pCoef++) = tmp2; 369 max |= (tmp1 >> 31) ^ tmp1; 370 max |= (tmp2 >> 31) ^ tmp2; 371 372 } 373 else 374 { 375 pv_memset(pCoef, 0, sizeof(Int32)*sfbWidth); 376 pCoef += sfbWidth; 377 } 378 } 379 380 abs_max_per_window[win] = max; 381 382 } 383 384 } /* for (win) */ 385 386 return min_q; 387 388 } /* normalize() */ 389
