quicktime/ffmpeg/libavcodec/golomb.h

   1 /*
   2  * exp golomb vlc stuff
   3  * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
   4  * Copyright (c) 2004 Alex Beregszaszi
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  *
  20  */
  21
  22 /**
  23  * @file golomb.h
  24  * @brief
  25  *     exp golomb vlc stuff
  26  * @author Michael Niedermayer <michaelni@gmx.at> and Alex Beregszaszi
  27  */
  28
  29 #define INVALID_VLC           0x80000000
  30
  31 extern const uint8_t ff_golomb_vlc_len[512];
  32 extern const uint8_t ff_ue_golomb_vlc_code[512];
  33 extern const  int8_t ff_se_golomb_vlc_code[512];
  34 extern const uint8_t ff_ue_golomb_len[256];
  35
  36 extern const uint8_t ff_interleaved_golomb_vlc_len[256];
  37 extern const uint8_t ff_interleaved_ue_golomb_vlc_code[256];
  38 extern const  int8_t ff_interleaved_se_golomb_vlc_code[256];
  39
  40
  41  /**
  42  * read unsigned exp golomb code.
  43  */
  44 static inline int get_ue_golomb(GetBitContext *gb){
  45     unsigned int buf;
  46     int log;
  47
  48     OPEN_READER(re, gb);
  49     UPDATE_CACHE(re, gb);
  50     buf=GET_CACHE(re, gb);
  51
  52     if(buf >= (1<<27)){
  53         buf >>= 32 - 9;
  54         LAST_SKIP_BITS(re, gb, ff_golomb_vlc_len[buf]);
  55         CLOSE_READER(re, gb);
  56
  57         return ff_ue_golomb_vlc_code[buf];
  58     }else{
  59         log= 2*av_log2(buf) - 31;
  60         buf>>= log;
  61         buf--;
  62         LAST_SKIP_BITS(re, gb, 32 - log);
  63         CLOSE_READER(re, gb);
  64
  65         return buf;
  66     }
  67 }
  68
  69 static inline int svq3_get_ue_golomb(GetBitContext *gb){
  70     uint32_t buf;
  71     int log;
  72
  73     OPEN_READER(re, gb);
  74     UPDATE_CACHE(re, gb);
  75     buf=GET_CACHE(re, gb);
  76
  77     if(buf&0xAA800000){
  78         buf >>= 32 - 8;
  79         LAST_SKIP_BITS(re, gb, ff_interleaved_golomb_vlc_len[buf]);
  80         CLOSE_READER(re, gb);
  81
  82         return ff_interleaved_ue_golomb_vlc_code[buf];
  83     }else{
  84         LAST_SKIP_BITS(re, gb, 8);
  85         UPDATE_CACHE(re, gb);
  86         buf |= 1 | (GET_CACHE(re, gb) >> 8);
  87
  88         if((buf & 0xAAAAAAAA) == 0)
  89             return INVALID_VLC;
  90
  91         for(log=31; (buf & 0x80000000) == 0; log--){
  92             buf = (buf << 2) - ((buf << log) >> (log - 1)) + (buf >> 30);
  93         }
  94
  95         LAST_SKIP_BITS(re, gb, 63 - 2*log - 8);
  96         CLOSE_READER(re, gb);
  97
  98         return ((buf << log) >> log) - 1;
  99     }
 100 }
 101
 102 /**
 103  * read unsigned truncated exp golomb code.
 104  */
 105 static inline int get_te0_golomb(GetBitContext *gb, int range){
 106     assert(range >= 1);
 107
 108     if(range==1)      return 0;
 109     else if(range==2) return get_bits1(gb)^1;
 110     else              return get_ue_golomb(gb);
 111 }
 112
 113 /**
 114  * read unsigned truncated exp golomb code.
 115  */
 116 static inline int get_te_golomb(GetBitContext *gb, int range){
 117     assert(range >= 1);
 118
 119     if(range==2) return get_bits1(gb)^1;
 120     else         return get_ue_golomb(gb);
 121 }
 122
 123
 124 /**
 125  * read signed exp golomb code.
 126  */
 127 static inline int get_se_golomb(GetBitContext *gb){
 128     unsigned int buf;
 129     int log;
 130
 131     OPEN_READER(re, gb);
 132     UPDATE_CACHE(re, gb);
 133     buf=GET_CACHE(re, gb);
 134
 135     if(buf >= (1<<27)){
 136         buf >>= 32 - 9;
 137         LAST_SKIP_BITS(re, gb, ff_golomb_vlc_len[buf]);
 138         CLOSE_READER(re, gb);
 139
 140         return ff_se_golomb_vlc_code[buf];
 141     }else{
 142         log= 2*av_log2(buf) - 31;
 143         buf>>= log;
 144
 145         LAST_SKIP_BITS(re, gb, 32 - log);
 146         CLOSE_READER(re, gb);
 147
 148         if(buf&1) buf= -(buf>>1);
 149         else      buf=  (buf>>1);
 150
 151         return buf;
 152     }
 153 }
 154
 155 static inline int svq3_get_se_golomb(GetBitContext *gb){
 156     unsigned int buf;
 157     int log;
 158
 159     OPEN_READER(re, gb);
 160     UPDATE_CACHE(re, gb);
 161     buf=GET_CACHE(re, gb);
 162
 163     if(buf&0xAA800000){
 164         buf >>= 32 - 8;
 165         LAST_SKIP_BITS(re, gb, ff_interleaved_golomb_vlc_len[buf]);
 166         CLOSE_READER(re, gb);
 167
 168         return ff_interleaved_se_golomb_vlc_code[buf];
 169     }else{
 170         LAST_SKIP_BITS(re, gb, 8);
 171         UPDATE_CACHE(re, gb);
 172         buf |= 1 | (GET_CACHE(re, gb) >> 8);
 173
 174         if((buf & 0xAAAAAAAA) == 0)
 175             return INVALID_VLC;
 176
 177         for(log=31; (buf & 0x80000000) == 0; log--){
 178             buf = (buf << 2) - ((buf << log) >> (log - 1)) + (buf >> 30);
 179         }
 180
 181         LAST_SKIP_BITS(re, gb, 63 - 2*log - 8);
 182         CLOSE_READER(re, gb);
 183
 184         return (signed) (((((buf << log) >> log) - 1) ^ -(buf & 0x1)) + 1) >> 1;
 185     }
 186 }
 187
 188 /**
 189  * read unsigned golomb rice code (ffv1).
 190  */
 191 static inline int get_ur_golomb(GetBitContext *gb, int k, int limit, int esc_len){
 192     unsigned int buf;
 193     int log;
 194
 195     OPEN_READER(re, gb);
 196     UPDATE_CACHE(re, gb);
 197     buf=GET_CACHE(re, gb);
 198
 199     log= av_log2(buf);
 200
 201     if(log > 31-limit){
 202         buf >>= log - k;
 203         buf += (30-log)<<k;
 204         LAST_SKIP_BITS(re, gb, 32 + k - log);
 205         CLOSE_READER(re, gb);
 206
 207         return buf;
 208     }else{
 209         buf >>= 32 - limit - esc_len;
 210         LAST_SKIP_BITS(re, gb, esc_len + limit);
 211         CLOSE_READER(re, gb);
 212
 213         return buf + limit - 1;
 214     }
 215 }
 216
 217 /**
 218  * read unsigned golomb rice code (jpegls).
 219  */
 220 static inline int get_ur_golomb_jpegls(GetBitContext *gb, int k, int limit, int esc_len){
 221     unsigned int buf;
 222     int log;
 223
 224     OPEN_READER(re, gb);
 225     UPDATE_CACHE(re, gb);
 226     buf=GET_CACHE(re, gb);
 227
 228     log= av_log2(buf);
 229
 230     if(log > 31-11){
 231         buf >>= log - k;
 232         buf += (30-log)<<k;
 233         LAST_SKIP_BITS(re, gb, 32 + k - log);
 234         CLOSE_READER(re, gb);
 235
 236         return buf;
 237     }else{
 238         int i;
 239         for(i=0; SHOW_UBITS(re, gb, 1) == 0; i++){
 240             LAST_SKIP_BITS(re, gb, 1);
 241             UPDATE_CACHE(re, gb);
 242         }
 243         SKIP_BITS(re, gb, 1);
 244
 245         if(i < limit - 1){
 246             if(k){
 247                 buf = SHOW_UBITS(re, gb, k);
 248                 LAST_SKIP_BITS(re, gb, k);
 249             }else{
 250                 buf=0;
 251             }
 252
 253             CLOSE_READER(re, gb);
 254             return buf + (i<<k);
 255         }else if(i == limit - 1){
 256             buf = SHOW_UBITS(re, gb, esc_len);
 257             LAST_SKIP_BITS(re, gb, esc_len);
 258             CLOSE_READER(re, gb);
 259
 260             return buf + 1;
 261         }else
 262             return -1;
 263     }
 264 }
 265
 266 /**
 267  * read signed golomb rice code (ffv1).
 268  */
 269 static inline int get_sr_golomb(GetBitContext *gb, int k, int limit, int esc_len){
 270     int v= get_ur_golomb(gb, k, limit, esc_len);
 271
 272     v++;
 273     if (v&1) return v>>1;
 274     else return -(v>>1);
 275
 276 //    return (v>>1) ^ -(v&1);
 277 }
 278
 279 /**
 280  * read signed golomb rice code (flac).
 281  */
 282 static inline int get_sr_golomb_flac(GetBitContext *gb, int k, int limit, int esc_len){
 283     int v= get_ur_golomb_jpegls(gb, k, limit, esc_len);
 284     return (v>>1) ^ -(v&1);
 285 }
 286
 287 /**
 288  * read unsigned golomb rice code (shorten).
 289  */
 290 static inline unsigned int get_ur_golomb_shorten(GetBitContext *gb, int k){
 291         return get_ur_golomb_jpegls(gb, k, INT_MAX, 0);
 292 }
 293
 294 /**
 295  * read signed golomb rice code (shorten).
 296  */
 297 static inline int get_sr_golomb_shorten(GetBitContext* gb, int k)
 298 {
 299     int uvar = get_ur_golomb_jpegls(gb, k + 1, INT_MAX, 0);
 300     if (uvar & 1)
 301         return ~(uvar >> 1);
 302     else
 303         return uvar >> 1;
 304 }
 305
 306
 307
 308 #ifdef TRACE
 309
 310 static inline int get_ue(GetBitContext *s, char *file, const char *func, int line){
 311     int show= show_bits(s, 24);
 312     int pos= get_bits_count(s);
 313     int i= get_ue_golomb(s);
 314     int len= get_bits_count(s) - pos;
 315     int bits= show>>(24-len);
 316
 317     print_bin(bits, len);
 318
 319     av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d ue  @%5d in %s %s:%d\n", bits, len, i, pos, file, func, line);
 320
 321     return i;
 322 }
 323
 324 static inline int get_se(GetBitContext *s, char *file, const char *func, int line){
 325     int show= show_bits(s, 24);
 326     int pos= get_bits_count(s);
 327     int i= get_se_golomb(s);
 328     int len= get_bits_count(s) - pos;
 329     int bits= show>>(24-len);
 330
 331     print_bin(bits, len);
 332
 333     av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d se  @%5d in %s %s:%d\n", bits, len, i, pos, file, func, line);
 334
 335     return i;
 336 }
 337
 338 static inline int get_te(GetBitContext *s, int r, char *file, const char *func, int line){
 339     int show= show_bits(s, 24);
 340     int pos= get_bits_count(s);
 341     int i= get_te0_golomb(s, r);
 342     int len= get_bits_count(s) - pos;
 343     int bits= show>>(24-len);
 344
 345     print_bin(bits, len);
 346
 347     av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d te  @%5d in %s %s:%d\n", bits, len, i, pos, file, func, line);
 348
 349     return i;
 350 }
 351
 352 #define get_ue_golomb(a) get_ue(a, __FILE__, __PRETTY_FUNCTION__, __LINE__)
 353 #define get_se_golomb(a) get_se(a, __FILE__, __PRETTY_FUNCTION__, __LINE__)
 354 #define get_te_golomb(a, r) get_te(a, r, __FILE__, __PRETTY_FUNCTION__, __LINE__)
 355 #define get_te0_golomb(a, r) get_te(a, r, __FILE__, __PRETTY_FUNCTION__, __LINE__)
 356
 357 #endif
 358
 359 /**
 360  * write unsigned exp golomb code.
 361  */
 362 static inline void set_ue_golomb(PutBitContext *pb, int i){
 363     int e;
 364
 365     assert(i>=0);
 366
 367 #if 0
 368     if(i=0){
 369         put_bits(pb, 1, 1);
 370         return;
 371     }
 372 #endif
 373     if(i<256)
 374         put_bits(pb, ff_ue_golomb_len[i], i+1);
 375     else{
 376         e= av_log2(i+1);
 377
 378         put_bits(pb, 2*e+1, i+1);
 379     }
 380 }
 381
 382 /**
 383  * write truncated unsigned exp golomb code.
 384  */
 385 static inline void set_te_golomb(PutBitContext *pb, int i, int range){
 386     assert(range >= 1);
 387     assert(i<=range);
 388
 389     if(range==2) put_bits(pb, 1, i^1);
 390     else         set_ue_golomb(pb, i);
 391 }
 392
 393 /**
 394  * write signed exp golomb code.
 395  */
 396 static inline void set_se_golomb(PutBitContext *pb, int i){
 397 #if 0
 398     if(i<=0) i= -2*i;
 399     else     i=  2*i-1;
 400 #elif 1
 401     i= 2*i-1;
 402     if(i<0) i^= -1; //FIXME check if gcc does the right thing
 403 #else
 404     i= 2*i-1;
 405     i^= (i>>31);
 406 #endif
 407     set_ue_golomb(pb, i);
 408 }
 409
 410 /**
 411  * write unsigned golomb rice code (ffv1).
 412  */
 413 static inline void set_ur_golomb(PutBitContext *pb, int i, int k, int limit, int esc_len){
 414     int e;
 415
 416     assert(i>=0);
 417
 418     e= i>>k;
 419     if(e<limit){
 420         put_bits(pb, e + k + 1, (1<<k) + (i&((1<<k)-1)));
 421     }else{
 422         put_bits(pb, limit + esc_len, i - limit + 1);
 423     }
 424 }
 425
 426 /**
 427  * write unsigned golomb rice code (jpegls).
 428  */
 429 static inline void set_ur_golomb_jpegls(PutBitContext *pb, int i, int k, int limit, int esc_len){
 430     int e;
 431
 432     assert(i>=0);
 433
 434     e= (i>>k) + 1;
 435     if(e<limit){
 436         put_bits(pb, e, 1);
 437         if(k)
 438             put_bits(pb, k, i&((1<<k)-1));
 439     }else{
 440         put_bits(pb, limit  , 1);
 441         put_bits(pb, esc_len, i - 1);
 442     }
 443 }
 444
 445 /**
 446  * write signed golomb rice code (ffv1).
 447  */
 448 static inline void set_sr_golomb(PutBitContext *pb, int i, int k, int limit, int esc_len){
 449     int v;
 450
 451     v = -2*i-1;
 452     v ^= (v>>31);
 453
 454     set_ur_golomb(pb, v, k, limit, esc_len);
 455 }
 456
 457 /**
 458  * write signed golomb rice code (flac).
 459  */
 460 static inline void set_sr_golomb_flac(PutBitContext *pb, int i, int k, int limit, int esc_len){
 461     int v;
 462
 463     v = -2*i-1;
 464     v ^= (v>>31);
 465
 466     set_ur_golomb_jpegls(pb, v, k, limit, esc_len);
 467 }