FFmpeg: libavcodec/golomb.h Source File

00001 /*
00002  * exp golomb vlc stuff
00003  * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
00004  * Copyright (c) 2004 Alex Beregszaszi
00005  *
00006  * This file is part of FFmpeg.
00007  *
00008  * FFmpeg is free software; you can redistribute it and/or
00009  * modify it under the terms of the GNU Lesser General Public
00010  * License as published by the Free Software Foundation; either
00011  * version 2.1 of the License, or (at your option) any later version.
00012  *
00013  * FFmpeg is distributed in the hope that it will be useful,
00014  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00015  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00016  * Lesser General Public License for more details.
00017  *
00018  * You should have received a copy of the GNU Lesser General Public
00019  * License along with FFmpeg; if not, write to the Free Software
00020  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00021  */
00022 
00030 #ifndef AVCODEC_GOLOMB_H
00031 #define AVCODEC_GOLOMB_H
00032 
00033 #include <stdint.h>
00034 #include "bitstream.h"
00035 
00036 #define INVALID_VLC           0x80000000
00037 
00038 extern const uint8_t ff_golomb_vlc_len[512];
00039 extern const uint8_t ff_ue_golomb_vlc_code[512];
00040 extern const  int8_t ff_se_golomb_vlc_code[512];
00041 extern const uint8_t ff_ue_golomb_len[256];
00042 
00043 extern const uint8_t ff_interleaved_golomb_vlc_len[256];
00044 extern const uint8_t ff_interleaved_ue_golomb_vlc_code[256];
00045 extern const  int8_t ff_interleaved_se_golomb_vlc_code[256];
00046 extern const uint8_t ff_interleaved_dirac_golomb_vlc_code[256];
00047 
00048 
00052 static inline int get_ue_golomb(GetBitContext *gb){
00053     unsigned int buf;
00054     int log;
00055 
00056     OPEN_READER(re, gb);
00057     UPDATE_CACHE(re, gb);
00058     buf=GET_CACHE(re, gb);
00059 
00060     if(buf >= (1<<27)){
00061         buf >>= 32 - 9;
00062         LAST_SKIP_BITS(re, gb, ff_golomb_vlc_len[buf]);
00063         CLOSE_READER(re, gb);
00064 
00065         return ff_ue_golomb_vlc_code[buf];
00066     }else{
00067         log= 2*av_log2(buf) - 31;
00068         buf>>= log;
00069         buf--;
00070         LAST_SKIP_BITS(re, gb, 32 - log);
00071         CLOSE_READER(re, gb);
00072 
00073         return buf;
00074     }
00075 }
00076 
00081 static inline int get_ue_golomb_31(GetBitContext *gb){
00082     unsigned int buf;
00083 
00084     OPEN_READER(re, gb);
00085     UPDATE_CACHE(re, gb);
00086     buf=GET_CACHE(re, gb);
00087 
00088     buf >>= 32 - 9;
00089     LAST_SKIP_BITS(re, gb, ff_golomb_vlc_len[buf]);
00090     CLOSE_READER(re, gb);
00091 
00092     return ff_ue_golomb_vlc_code[buf];
00093 }
00094 
00095 static inline int svq3_get_ue_golomb(GetBitContext *gb){
00096     uint32_t buf;
00097 
00098     OPEN_READER(re, gb);
00099     UPDATE_CACHE(re, gb);
00100     buf=GET_CACHE(re, gb);
00101 
00102     if(buf&0xAA800000){
00103         buf >>= 32 - 8;
00104         LAST_SKIP_BITS(re, gb, ff_interleaved_golomb_vlc_len[buf]);
00105         CLOSE_READER(re, gb);
00106 
00107         return ff_interleaved_ue_golomb_vlc_code[buf];
00108     }else{
00109         int ret = 1;
00110 
00111         while (1) {
00112             buf >>= 32 - 8;
00113             LAST_SKIP_BITS(re, gb, FFMIN(ff_interleaved_golomb_vlc_len[buf], 8));
00114 
00115             if (ff_interleaved_golomb_vlc_len[buf] != 9){
00116                 ret <<= (ff_interleaved_golomb_vlc_len[buf] - 1) >> 1;
00117                 ret |= ff_interleaved_dirac_golomb_vlc_code[buf];
00118                 break;
00119             }
00120             ret = (ret << 4) | ff_interleaved_dirac_golomb_vlc_code[buf];
00121             UPDATE_CACHE(re, gb);
00122             buf = GET_CACHE(re, gb);
00123         }
00124 
00125         CLOSE_READER(re, gb);
00126         return ret - 1;
00127     }
00128 }
00129 
00133 static inline int get_te0_golomb(GetBitContext *gb, int range){
00134     assert(range >= 1);
00135 
00136     if(range==1)      return 0;
00137     else if(range==2) return get_bits1(gb)^1;
00138     else              return get_ue_golomb(gb);
00139 }
00140 
00144 static inline int get_te_golomb(GetBitContext *gb, int range){
00145     assert(range >= 1);
00146 
00147     if(range==2) return get_bits1(gb)^1;
00148     else         return get_ue_golomb(gb);
00149 }
00150 
00151 
00155 static inline int get_se_golomb(GetBitContext *gb){
00156     unsigned int buf;
00157     int log;
00158 
00159     OPEN_READER(re, gb);
00160     UPDATE_CACHE(re, gb);
00161     buf=GET_CACHE(re, gb);
00162 
00163     if(buf >= (1<<27)){
00164         buf >>= 32 - 9;
00165         LAST_SKIP_BITS(re, gb, ff_golomb_vlc_len[buf]);
00166         CLOSE_READER(re, gb);
00167 
00168         return ff_se_golomb_vlc_code[buf];
00169     }else{
00170         log= 2*av_log2(buf) - 31;
00171         buf>>= log;
00172 
00173         LAST_SKIP_BITS(re, gb, 32 - log);
00174         CLOSE_READER(re, gb);
00175 
00176         if(buf&1) buf= -(buf>>1);
00177         else      buf=  (buf>>1);
00178 
00179         return buf;
00180     }
00181 }
00182 
00183 static inline int svq3_get_se_golomb(GetBitContext *gb){
00184     unsigned int buf;
00185     int log;
00186 
00187     OPEN_READER(re, gb);
00188     UPDATE_CACHE(re, gb);
00189     buf=GET_CACHE(re, gb);
00190 
00191     if(buf&0xAA800000){
00192         buf >>= 32 - 8;
00193         LAST_SKIP_BITS(re, gb, ff_interleaved_golomb_vlc_len[buf]);
00194         CLOSE_READER(re, gb);
00195 
00196         return ff_interleaved_se_golomb_vlc_code[buf];
00197     }else{
00198         LAST_SKIP_BITS(re, gb, 8);
00199         UPDATE_CACHE(re, gb);
00200         buf |= 1 | (GET_CACHE(re, gb) >> 8);
00201 
00202         if((buf & 0xAAAAAAAA) == 0)
00203             return INVALID_VLC;
00204 
00205         for(log=31; (buf & 0x80000000) == 0; log--){
00206             buf = (buf << 2) - ((buf << log) >> (log - 1)) + (buf >> 30);
00207         }
00208 
00209         LAST_SKIP_BITS(re, gb, 63 - 2*log - 8);
00210         CLOSE_READER(re, gb);
00211 
00212         return (signed) (((((buf << log) >> log) - 1) ^ -(buf & 0x1)) + 1) >> 1;
00213     }
00214 }
00215 
00216 static inline int dirac_get_se_golomb(GetBitContext *gb){
00217     uint32_t buf;
00218     uint32_t ret;
00219 
00220     ret = svq3_get_ue_golomb(gb);
00221 
00222     if (ret) {
00223         OPEN_READER(re, gb);
00224         UPDATE_CACHE(re, gb);
00225         buf = SHOW_SBITS(re, gb, 1);
00226         LAST_SKIP_BITS(re, gb, 1);
00227         ret = (ret ^ buf) - buf;
00228         CLOSE_READER(re, gb);
00229     }
00230 
00231     return ret;
00232 }
00233 
00237 static inline int get_ur_golomb(GetBitContext *gb, int k, int limit, int esc_len){
00238     unsigned int buf;
00239     int log;
00240 
00241     OPEN_READER(re, gb);
00242     UPDATE_CACHE(re, gb);
00243     buf=GET_CACHE(re, gb);
00244 
00245     log= av_log2(buf);
00246 
00247     if(log > 31-limit){
00248         buf >>= log - k;
00249         buf += (30-log)<<k;
00250         LAST_SKIP_BITS(re, gb, 32 + k - log);
00251         CLOSE_READER(re, gb);
00252 
00253         return buf;
00254     }else{
00255         buf >>= 32 - limit - esc_len;
00256         LAST_SKIP_BITS(re, gb, esc_len + limit);
00257         CLOSE_READER(re, gb);
00258 
00259         return buf + limit - 1;
00260     }
00261 }
00262 
00266 static inline int get_ur_golomb_jpegls(GetBitContext *gb, int k, int limit, int esc_len){
00267     unsigned int buf;
00268     int log;
00269 
00270     OPEN_READER(re, gb);
00271     UPDATE_CACHE(re, gb);
00272     buf=GET_CACHE(re, gb);
00273 
00274     log= av_log2(buf);
00275 
00276     if(log - k >= 32-MIN_CACHE_BITS+(MIN_CACHE_BITS==32) && 32-log < limit){
00277         buf >>= log - k;
00278         buf += (30-log)<<k;
00279         LAST_SKIP_BITS(re, gb, 32 + k - log);
00280         CLOSE_READER(re, gb);
00281 
00282         return buf;
00283     }else{
00284         int i;
00285         for(i=0; SHOW_UBITS(re, gb, 1) == 0; i++){
00286             LAST_SKIP_BITS(re, gb, 1);
00287             UPDATE_CACHE(re, gb);
00288         }
00289         SKIP_BITS(re, gb, 1);
00290 
00291         if(i < limit - 1){
00292             if(k){
00293                 buf = SHOW_UBITS(re, gb, k);
00294                 LAST_SKIP_BITS(re, gb, k);
00295             }else{
00296                 buf=0;
00297             }
00298 
00299             CLOSE_READER(re, gb);
00300             return buf + (i<<k);
00301         }else if(i == limit - 1){
00302             buf = SHOW_UBITS(re, gb, esc_len);
00303             LAST_SKIP_BITS(re, gb, esc_len);
00304             CLOSE_READER(re, gb);
00305 
00306             return buf + 1;
00307         }else
00308             return -1;
00309     }
00310 }
00311 
00315 static inline int get_sr_golomb(GetBitContext *gb, int k, int limit, int esc_len){
00316     int v= get_ur_golomb(gb, k, limit, esc_len);
00317 
00318     v++;
00319     if (v&1) return v>>1;
00320     else return -(v>>1);
00321 
00322 //    return (v>>1) ^ -(v&1);
00323 }
00324 
00328 static inline int get_sr_golomb_flac(GetBitContext *gb, int k, int limit, int esc_len){
00329     int v= get_ur_golomb_jpegls(gb, k, limit, esc_len);
00330     return (v>>1) ^ -(v&1);
00331 }
00332 
00336 static inline unsigned int get_ur_golomb_shorten(GetBitContext *gb, int k){
00337         return get_ur_golomb_jpegls(gb, k, INT_MAX, 0);
00338 }
00339 
00343 static inline int get_sr_golomb_shorten(GetBitContext* gb, int k)
00344 {
00345     int uvar = get_ur_golomb_jpegls(gb, k + 1, INT_MAX, 0);
00346     if (uvar & 1)
00347         return ~(uvar >> 1);
00348     else
00349         return uvar >> 1;
00350 }
00351 
00352 
00353 
00354 #ifdef TRACE
00355 
00356 static inline int get_ue(GetBitContext *s, char *file, const char *func, int line){
00357     int show= show_bits(s, 24);
00358     int pos= get_bits_count(s);
00359     int i= get_ue_golomb(s);
00360     int len= get_bits_count(s) - pos;
00361     int bits= show>>(24-len);
00362 
00363     print_bin(bits, len);
00364 
00365     av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d ue  @%5d in %s %s:%d\n", bits, len, i, pos, file, func, line);
00366 
00367     return i;
00368 }
00369 
00370 static inline int get_se(GetBitContext *s, char *file, const char *func, int line){
00371     int show= show_bits(s, 24);
00372     int pos= get_bits_count(s);
00373     int i= get_se_golomb(s);
00374     int len= get_bits_count(s) - pos;
00375     int bits= show>>(24-len);
00376 
00377     print_bin(bits, len);
00378 
00379     av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d se  @%5d in %s %s:%d\n", bits, len, i, pos, file, func, line);
00380 
00381     return i;
00382 }
00383 
00384 static inline int get_te(GetBitContext *s, int r, char *file, const char *func, int line){
00385     int show= show_bits(s, 24);
00386     int pos= get_bits_count(s);
00387     int i= get_te0_golomb(s, r);
00388     int len= get_bits_count(s) - pos;
00389     int bits= show>>(24-len);
00390 
00391     print_bin(bits, len);
00392 
00393     av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d te  @%5d in %s %s:%d\n", bits, len, i, pos, file, func, line);
00394 
00395     return i;
00396 }
00397 
00398 #define get_ue_golomb(a) get_ue(a, __FILE__, __PRETTY_FUNCTION__, __LINE__)
00399 #define get_se_golomb(a) get_se(a, __FILE__, __PRETTY_FUNCTION__, __LINE__)
00400 #define get_te_golomb(a, r) get_te(a, r, __FILE__, __PRETTY_FUNCTION__, __LINE__)
00401 #define get_te0_golomb(a, r) get_te(a, r, __FILE__, __PRETTY_FUNCTION__, __LINE__)
00402 
00403 #endif
00404 
00408 static inline void set_ue_golomb(PutBitContext *pb, int i){
00409     int e;
00410 
00411     assert(i>=0);
00412 
00413 #if 0
00414     if(i=0){
00415         put_bits(pb, 1, 1);
00416         return;
00417     }
00418 #endif
00419     if(i<256)
00420         put_bits(pb, ff_ue_golomb_len[i], i+1);
00421     else{
00422         e= av_log2(i+1);
00423 
00424         put_bits(pb, 2*e+1, i+1);
00425     }
00426 }
00427 
00431 static inline void set_te_golomb(PutBitContext *pb, int i, int range){
00432     assert(range >= 1);
00433     assert(i<=range);
00434 
00435     if(range==2) put_bits(pb, 1, i^1);
00436     else         set_ue_golomb(pb, i);
00437 }
00438 
00442 static inline void set_se_golomb(PutBitContext *pb, int i){
00443 //    if (i>32767 || i<-32767)
00444 //        av_log(NULL,AV_LOG_ERROR,"value out of range %d\n", i);
00445 #if 0
00446     if(i<=0) i= -2*i;
00447     else     i=  2*i-1;
00448 #elif 1
00449     i= 2*i-1;
00450     if(i<0) i^= -1; //FIXME check if gcc does the right thing
00451 #else
00452     i= 2*i-1;
00453     i^= (i>>31);
00454 #endif
00455     set_ue_golomb(pb, i);
00456 }
00457 
00461 static inline void set_ur_golomb(PutBitContext *pb, int i, int k, int limit, int esc_len){
00462     int e;
00463 
00464     assert(i>=0);
00465 
00466     e= i>>k;
00467     if(e<limit){
00468         put_bits(pb, e + k + 1, (1<<k) + (i&((1<<k)-1)));
00469     }else{
00470         put_bits(pb, limit + esc_len, i - limit + 1);
00471     }
00472 }
00473 
00477 static inline void set_ur_golomb_jpegls(PutBitContext *pb, int i, int k, int limit, int esc_len){
00478     int e;
00479 
00480     assert(i>=0);
00481 
00482     e= (i>>k) + 1;
00483     if(e<limit){
00484         while(e > 31) {
00485             put_bits(pb, 31, 0);
00486             e -= 31;
00487         }
00488         put_bits(pb, e, 1);
00489         if(k)
00490             put_sbits(pb, k, i);
00491     }else{
00492         while(limit > 31) {
00493             put_bits(pb, 31, 0);
00494             limit -= 31;
00495         }
00496         put_bits(pb, limit  , 1);
00497         put_bits(pb, esc_len, i - 1);
00498     }
00499 }
00500 
00504 static inline void set_sr_golomb(PutBitContext *pb, int i, int k, int limit, int esc_len){
00505     int v;
00506 
00507     v = -2*i-1;
00508     v ^= (v>>31);
00509 
00510     set_ur_golomb(pb, v, k, limit, esc_len);
00511 }
00512 
00516 static inline void set_sr_golomb_flac(PutBitContext *pb, int i, int k, int limit, int esc_len){
00517     int v;
00518 
00519     v = -2*i-1;
00520     v ^= (v>>31);
00521 
00522     set_ur_golomb_jpegls(pb, v, k, limit, esc_len);
00523 }
00524 
00525 #endif /* AVCODEC_GOLOMB_H */