git.sesse.net Git - ffmpeg/blob - libavcodec/h264_cavlc.c

   1 /*
   2  * H.26L/H.264/AVC/JVT/14496-10/... cavlc bitstream decoding
   3  * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * FFmpeg is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 /**
  23  * @file libavcodec/h264_cavlc.c
  24  * H.264 / AVC / MPEG4 part10 cavlc bitstream decoding.
  25  * @author Michael Niedermayer <michaelni@gmx.at>
  26  */
  27
  28 #define CABAC 0
  29
  30 #include "internal.h"
  31 #include "avcodec.h"
  32 #include "mpegvideo.h"
  33 #include "h264.h"
  34 #include "h264data.h" // FIXME FIXME FIXME
  35 #include "h264_mvpred.h"
  36 #include "golomb.h"
  37
  38 //#undef NDEBUG
  39 #include <assert.h>
  40
  41 static const uint8_t golomb_to_inter_cbp_gray[16]={
  42  0, 1, 2, 4, 8, 3, 5,10,12,15, 7,11,13,14, 6, 9,
  43 };
  44
  45 static const uint8_t golomb_to_intra4x4_cbp_gray[16]={
  46 15, 0, 7,11,13,14, 3, 5,10,12, 1, 2, 4, 8, 6, 9,
  47 };
  48
  49 static const uint8_t chroma_dc_coeff_token_len[4*5]={
  50  2, 0, 0, 0,
  51  6, 1, 0, 0,
  52  6, 6, 3, 0,
  53  6, 7, 7, 6,
  54  6, 8, 8, 7,
  55 };
  56
  57 static const uint8_t chroma_dc_coeff_token_bits[4*5]={
  58  1, 0, 0, 0,
  59  7, 1, 0, 0,
  60  4, 6, 1, 0,
  61  3, 3, 2, 5,
  62  2, 3, 2, 0,
  63 };
  64
  65 static const uint8_t coeff_token_len[4][4*17]={
  66 {
  67      1, 0, 0, 0,
  68      6, 2, 0, 0,     8, 6, 3, 0,     9, 8, 7, 5,    10, 9, 8, 6,
  69     11,10, 9, 7,    13,11,10, 8,    13,13,11, 9,    13,13,13,10,
  70     14,14,13,11,    14,14,14,13,    15,15,14,14,    15,15,15,14,
  71     16,15,15,15,    16,16,16,15,    16,16,16,16,    16,16,16,16,
  72 },
  73 {
  74      2, 0, 0, 0,
  75      6, 2, 0, 0,     6, 5, 3, 0,     7, 6, 6, 4,     8, 6, 6, 4,
  76      8, 7, 7, 5,     9, 8, 8, 6,    11, 9, 9, 6,    11,11,11, 7,
  77     12,11,11, 9,    12,12,12,11,    12,12,12,11,    13,13,13,12,
  78     13,13,13,13,    13,14,13,13,    14,14,14,13,    14,14,14,14,
  79 },
  80 {
  81      4, 0, 0, 0,
  82      6, 4, 0, 0,     6, 5, 4, 0,     6, 5, 5, 4,     7, 5, 5, 4,
  83      7, 5, 5, 4,     7, 6, 6, 4,     7, 6, 6, 4,     8, 7, 7, 5,
  84      8, 8, 7, 6,     9, 8, 8, 7,     9, 9, 8, 8,     9, 9, 9, 8,
  85     10, 9, 9, 9,    10,10,10,10,    10,10,10,10,    10,10,10,10,
  86 },
  87 {
  88      6, 0, 0, 0,
  89      6, 6, 0, 0,     6, 6, 6, 0,     6, 6, 6, 6,     6, 6, 6, 6,
  90      6, 6, 6, 6,     6, 6, 6, 6,     6, 6, 6, 6,     6, 6, 6, 6,
  91      6, 6, 6, 6,     6, 6, 6, 6,     6, 6, 6, 6,     6, 6, 6, 6,
  92      6, 6, 6, 6,     6, 6, 6, 6,     6, 6, 6, 6,     6, 6, 6, 6,
  93 }
  94 };
  95
  96 static const uint8_t coeff_token_bits[4][4*17]={
  97 {
  98      1, 0, 0, 0,
  99      5, 1, 0, 0,     7, 4, 1, 0,     7, 6, 5, 3,     7, 6, 5, 3,
 100      7, 6, 5, 4,    15, 6, 5, 4,    11,14, 5, 4,     8,10,13, 4,
 101     15,14, 9, 4,    11,10,13,12,    15,14, 9,12,    11,10,13, 8,
 102     15, 1, 9,12,    11,14,13, 8,     7,10, 9,12,     4, 6, 5, 8,
 103 },
 104 {
 105      3, 0, 0, 0,
 106     11, 2, 0, 0,     7, 7, 3, 0,     7,10, 9, 5,     7, 6, 5, 4,
 107      4, 6, 5, 6,     7, 6, 5, 8,    15, 6, 5, 4,    11,14,13, 4,
 108     15,10, 9, 4,    11,14,13,12,     8,10, 9, 8,    15,14,13,12,
 109     11,10, 9,12,     7,11, 6, 8,     9, 8,10, 1,     7, 6, 5, 4,
 110 },
 111 {
 112     15, 0, 0, 0,
 113     15,14, 0, 0,    11,15,13, 0,     8,12,14,12,    15,10,11,11,
 114     11, 8, 9,10,     9,14,13, 9,     8,10, 9, 8,    15,14,13,13,
 115     11,14,10,12,    15,10,13,12,    11,14, 9,12,     8,10,13, 8,
 116     13, 7, 9,12,     9,12,11,10,     5, 8, 7, 6,     1, 4, 3, 2,
 117 },
 118 {
 119      3, 0, 0, 0,
 120      0, 1, 0, 0,     4, 5, 6, 0,     8, 9,10,11,    12,13,14,15,
 121     16,17,18,19,    20,21,22,23,    24,25,26,27,    28,29,30,31,
 122     32,33,34,35,    36,37,38,39,    40,41,42,43,    44,45,46,47,
 123     48,49,50,51,    52,53,54,55,    56,57,58,59,    60,61,62,63,
 124 }
 125 };
 126
 127 static const uint8_t total_zeros_len[16][16]= {
 128     {1,3,3,4,4,5,5,6,6,7,7,8,8,9,9,9},
 129     {3,3,3,3,3,4,4,4,4,5,5,6,6,6,6},
 130     {4,3,3,3,4,4,3,3,4,5,5,6,5,6},
 131     {5,3,4,4,3,3,3,4,3,4,5,5,5},
 132     {4,4,4,3,3,3,3,3,4,5,4,5},
 133     {6,5,3,3,3,3,3,3,4,3,6},
 134     {6,5,3,3,3,2,3,4,3,6},
 135     {6,4,5,3,2,2,3,3,6},
 136     {6,6,4,2,2,3,2,5},
 137     {5,5,3,2,2,2,4},
 138     {4,4,3,3,1,3},
 139     {4,4,2,1,3},
 140     {3,3,1,2},
 141     {2,2,1},
 142     {1,1},
 143 };
 144
 145 static const uint8_t total_zeros_bits[16][16]= {
 146     {1,3,2,3,2,3,2,3,2,3,2,3,2,3,2,1},
 147     {7,6,5,4,3,5,4,3,2,3,2,3,2,1,0},
 148     {5,7,6,5,4,3,4,3,2,3,2,1,1,0},
 149     {3,7,5,4,6,5,4,3,3,2,2,1,0},
 150     {5,4,3,7,6,5,4,3,2,1,1,0},
 151     {1,1,7,6,5,4,3,2,1,1,0},
 152     {1,1,5,4,3,3,2,1,1,0},
 153     {1,1,1,3,3,2,2,1,0},
 154     {1,0,1,3,2,1,1,1},
 155     {1,0,1,3,2,1,1},
 156     {0,1,1,2,1,3},
 157     {0,1,1,1,1},
 158     {0,1,1,1},
 159     {0,1,1},
 160     {0,1},
 161 };
 162
 163 static const uint8_t chroma_dc_total_zeros_len[3][4]= {
 164     { 1, 2, 3, 3,},
 165     { 1, 2, 2, 0,},
 166     { 1, 1, 0, 0,},
 167 };
 168
 169 static const uint8_t chroma_dc_total_zeros_bits[3][4]= {
 170     { 1, 1, 1, 0,},
 171     { 1, 1, 0, 0,},
 172     { 1, 0, 0, 0,},
 173 };
 174
 175 static const uint8_t run_len[7][16]={
 176     {1,1},
 177     {1,2,2},
 178     {2,2,2,2},
 179     {2,2,2,3,3},
 180     {2,2,3,3,3,3},
 181     {2,3,3,3,3,3,3},
 182     {3,3,3,3,3,3,3,4,5,6,7,8,9,10,11},
 183 };
 184
 185 static const uint8_t run_bits[7][16]={
 186     {1,0},
 187     {1,1,0},
 188     {3,2,1,0},
 189     {3,2,1,1,0},
 190     {3,2,3,2,1,0},
 191     {3,0,1,3,2,5,4},
 192     {7,6,5,4,3,2,1,1,1,1,1,1,1,1,1},
 193 };
 194
 195 static VLC coeff_token_vlc[4];
 196 static VLC_TYPE coeff_token_vlc_tables[520+332+280+256][2];
 197 static const int coeff_token_vlc_tables_size[4]={520,332,280,256};
 198
 199 static VLC chroma_dc_coeff_token_vlc;
 200 static VLC_TYPE chroma_dc_coeff_token_vlc_table[256][2];
 201 static const int chroma_dc_coeff_token_vlc_table_size = 256;
 202
 203 static VLC total_zeros_vlc[15];
 204 static VLC_TYPE total_zeros_vlc_tables[15][512][2];
 205 static const int total_zeros_vlc_tables_size = 512;
 206
 207 static VLC chroma_dc_total_zeros_vlc[3];
 208 static VLC_TYPE chroma_dc_total_zeros_vlc_tables[3][8][2];
 209 static const int chroma_dc_total_zeros_vlc_tables_size = 8;
 210
 211 static VLC run_vlc[6];
 212 static VLC_TYPE run_vlc_tables[6][8][2];
 213 static const int run_vlc_tables_size = 8;
 214
 215 static VLC run7_vlc;
 216 static VLC_TYPE run7_vlc_table[96][2];
 217 static const int run7_vlc_table_size = 96;
 218
 219 #define LEVEL_TAB_BITS 8
 220 static int8_t cavlc_level_tab[7][1<<LEVEL_TAB_BITS][2];
 221
 222
 223 /**
 224  * gets the predicted number of non-zero coefficients.
 225  * @param n block index
 226  */
 227 static inline int pred_non_zero_count(H264Context *h, int n){
 228     const int index8= scan8[n];
 229     const int left= h->non_zero_count_cache[index8 - 1];
 230     const int top = h->non_zero_count_cache[index8 - 8];
 231     int i= left + top;
 232
 233     if(i<64) i= (i+1)>>1;
 234
 235     tprintf(h->s.avctx, "pred_nnz L%X T%X n%d s%d P%X\n", left, top, n, scan8[n], i&31);
 236
 237     return i&31;
 238 }
 239
 240 static av_cold void init_cavlc_level_tab(void){
 241     int suffix_length, mask;
 242     unsigned int i;
 243
 244     for(suffix_length=0; suffix_length<7; suffix_length++){
 245         for(i=0; i<(1<<LEVEL_TAB_BITS); i++){
 246             int prefix= LEVEL_TAB_BITS - av_log2(2*i);
 247             int level_code= (prefix<<suffix_length) + (i>>(LEVEL_TAB_BITS-prefix-1-suffix_length)) - (1<<suffix_length);
 248
 249             mask= -(level_code&1);
 250             level_code= (((2+level_code)>>1) ^ mask) - mask;
 251             if(prefix + 1 + suffix_length <= LEVEL_TAB_BITS){
 252                 cavlc_level_tab[suffix_length][i][0]= level_code;
 253                 cavlc_level_tab[suffix_length][i][1]= prefix + 1 + suffix_length;
 254             }else if(prefix + 1 <= LEVEL_TAB_BITS){
 255                 cavlc_level_tab[suffix_length][i][0]= prefix+100;
 256                 cavlc_level_tab[suffix_length][i][1]= prefix + 1;
 257             }else{
 258                 cavlc_level_tab[suffix_length][i][0]= LEVEL_TAB_BITS+100;
 259                 cavlc_level_tab[suffix_length][i][1]= LEVEL_TAB_BITS;
 260             }
 261         }
 262     }
 263 }
 264
 265 av_cold void ff_h264_decode_init_vlc(void){
 266     static int done = 0;
 267
 268     if (!done) {
 269         int i;
 270         int offset;
 271         done = 1;
 272
 273         chroma_dc_coeff_token_vlc.table = chroma_dc_coeff_token_vlc_table;
 274         chroma_dc_coeff_token_vlc.table_allocated = chroma_dc_coeff_token_vlc_table_size;
 275         init_vlc(&chroma_dc_coeff_token_vlc, CHROMA_DC_COEFF_TOKEN_VLC_BITS, 4*5,
 276                  &chroma_dc_coeff_token_len [0], 1, 1,
 277                  &chroma_dc_coeff_token_bits[0], 1, 1,
 278                  INIT_VLC_USE_NEW_STATIC);
 279
 280         offset = 0;
 281         for(i=0; i<4; i++){
 282             coeff_token_vlc[i].table = coeff_token_vlc_tables+offset;
 283             coeff_token_vlc[i].table_allocated = coeff_token_vlc_tables_size[i];
 284             init_vlc(&coeff_token_vlc[i], COEFF_TOKEN_VLC_BITS, 4*17,
 285                      &coeff_token_len [i][0], 1, 1,
 286                      &coeff_token_bits[i][0], 1, 1,
 287                      INIT_VLC_USE_NEW_STATIC);
 288             offset += coeff_token_vlc_tables_size[i];
 289         }
 290         /*
 291          * This is a one time safety check to make sure that
 292          * the packed static coeff_token_vlc table sizes
 293          * were initialized correctly.
 294          */
 295         assert(offset == FF_ARRAY_ELEMS(coeff_token_vlc_tables));
 296
 297         for(i=0; i<3; i++){
 298             chroma_dc_total_zeros_vlc[i].table = chroma_dc_total_zeros_vlc_tables[i];
 299             chroma_dc_total_zeros_vlc[i].table_allocated = chroma_dc_total_zeros_vlc_tables_size;
 300             init_vlc(&chroma_dc_total_zeros_vlc[i],
 301                      CHROMA_DC_TOTAL_ZEROS_VLC_BITS, 4,
 302                      &chroma_dc_total_zeros_len [i][0], 1, 1,
 303                      &chroma_dc_total_zeros_bits[i][0], 1, 1,
 304                      INIT_VLC_USE_NEW_STATIC);
 305         }
 306         for(i=0; i<15; i++){
 307             total_zeros_vlc[i].table = total_zeros_vlc_tables[i];
 308             total_zeros_vlc[i].table_allocated = total_zeros_vlc_tables_size;
 309             init_vlc(&total_zeros_vlc[i],
 310                      TOTAL_ZEROS_VLC_BITS, 16,
 311                      &total_zeros_len [i][0], 1, 1,
 312                      &total_zeros_bits[i][0], 1, 1,
 313                      INIT_VLC_USE_NEW_STATIC);
 314         }
 315
 316         for(i=0; i<6; i++){
 317             run_vlc[i].table = run_vlc_tables[i];
 318             run_vlc[i].table_allocated = run_vlc_tables_size;
 319             init_vlc(&run_vlc[i],
 320                      RUN_VLC_BITS, 7,
 321                      &run_len [i][0], 1, 1,
 322                      &run_bits[i][0], 1, 1,
 323                      INIT_VLC_USE_NEW_STATIC);
 324         }
 325         run7_vlc.table = run7_vlc_table,
 326         run7_vlc.table_allocated = run7_vlc_table_size;
 327         init_vlc(&run7_vlc, RUN7_VLC_BITS, 16,
 328                  &run_len [6][0], 1, 1,
 329                  &run_bits[6][0], 1, 1,
 330                  INIT_VLC_USE_NEW_STATIC);
 331
 332         init_cavlc_level_tab();
 333     }
 334 }
 335
 336 /**
 337  *
 338  */
 339 static inline int get_level_prefix(GetBitContext *gb){
 340     unsigned int buf;
 341     int log;
 342
 343     OPEN_READER(re, gb);
 344     UPDATE_CACHE(re, gb);
 345     buf=GET_CACHE(re, gb);
 346
 347     log= 32 - av_log2(buf);
 348 #ifdef TRACE
 349     print_bin(buf>>(32-log), log);
 350     av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d lpr @%5d in %s get_level_prefix\n", buf>>(32-log), log, log-1, get_bits_count(gb), __FILE__);
 351 #endif
 352
 353     LAST_SKIP_BITS(re, gb, log);
 354     CLOSE_READER(re, gb);
 355
 356     return log-1;
 357 }
 358
 359 /**
 360  * decodes a residual block.
 361  * @param n block index
 362  * @param scantable scantable
 363  * @param max_coeff number of coefficients in the block
 364  * @return <0 if an error occurred
 365  */
 366 static int decode_residual(H264Context *h, GetBitContext *gb, DCTELEM *block, int n, const uint8_t *scantable, const uint32_t *qmul, int max_coeff){
 367     MpegEncContext * const s = &h->s;
 368     static const int coeff_token_table_index[17]= {0, 0, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3};
 369     int level[16];
 370     int zeros_left, coeff_num, coeff_token, total_coeff, i, j, trailing_ones, run_before;
 371
 372     //FIXME put trailing_onex into the context
 373
 374     if(n == CHROMA_DC_BLOCK_INDEX){
 375         coeff_token= get_vlc2(gb, chroma_dc_coeff_token_vlc.table, CHROMA_DC_COEFF_TOKEN_VLC_BITS, 1);
 376         total_coeff= coeff_token>>2;
 377     }else{
 378         if(n == LUMA_DC_BLOCK_INDEX){
 379             total_coeff= pred_non_zero_count(h, 0);
 380             coeff_token= get_vlc2(gb, coeff_token_vlc[ coeff_token_table_index[total_coeff] ].table, COEFF_TOKEN_VLC_BITS, 2);
 381             total_coeff= coeff_token>>2;
 382         }else{
 383             total_coeff= pred_non_zero_count(h, n);
 384             coeff_token= get_vlc2(gb, coeff_token_vlc[ coeff_token_table_index[total_coeff] ].table, COEFF_TOKEN_VLC_BITS, 2);
 385             total_coeff= coeff_token>>2;
 386             h->non_zero_count_cache[ scan8[n] ]= total_coeff;
 387         }
 388     }
 389
 390     //FIXME set last_non_zero?
 391
 392     if(total_coeff==0)
 393         return 0;
 394     if(total_coeff > (unsigned)max_coeff) {
 395         av_log(h->s.avctx, AV_LOG_ERROR, "corrupted macroblock %d %d (total_coeff=%d)\n", s->mb_x, s->mb_y, total_coeff);
 396         return -1;
 397     }
 398
 399     trailing_ones= coeff_token&3;
 400     tprintf(h->s.avctx, "trailing:%d, total:%d\n", trailing_ones, total_coeff);
 401     assert(total_coeff<=16);
 402
 403     i = show_bits(gb, 3);
 404     skip_bits(gb, trailing_ones);
 405     level[0] = 1-((i&4)>>1);
 406     level[1] = 1-((i&2)   );
 407     level[2] = 1-((i&1)<<1);
 408
 409     if(trailing_ones<total_coeff) {
 410         int mask, prefix;
 411         int suffix_length = total_coeff > 10 & trailing_ones < 3;
 412         int bitsi= show_bits(gb, LEVEL_TAB_BITS);
 413         int level_code= cavlc_level_tab[suffix_length][bitsi][0];
 414
 415         skip_bits(gb, cavlc_level_tab[suffix_length][bitsi][1]);
 416         if(level_code >= 100){
 417             prefix= level_code - 100;
 418             if(prefix == LEVEL_TAB_BITS)
 419                 prefix += get_level_prefix(gb);
 420
 421             //first coefficient has suffix_length equal to 0 or 1
 422             if(prefix<14){ //FIXME try to build a large unified VLC table for all this
 423                 if(suffix_length)
 424                     level_code= (prefix<<1) + get_bits1(gb); //part
 425                 else
 426                     level_code= prefix; //part
 427             }else if(prefix==14){
 428                 if(suffix_length)
 429                     level_code= (prefix<<1) + get_bits1(gb); //part
 430                 else
 431                     level_code= prefix + get_bits(gb, 4); //part
 432             }else{
 433                 level_code= 30 + get_bits(gb, prefix-3); //part
 434                 if(prefix>=16)
 435                     level_code += (1<<(prefix-3))-4096;
 436             }
 437
 438             if(trailing_ones < 3) level_code += 2;
 439
 440             suffix_length = 2;
 441             mask= -(level_code&1);
 442             level[trailing_ones]= (((2+level_code)>>1) ^ mask) - mask;
 443         }else{
 444             level_code += ((level_code>>31)|1) & -(trailing_ones < 3);
 445
 446             suffix_length = 1 + (level_code + 3U > 6U);
 447             level[trailing_ones]= level_code;
 448         }
 449
 450         //remaining coefficients have suffix_length > 0
 451         for(i=trailing_ones+1;i<total_coeff;i++) {
 452             static const unsigned int suffix_limit[7] = {0,3,6,12,24,48,INT_MAX };
 453             int bitsi= show_bits(gb, LEVEL_TAB_BITS);
 454             level_code= cavlc_level_tab[suffix_length][bitsi][0];
 455
 456             skip_bits(gb, cavlc_level_tab[suffix_length][bitsi][1]);
 457             if(level_code >= 100){
 458                 prefix= level_code - 100;
 459                 if(prefix == LEVEL_TAB_BITS){
 460                     prefix += get_level_prefix(gb);
 461                 }
 462                 if(prefix<15){
 463                     level_code = (prefix<<suffix_length) + get_bits(gb, suffix_length);
 464                 }else{
 465                     level_code = (15<<suffix_length) + get_bits(gb, prefix-3);
 466                     if(prefix>=16)
 467                         level_code += (1<<(prefix-3))-4096;
 468                 }
 469                 mask= -(level_code&1);
 470                 level_code= (((2+level_code)>>1) ^ mask) - mask;
 471             }
 472             level[i]= level_code;
 473             suffix_length+= suffix_limit[suffix_length] + level_code > 2U*suffix_limit[suffix_length];
 474         }
 475     }
 476
 477     if(total_coeff == max_coeff)
 478         zeros_left=0;
 479     else{
 480         if(n == CHROMA_DC_BLOCK_INDEX)
 481             zeros_left= get_vlc2(gb, chroma_dc_total_zeros_vlc[ total_coeff-1 ].table, CHROMA_DC_TOTAL_ZEROS_VLC_BITS, 1);
 482         else
 483             zeros_left= get_vlc2(gb, total_zeros_vlc[ total_coeff-1 ].table, TOTAL_ZEROS_VLC_BITS, 1);
 484     }
 485
 486     coeff_num = zeros_left + total_coeff - 1;
 487     j = scantable[coeff_num];
 488     if(n > 24){
 489         block[j] = level[0];
 490         for(i=1;i<total_coeff;i++) {
 491             if(zeros_left <= 0)
 492                 run_before = 0;
 493             else if(zeros_left < 7){
 494                 run_before= get_vlc2(gb, run_vlc[zeros_left-1].table, RUN_VLC_BITS, 1);
 495             }else{
 496                 run_before= get_vlc2(gb, run7_vlc.table, RUN7_VLC_BITS, 2);
 497             }
 498             zeros_left -= run_before;
 499             coeff_num -= 1 + run_before;
 500             j= scantable[ coeff_num ];
 501
 502             block[j]= level[i];
 503         }
 504     }else{
 505         block[j] = (level[0] * qmul[j] + 32)>>6;
 506         for(i=1;i<total_coeff;i++) {
 507             if(zeros_left <= 0)
 508                 run_before = 0;
 509             else if(zeros_left < 7){
 510                 run_before= get_vlc2(gb, run_vlc[zeros_left-1].table, RUN_VLC_BITS, 1);
 511             }else{
 512                 run_before= get_vlc2(gb, run7_vlc.table, RUN7_VLC_BITS, 2);
 513             }
 514             zeros_left -= run_before;
 515             coeff_num -= 1 + run_before;
 516             j= scantable[ coeff_num ];
 517
 518             block[j]= (level[i] * qmul[j] + 32)>>6;
 519         }
 520     }
 521
 522     if(zeros_left<0){
 523         av_log(h->s.avctx, AV_LOG_ERROR, "negative number of zero coeffs at %d %d\n", s->mb_x, s->mb_y);
 524         return -1;
 525     }
 526
 527     return 0;
 528 }
 529
 530 int ff_h264_decode_mb_cavlc(H264Context *h){
 531     MpegEncContext * const s = &h->s;
 532     int mb_xy;
 533     int partition_count;
 534     unsigned int mb_type, cbp;
 535     int dct8x8_allowed= h->pps.transform_8x8_mode;
 536
 537     mb_xy = h->mb_xy = s->mb_x + s->mb_y*s->mb_stride;
 538
 539     tprintf(s->avctx, "pic:%d mb:%d/%d\n", h->frame_num, s->mb_x, s->mb_y);
 540     cbp = 0; /* avoid warning. FIXME: find a solution without slowing
 541                 down the code */
 542     if(h->slice_type_nos != FF_I_TYPE){
 543         if(s->mb_skip_run==-1)
 544             s->mb_skip_run= get_ue_golomb(&s->gb);
 545
 546         if (s->mb_skip_run--) {
 547             if(FRAME_MBAFF && (s->mb_y&1) == 0){
 548                 if(s->mb_skip_run==0)
 549                     h->mb_mbaff = h->mb_field_decoding_flag = get_bits1(&s->gb);
 550                 else
 551                     predict_field_decoding_flag(h);
 552             }
 553             decode_mb_skip(h);
 554             return 0;
 555         }
 556     }
 557     if(FRAME_MBAFF){
 558         if( (s->mb_y&1) == 0 )
 559             h->mb_mbaff = h->mb_field_decoding_flag = get_bits1(&s->gb);
 560     }
 561
 562     h->prev_mb_skipped= 0;
 563
 564     mb_type= get_ue_golomb(&s->gb);
 565     if(h->slice_type_nos == FF_B_TYPE){
 566         if(mb_type < 23){
 567             partition_count= b_mb_type_info[mb_type].partition_count;
 568             mb_type=         b_mb_type_info[mb_type].type;
 569         }else{
 570             mb_type -= 23;
 571             goto decode_intra_mb;
 572         }
 573     }else if(h->slice_type_nos == FF_P_TYPE){
 574         if(mb_type < 5){
 575             partition_count= p_mb_type_info[mb_type].partition_count;
 576             mb_type=         p_mb_type_info[mb_type].type;
 577         }else{
 578             mb_type -= 5;
 579             goto decode_intra_mb;
 580         }
 581     }else{
 582        assert(h->slice_type_nos == FF_I_TYPE);
 583         if(h->slice_type == FF_SI_TYPE && mb_type)
 584             mb_type--;
 585 decode_intra_mb:
 586         if(mb_type > 25){
 587             av_log(h->s.avctx, AV_LOG_ERROR, "mb_type %d in %c slice too large at %d %d\n", mb_type, av_get_pict_type_char(h->slice_type), s->mb_x, s->mb_y);
 588             return -1;
 589         }
 590         partition_count=0;
 591         cbp= i_mb_type_info[mb_type].cbp;
 592         h->intra16x16_pred_mode= i_mb_type_info[mb_type].pred_mode;
 593         mb_type= i_mb_type_info[mb_type].type;
 594     }
 595
 596     if(MB_FIELD)
 597         mb_type |= MB_TYPE_INTERLACED;
 598
 599     h->slice_table[ mb_xy ]= h->slice_num;
 600
 601     if(IS_INTRA_PCM(mb_type)){
 602         unsigned int x;
 603
 604         // We assume these blocks are very rare so we do not optimize it.
 605         align_get_bits(&s->gb);
 606
 607         // The pixels are stored in the same order as levels in h->mb array.
 608         for(x=0; x < (CHROMA ? 384 : 256); x++){
 609             ((uint8_t*)h->mb)[x]= get_bits(&s->gb, 8);
 610         }
 611
 612         // In deblocking, the quantizer is 0
 613         s->current_picture.qscale_table[mb_xy]= 0;
 614         // All coeffs are present
 615         memset(h->non_zero_count[mb_xy], 16, 32);
 616
 617         s->current_picture.mb_type[mb_xy]= mb_type;
 618         return 0;
 619     }
 620
 621     if(MB_MBAFF){
 622         h->ref_count[0] <<= 1;
 623         h->ref_count[1] <<= 1;
 624     }
 625
 626     fill_decode_caches(h, mb_type);
 627
 628     //mb_pred
 629     if(IS_INTRA(mb_type)){
 630         int pred_mode;
 631 //            init_top_left_availability(h);
 632         if(IS_INTRA4x4(mb_type)){
 633             int i;
 634             int di = 1;
 635             if(dct8x8_allowed && get_bits1(&s->gb)){
 636                 mb_type |= MB_TYPE_8x8DCT;
 637                 di = 4;
 638             }
 639
 640 //                fill_intra4x4_pred_table(h);
 641             for(i=0; i<16; i+=di){
 642                 int mode= pred_intra_mode(h, i);
 643
 644                 if(!get_bits1(&s->gb)){
 645                     const int rem_mode= get_bits(&s->gb, 3);
 646                     mode = rem_mode + (rem_mode >= mode);
 647                 }
 648
 649                 if(di==4)
 650                     fill_rectangle( &h->intra4x4_pred_mode_cache[ scan8[i] ], 2, 2, 8, mode, 1 );
 651                 else
 652                     h->intra4x4_pred_mode_cache[ scan8[i] ] = mode;
 653             }
 654             ff_h264_write_back_intra_pred_mode(h);
 655             if( ff_h264_check_intra4x4_pred_mode(h) < 0)
 656                 return -1;
 657         }else{
 658             h->intra16x16_pred_mode= ff_h264_check_intra_pred_mode(h, h->intra16x16_pred_mode);
 659             if(h->intra16x16_pred_mode < 0)
 660                 return -1;
 661         }
 662         if(CHROMA){
 663             pred_mode= ff_h264_check_intra_pred_mode(h, get_ue_golomb_31(&s->gb));
 664             if(pred_mode < 0)
 665                 return -1;
 666             h->chroma_pred_mode= pred_mode;
 667         }
 668     }else if(partition_count==4){
 669         int i, j, sub_partition_count[4], list, ref[2][4];
 670
 671         if(h->slice_type_nos == FF_B_TYPE){
 672             for(i=0; i<4; i++){
 673                 h->sub_mb_type[i]= get_ue_golomb_31(&s->gb);
 674                 if(h->sub_mb_type[i] >=13){
 675                     av_log(h->s.avctx, AV_LOG_ERROR, "B sub_mb_type %u out of range at %d %d\n", h->sub_mb_type[i], s->mb_x, s->mb_y);
 676                     return -1;
 677                 }
 678                 sub_partition_count[i]= b_sub_mb_type_info[ h->sub_mb_type[i] ].partition_count;
 679                 h->sub_mb_type[i]=      b_sub_mb_type_info[ h->sub_mb_type[i] ].type;
 680             }
 681             if( IS_DIRECT(h->sub_mb_type[0]|h->sub_mb_type[1]|h->sub_mb_type[2]|h->sub_mb_type[3])) {
 682                 ff_h264_pred_direct_motion(h, &mb_type);
 683                 h->ref_cache[0][scan8[4]] =
 684                 h->ref_cache[1][scan8[4]] =
 685                 h->ref_cache[0][scan8[12]] =
 686                 h->ref_cache[1][scan8[12]] = PART_NOT_AVAILABLE;
 687             }
 688         }else{
 689             assert(h->slice_type_nos == FF_P_TYPE); //FIXME SP correct ?
 690             for(i=0; i<4; i++){
 691                 h->sub_mb_type[i]= get_ue_golomb_31(&s->gb);
 692                 if(h->sub_mb_type[i] >=4){
 693                     av_log(h->s.avctx, AV_LOG_ERROR, "P sub_mb_type %u out of range at %d %d\n", h->sub_mb_type[i], s->mb_x, s->mb_y);
 694                     return -1;
 695                 }
 696                 sub_partition_count[i]= p_sub_mb_type_info[ h->sub_mb_type[i] ].partition_count;
 697                 h->sub_mb_type[i]=      p_sub_mb_type_info[ h->sub_mb_type[i] ].type;
 698             }
 699         }
 700
 701         for(list=0; list<h->list_count; list++){
 702             int ref_count= IS_REF0(mb_type) ? 1 : h->ref_count[list];
 703             for(i=0; i<4; i++){
 704                 if(IS_DIRECT(h->sub_mb_type[i])) continue;
 705                 if(IS_DIR(h->sub_mb_type[i], 0, list)){
 706                     unsigned int tmp;
 707                     if(ref_count == 1){
 708                         tmp= 0;
 709                     }else if(ref_count == 2){
 710                         tmp= get_bits1(&s->gb)^1;
 711                     }else{
 712                         tmp= get_ue_golomb_31(&s->gb);
 713                         if(tmp>=ref_count){
 714                             av_log(h->s.avctx, AV_LOG_ERROR, "ref %u overflow\n", tmp);
 715                             return -1;
 716                         }
 717                     }
 718                     ref[list][i]= tmp;
 719                 }else{
 720                  //FIXME
 721                     ref[list][i] = -1;
 722                 }
 723             }
 724         }
 725
 726         if(dct8x8_allowed)
 727             dct8x8_allowed = get_dct8x8_allowed(h);
 728
 729         for(list=0; list<h->list_count; list++){
 730             for(i=0; i<4; i++){
 731                 if(IS_DIRECT(h->sub_mb_type[i])) {
 732                     h->ref_cache[list][ scan8[4*i] ] = h->ref_cache[list][ scan8[4*i]+1 ];
 733                     continue;
 734                 }
 735                 h->ref_cache[list][ scan8[4*i]   ]=h->ref_cache[list][ scan8[4*i]+1 ]=
 736                 h->ref_cache[list][ scan8[4*i]+8 ]=h->ref_cache[list][ scan8[4*i]+9 ]= ref[list][i];
 737
 738                 if(IS_DIR(h->sub_mb_type[i], 0, list)){
 739                     const int sub_mb_type= h->sub_mb_type[i];
 740                     const int block_width= (sub_mb_type & (MB_TYPE_16x16|MB_TYPE_16x8)) ? 2 : 1;
 741                     for(j=0; j<sub_partition_count[i]; j++){
 742                         int mx, my;
 743                         const int index= 4*i + block_width*j;
 744                         int16_t (* mv_cache)[2]= &h->mv_cache[list][ scan8[index] ];
 745                         pred_motion(h, index, block_width, list, h->ref_cache[list][ scan8[index] ], &mx, &my);
 746                         mx += get_se_golomb(&s->gb);
 747                         my += get_se_golomb(&s->gb);
 748                         tprintf(s->avctx, "final mv:%d %d\n", mx, my);
 749
 750                         if(IS_SUB_8X8(sub_mb_type)){
 751                             mv_cache[ 1 ][0]=
 752                             mv_cache[ 8 ][0]= mv_cache[ 9 ][0]= mx;
 753                             mv_cache[ 1 ][1]=
 754                             mv_cache[ 8 ][1]= mv_cache[ 9 ][1]= my;
 755                         }else if(IS_SUB_8X4(sub_mb_type)){
 756                             mv_cache[ 1 ][0]= mx;
 757                             mv_cache[ 1 ][1]= my;
 758                         }else if(IS_SUB_4X8(sub_mb_type)){
 759                             mv_cache[ 8 ][0]= mx;
 760                             mv_cache[ 8 ][1]= my;
 761                         }
 762                         mv_cache[ 0 ][0]= mx;
 763                         mv_cache[ 0 ][1]= my;
 764                     }
 765                 }else{
 766                     uint32_t *p= (uint32_t *)&h->mv_cache[list][ scan8[4*i] ][0];
 767                     p[0] = p[1]=
 768                     p[8] = p[9]= 0;
 769                 }
 770             }
 771         }
 772     }else if(IS_DIRECT(mb_type)){
 773         ff_h264_pred_direct_motion(h, &mb_type);
 774         dct8x8_allowed &= h->sps.direct_8x8_inference_flag;
 775     }else{
 776         int list, mx, my, i;
 777          //FIXME we should set ref_idx_l? to 0 if we use that later ...
 778         if(IS_16X16(mb_type)){
 779             for(list=0; list<h->list_count; list++){
 780                     unsigned int val;
 781                     if(IS_DIR(mb_type, 0, list)){
 782                         if(h->ref_count[list]==1){
 783                             val= 0;
 784                         }else if(h->ref_count[list]==2){
 785                             val= get_bits1(&s->gb)^1;
 786                         }else{
 787                             val= get_ue_golomb_31(&s->gb);
 788                             if(val >= h->ref_count[list]){
 789                                 av_log(h->s.avctx, AV_LOG_ERROR, "ref %u overflow\n", val);
 790                                 return -1;
 791                             }
 792                         }
 793                     }else
 794                         val= LIST_NOT_USED&0xFF;
 795                     fill_rectangle(&h->ref_cache[list][ scan8[0] ], 4, 4, 8, val, 1);
 796             }
 797             for(list=0; list<h->list_count; list++){
 798                 unsigned int val;
 799                 if(IS_DIR(mb_type, 0, list)){
 800                     pred_motion(h, 0, 4, list, h->ref_cache[list][ scan8[0] ], &mx, &my);
 801                     mx += get_se_golomb(&s->gb);
 802                     my += get_se_golomb(&s->gb);
 803                     tprintf(s->avctx, "final mv:%d %d\n", mx, my);
 804
 805                     val= pack16to32(mx,my);
 806                 }else
 807                     val=0;
 808                 fill_rectangle(h->mv_cache[list][ scan8[0] ], 4, 4, 8, val, 4);
 809             }
 810         }
 811         else if(IS_16X8(mb_type)){
 812             for(list=0; list<h->list_count; list++){
 813                     for(i=0; i<2; i++){
 814                         unsigned int val;
 815                         if(IS_DIR(mb_type, i, list)){
 816                             if(h->ref_count[list] == 1){
 817                                 val= 0;
 818                             }else if(h->ref_count[list] == 2){
 819                                 val= get_bits1(&s->gb)^1;
 820                             }else{
 821                                 val= get_ue_golomb_31(&s->gb);
 822                                 if(val >= h->ref_count[list]){
 823                                     av_log(h->s.avctx, AV_LOG_ERROR, "ref %u overflow\n", val);
 824                                     return -1;
 825                                 }
 826                             }
 827                         }else
 828                             val= LIST_NOT_USED&0xFF;
 829                         fill_rectangle(&h->ref_cache[list][ scan8[0] + 16*i ], 4, 2, 8, val, 1);
 830                     }
 831             }
 832             for(list=0; list<h->list_count; list++){
 833                 for(i=0; i<2; i++){
 834                     unsigned int val;
 835                     if(IS_DIR(mb_type, i, list)){
 836                         pred_16x8_motion(h, 8*i, list, h->ref_cache[list][scan8[0] + 16*i], &mx, &my);
 837                         mx += get_se_golomb(&s->gb);
 838                         my += get_se_golomb(&s->gb);
 839                         tprintf(s->avctx, "final mv:%d %d\n", mx, my);
 840
 841                         val= pack16to32(mx,my);
 842                     }else
 843                         val=0;
 844                     fill_rectangle(h->mv_cache[list][ scan8[0] + 16*i ], 4, 2, 8, val, 4);
 845                 }
 846             }
 847         }else{
 848             assert(IS_8X16(mb_type));
 849             for(list=0; list<h->list_count; list++){
 850                     for(i=0; i<2; i++){
 851                         unsigned int val;
 852                         if(IS_DIR(mb_type, i, list)){ //FIXME optimize
 853                             if(h->ref_count[list]==1){
 854                                 val= 0;
 855                             }else if(h->ref_count[list]==2){
 856                                 val= get_bits1(&s->gb)^1;
 857                             }else{
 858                                 val= get_ue_golomb_31(&s->gb);
 859                                 if(val >= h->ref_count[list]){
 860                                     av_log(h->s.avctx, AV_LOG_ERROR, "ref %u overflow\n", val);
 861                                     return -1;
 862                                 }
 863                             }
 864                         }else
 865                             val= LIST_NOT_USED&0xFF;
 866                         fill_rectangle(&h->ref_cache[list][ scan8[0] + 2*i ], 2, 4, 8, val, 1);
 867                     }
 868             }
 869             for(list=0; list<h->list_count; list++){
 870                 for(i=0; i<2; i++){
 871                     unsigned int val;
 872                     if(IS_DIR(mb_type, i, list)){
 873                         pred_8x16_motion(h, i*4, list, h->ref_cache[list][ scan8[0] + 2*i ], &mx, &my);
 874                         mx += get_se_golomb(&s->gb);
 875                         my += get_se_golomb(&s->gb);
 876                         tprintf(s->avctx, "final mv:%d %d\n", mx, my);
 877
 878                         val= pack16to32(mx,my);
 879                     }else
 880                         val=0;
 881                     fill_rectangle(h->mv_cache[list][ scan8[0] + 2*i ], 2, 4, 8, val, 4);
 882                 }
 883             }
 884         }
 885     }
 886
 887     if(IS_INTER(mb_type))
 888         write_back_motion(h, mb_type);
 889
 890     if(!IS_INTRA16x16(mb_type)){
 891         cbp= get_ue_golomb(&s->gb);
 892         if(cbp > 47){
 893             av_log(h->s.avctx, AV_LOG_ERROR, "cbp too large (%u) at %d %d\n", cbp, s->mb_x, s->mb_y);
 894             return -1;
 895         }
 896
 897         if(CHROMA){
 898             if(IS_INTRA4x4(mb_type)) cbp= golomb_to_intra4x4_cbp[cbp];
 899             else                     cbp= golomb_to_inter_cbp   [cbp];
 900         }else{
 901             if(IS_INTRA4x4(mb_type)) cbp= golomb_to_intra4x4_cbp_gray[cbp];
 902             else                     cbp= golomb_to_inter_cbp_gray[cbp];
 903         }
 904     }
 905
 906     if(dct8x8_allowed && (cbp&15) && !IS_INTRA(mb_type)){
 907         if(get_bits1(&s->gb)){
 908             mb_type |= MB_TYPE_8x8DCT;
 909         }
 910     }
 911     h->cbp=
 912     h->cbp_table[mb_xy]= cbp;
 913     s->current_picture.mb_type[mb_xy]= mb_type;
 914
 915     if(cbp || IS_INTRA16x16(mb_type)){
 916         int i8x8, i4x4, chroma_idx;
 917         int dquant;
 918         GetBitContext *gb= IS_INTRA(mb_type) ? h->intra_gb_ptr : h->inter_gb_ptr;
 919         const uint8_t *scan, *scan8x8, *dc_scan;
 920
 921 //        fill_non_zero_count_cache(h);
 922
 923         if(IS_INTERLACED(mb_type)){
 924             scan8x8= s->qscale ? h->field_scan8x8_cavlc : h->field_scan8x8_cavlc_q0;
 925             scan= s->qscale ? h->field_scan : h->field_scan_q0;
 926             dc_scan= luma_dc_field_scan;
 927         }else{
 928             scan8x8= s->qscale ? h->zigzag_scan8x8_cavlc : h->zigzag_scan8x8_cavlc_q0;
 929             scan= s->qscale ? h->zigzag_scan : h->zigzag_scan_q0;
 930             dc_scan= luma_dc_zigzag_scan;
 931         }
 932
 933         dquant= get_se_golomb(&s->gb);
 934
 935         s->qscale += dquant;
 936
 937         if(((unsigned)s->qscale) > 51){
 938             if(s->qscale<0) s->qscale+= 52;
 939             else            s->qscale-= 52;
 940             if(((unsigned)s->qscale) > 51){
 941                 av_log(h->s.avctx, AV_LOG_ERROR, "dquant out of range (%d) at %d %d\n", dquant, s->mb_x, s->mb_y);
 942                 return -1;
 943             }
 944         }
 945
 946         h->chroma_qp[0]= get_chroma_qp(h, 0, s->qscale);
 947         h->chroma_qp[1]= get_chroma_qp(h, 1, s->qscale);
 948         if(IS_INTRA16x16(mb_type)){
 949             if( decode_residual(h, h->intra_gb_ptr, h->mb, LUMA_DC_BLOCK_INDEX, dc_scan, h->dequant4_coeff[0][s->qscale], 16) < 0){
 950                 return -1; //FIXME continue if partitioned and other return -1 too
 951             }
 952
 953             assert((cbp&15) == 0 || (cbp&15) == 15);
 954
 955             if(cbp&15){
 956                 for(i8x8=0; i8x8<4; i8x8++){
 957                     for(i4x4=0; i4x4<4; i4x4++){
 958                         const int index= i4x4 + 4*i8x8;
 959                         if( decode_residual(h, h->intra_gb_ptr, h->mb + 16*index, index, scan + 1, h->dequant4_coeff[0][s->qscale], 15) < 0 ){
 960                             return -1;
 961                         }
 962                     }
 963                 }
 964             }else{
 965                 fill_rectangle(&h->non_zero_count_cache[scan8[0]], 4, 4, 8, 0, 1);
 966             }
 967         }else{
 968             for(i8x8=0; i8x8<4; i8x8++){
 969                 if(cbp & (1<<i8x8)){
 970                     if(IS_8x8DCT(mb_type)){
 971                         DCTELEM *buf = &h->mb[64*i8x8];
 972                         uint8_t *nnz;
 973                         for(i4x4=0; i4x4<4; i4x4++){
 974                             if( decode_residual(h, gb, buf, i4x4+4*i8x8, scan8x8+16*i4x4,
 975                                                 h->dequant8_coeff[IS_INTRA( mb_type ) ? 0:1][s->qscale], 16) <0 )
 976                                 return -1;
 977                         }
 978                         nnz= &h->non_zero_count_cache[ scan8[4*i8x8] ];
 979                         nnz[0] += nnz[1] + nnz[8] + nnz[9];
 980                     }else{
 981                         for(i4x4=0; i4x4<4; i4x4++){
 982                             const int index= i4x4 + 4*i8x8;
 983
 984                             if( decode_residual(h, gb, h->mb + 16*index, index, scan, h->dequant4_coeff[IS_INTRA( mb_type ) ? 0:3][s->qscale], 16) <0 ){
 985                                 return -1;
 986                             }
 987                         }
 988                     }
 989                 }else{
 990                     uint8_t * const nnz= &h->non_zero_count_cache[ scan8[4*i8x8] ];
 991                     nnz[0] = nnz[1] = nnz[8] = nnz[9] = 0;
 992                 }
 993             }
 994         }
 995
 996         if(cbp&0x30){
 997             for(chroma_idx=0; chroma_idx<2; chroma_idx++)
 998                 if( decode_residual(h, gb, h->mb + 256 + 16*4*chroma_idx, CHROMA_DC_BLOCK_INDEX, chroma_dc_scan, NULL, 4) < 0){
 999                     return -1;
1000                 }
1001         }
1002
1003         if(cbp&0x20){
1004             for(chroma_idx=0; chroma_idx<2; chroma_idx++){
1005                 const uint32_t *qmul = h->dequant4_coeff[chroma_idx+1+(IS_INTRA( mb_type ) ? 0:3)][h->chroma_qp[chroma_idx]];
1006                 for(i4x4=0; i4x4<4; i4x4++){
1007                     const int index= 16 + 4*chroma_idx + i4x4;
1008                     if( decode_residual(h, gb, h->mb + 16*index, index, scan + 1, qmul, 15) < 0){
1009                         return -1;
1010                     }
1011                 }
1012             }
1013         }else{
1014             uint8_t * const nnz= &h->non_zero_count_cache[0];
1015             nnz[ scan8[16]+0 ] = nnz[ scan8[16]+1 ] =nnz[ scan8[16]+8 ] =nnz[ scan8[16]+9 ] =
1016             nnz[ scan8[20]+0 ] = nnz[ scan8[20]+1 ] =nnz[ scan8[20]+8 ] =nnz[ scan8[20]+9 ] = 0;
1017         }
1018     }else{
1019         uint8_t * const nnz= &h->non_zero_count_cache[0];
1020         fill_rectangle(&nnz[scan8[0]], 4, 4, 8, 0, 1);
1021         nnz[ scan8[16]+0 ] = nnz[ scan8[16]+1 ] =nnz[ scan8[16]+8 ] =nnz[ scan8[16]+9 ] =
1022         nnz[ scan8[20]+0 ] = nnz[ scan8[20]+1 ] =nnz[ scan8[20]+8 ] =nnz[ scan8[20]+9 ] = 0;
1023     }
1024     s->current_picture.qscale_table[mb_xy]= s->qscale;
1025     write_back_non_zero_count(h);
1026
1027     if(MB_MBAFF){
1028         h->ref_count[0] >>= 1;
1029         h->ref_count[1] >>= 1;
1030     }
1031
1032     return 0;
1033 }
1034