ffmpeg/libavcodec/h263.c

   1 /*
   2  * H263/MPEG4 backend for encoder and decoder
   3  * Copyright (c) 2000,2001 Fabrice Bellard
   4  * H263+ support.
   5  * Copyright (c) 2001 Juan J. Sierralta P
   6  * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
   7  *
   8  * This file is part of FFmpeg.
   9  *
  10  * FFmpeg is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU Lesser General Public
  12  * License as published by the Free Software Foundation; either
  13  * version 2.1 of the License, or (at your option) any later version.
  14  *
  15  * FFmpeg is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18  * Lesser General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU Lesser General Public
  21  * License along with FFmpeg; if not, write to the Free Software
  22  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  23  */
  24
  25 /**
  26  * @file
  27  * h263/mpeg4 codec.
  28  */
  29
  30 #include <limits.h>
  31
  32 #include "avcodec.h"
  33 #include "mpegvideo.h"
  34 #include "h263.h"
  35 #include "h263data.h"
  36 #include "mathops.h"
  37 #include "mpegutils.h"
  38 #include "unary.h"
  39 #include "flv.h"
  40 #include "mpeg4video.h"
  41
  42
  43 uint8_t ff_h263_static_rl_table_store[2][2][2*MAX_RUN + MAX_LEVEL + 3];
  44
  45
  46 void ff_h263_update_motion_val(MpegEncContext * s){
  47     const int mb_xy = s->mb_y * s->mb_stride + s->mb_x;
  48                //FIXME a lot of that is only needed for !low_delay
  49     const int wrap = s->b8_stride;
  50     const int xy = s->block_index[0];
  51
  52     s->current_picture.mbskip_table[mb_xy] = s->mb_skipped;
  53
  54     if(s->mv_type != MV_TYPE_8X8){
  55         int motion_x, motion_y;
  56         if (s->mb_intra) {
  57             motion_x = 0;
  58             motion_y = 0;
  59         } else if (s->mv_type == MV_TYPE_16X16) {
  60             motion_x = s->mv[0][0][0];
  61             motion_y = s->mv[0][0][1];
  62         } else /*if (s->mv_type == MV_TYPE_FIELD)*/ {
  63             int i;
  64             motion_x = s->mv[0][0][0] + s->mv[0][1][0];
  65             motion_y = s->mv[0][0][1] + s->mv[0][1][1];
  66             motion_x = (motion_x>>1) | (motion_x&1);
  67             for(i=0; i<2; i++){
  68                 s->p_field_mv_table[i][0][mb_xy][0]= s->mv[0][i][0];
  69                 s->p_field_mv_table[i][0][mb_xy][1]= s->mv[0][i][1];
  70             }
  71             s->current_picture.ref_index[0][4*mb_xy    ] =
  72             s->current_picture.ref_index[0][4*mb_xy + 1] = s->field_select[0][0];
  73             s->current_picture.ref_index[0][4*mb_xy + 2] =
  74             s->current_picture.ref_index[0][4*mb_xy + 3] = s->field_select[0][1];
  75         }
  76
  77         /* no update if 8X8 because it has been done during parsing */
  78         s->current_picture.motion_val[0][xy][0]            = motion_x;
  79         s->current_picture.motion_val[0][xy][1]            = motion_y;
  80         s->current_picture.motion_val[0][xy + 1][0]        = motion_x;
  81         s->current_picture.motion_val[0][xy + 1][1]        = motion_y;
  82         s->current_picture.motion_val[0][xy + wrap][0]     = motion_x;
  83         s->current_picture.motion_val[0][xy + wrap][1]     = motion_y;
  84         s->current_picture.motion_val[0][xy + 1 + wrap][0] = motion_x;
  85         s->current_picture.motion_val[0][xy + 1 + wrap][1] = motion_y;
  86     }
  87
  88     if(s->encoding){ //FIXME encoding MUST be cleaned up
  89         if (s->mv_type == MV_TYPE_8X8)
  90             s->current_picture.mb_type[mb_xy] = MB_TYPE_L0 | MB_TYPE_8x8;
  91         else if(s->mb_intra)
  92             s->current_picture.mb_type[mb_xy] = MB_TYPE_INTRA;
  93         else
  94             s->current_picture.mb_type[mb_xy] = MB_TYPE_L0 | MB_TYPE_16x16;
  95     }
  96 }
  97
  98 int ff_h263_pred_dc(MpegEncContext * s, int n, int16_t **dc_val_ptr)
  99 {
 100     int x, y, wrap, a, c, pred_dc;
 101     int16_t *dc_val;
 102
 103     /* find prediction */
 104     if (n < 4) {
 105         x = 2 * s->mb_x + (n & 1);
 106         y = 2 * s->mb_y + ((n & 2) >> 1);
 107         wrap = s->b8_stride;
 108         dc_val = s->dc_val[0];
 109     } else {
 110         x = s->mb_x;
 111         y = s->mb_y;
 112         wrap = s->mb_stride;
 113         dc_val = s->dc_val[n - 4 + 1];
 114     }
 115     /* B C
 116      * A X
 117      */
 118     a = dc_val[(x - 1) + (y) * wrap];
 119     c = dc_val[(x) + (y - 1) * wrap];
 120
 121     /* No prediction outside GOB boundary */
 122     if(s->first_slice_line && n!=3){
 123         if(n!=2) c= 1024;
 124         if(n!=1 && s->mb_x == s->resync_mb_x) a= 1024;
 125     }
 126     /* just DC prediction */
 127     if (a != 1024 && c != 1024)
 128         pred_dc = (a + c) >> 1;
 129     else if (a != 1024)
 130         pred_dc = a;
 131     else
 132         pred_dc = c;
 133
 134     /* we assume pred is positive */
 135     *dc_val_ptr = &dc_val[x + y * wrap];
 136     return pred_dc;
 137 }
 138
 139 void ff_h263_loop_filter(MpegEncContext * s){
 140     int qp_c;
 141     const int linesize  = s->linesize;
 142     const int uvlinesize= s->uvlinesize;
 143     const int xy = s->mb_y * s->mb_stride + s->mb_x;
 144     uint8_t *dest_y = s->dest[0];
 145     uint8_t *dest_cb= s->dest[1];
 146     uint8_t *dest_cr= s->dest[2];
 147
 148 //    if(s->pict_type==AV_PICTURE_TYPE_B && !s->readable) return;
 149
 150     /*
 151        Diag Top
 152        Left Center
 153     */
 154     if (!IS_SKIP(s->current_picture.mb_type[xy])) {
 155         qp_c= s->qscale;
 156         s->h263dsp.h263_v_loop_filter(dest_y + 8 * linesize,     linesize, qp_c);
 157         s->h263dsp.h263_v_loop_filter(dest_y + 8 * linesize + 8, linesize, qp_c);
 158     }else
 159         qp_c= 0;
 160
 161     if(s->mb_y){
 162         int qp_dt, qp_tt, qp_tc;
 163
 164         if (IS_SKIP(s->current_picture.mb_type[xy - s->mb_stride]))
 165             qp_tt=0;
 166         else
 167             qp_tt = s->current_picture.qscale_table[xy - s->mb_stride];
 168
 169         if(qp_c)
 170             qp_tc= qp_c;
 171         else
 172             qp_tc= qp_tt;
 173
 174         if(qp_tc){
 175             const int chroma_qp= s->chroma_qscale_table[qp_tc];
 176             s->h263dsp.h263_v_loop_filter(dest_y,     linesize, qp_tc);
 177             s->h263dsp.h263_v_loop_filter(dest_y + 8, linesize, qp_tc);
 178
 179             s->h263dsp.h263_v_loop_filter(dest_cb, uvlinesize, chroma_qp);
 180             s->h263dsp.h263_v_loop_filter(dest_cr, uvlinesize, chroma_qp);
 181         }
 182
 183         if(qp_tt)
 184             s->h263dsp.h263_h_loop_filter(dest_y - 8 * linesize + 8, linesize, qp_tt);
 185
 186         if(s->mb_x){
 187             if (qp_tt || IS_SKIP(s->current_picture.mb_type[xy - 1 - s->mb_stride]))
 188                 qp_dt= qp_tt;
 189             else
 190                 qp_dt = s->current_picture.qscale_table[xy - 1 - s->mb_stride];
 191
 192             if(qp_dt){
 193                 const int chroma_qp= s->chroma_qscale_table[qp_dt];
 194                 s->h263dsp.h263_h_loop_filter(dest_y  - 8 * linesize,   linesize,   qp_dt);
 195                 s->h263dsp.h263_h_loop_filter(dest_cb - 8 * uvlinesize, uvlinesize, chroma_qp);
 196                 s->h263dsp.h263_h_loop_filter(dest_cr - 8 * uvlinesize, uvlinesize, chroma_qp);
 197             }
 198         }
 199     }
 200
 201     if(qp_c){
 202         s->h263dsp.h263_h_loop_filter(dest_y + 8, linesize, qp_c);
 203         if(s->mb_y + 1 == s->mb_height)
 204             s->h263dsp.h263_h_loop_filter(dest_y + 8 * linesize + 8, linesize, qp_c);
 205     }
 206
 207     if(s->mb_x){
 208         int qp_lc;
 209         if (qp_c || IS_SKIP(s->current_picture.mb_type[xy - 1]))
 210             qp_lc= qp_c;
 211         else
 212             qp_lc = s->current_picture.qscale_table[xy - 1];
 213
 214         if(qp_lc){
 215             s->h263dsp.h263_h_loop_filter(dest_y, linesize, qp_lc);
 216             if(s->mb_y + 1 == s->mb_height){
 217                 const int chroma_qp= s->chroma_qscale_table[qp_lc];
 218                 s->h263dsp.h263_h_loop_filter(dest_y + 8 * linesize, linesize, qp_lc);
 219                 s->h263dsp.h263_h_loop_filter(dest_cb, uvlinesize, chroma_qp);
 220                 s->h263dsp.h263_h_loop_filter(dest_cr, uvlinesize, chroma_qp);
 221             }
 222         }
 223     }
 224 }
 225
 226 void ff_h263_pred_acdc(MpegEncContext * s, int16_t *block, int n)
 227 {
 228     int x, y, wrap, a, c, pred_dc, scale, i;
 229     int16_t *dc_val, *ac_val, *ac_val1;
 230
 231     /* find prediction */
 232     if (n < 4) {
 233         x = 2 * s->mb_x + (n & 1);
 234         y = 2 * s->mb_y + (n>> 1);
 235         wrap = s->b8_stride;
 236         dc_val = s->dc_val[0];
 237         ac_val = s->ac_val[0][0];
 238         scale = s->y_dc_scale;
 239     } else {
 240         x = s->mb_x;
 241         y = s->mb_y;
 242         wrap = s->mb_stride;
 243         dc_val = s->dc_val[n - 4 + 1];
 244         ac_val = s->ac_val[n - 4 + 1][0];
 245         scale = s->c_dc_scale;
 246     }
 247
 248     ac_val += ((y) * wrap + (x)) * 16;
 249     ac_val1 = ac_val;
 250
 251     /* B C
 252      * A X
 253      */
 254     a = dc_val[(x - 1) + (y) * wrap];
 255     c = dc_val[(x) + (y - 1) * wrap];
 256
 257     /* No prediction outside GOB boundary */
 258     if(s->first_slice_line && n!=3){
 259         if(n!=2) c= 1024;
 260         if(n!=1 && s->mb_x == s->resync_mb_x) a= 1024;
 261     }
 262
 263     if (s->ac_pred) {
 264         pred_dc = 1024;
 265         if (s->h263_aic_dir) {
 266             /* left prediction */
 267             if (a != 1024) {
 268                 ac_val -= 16;
 269                 for(i=1;i<8;i++) {
 270                     block[s->idsp.idct_permutation[i << 3]] += ac_val[i];
 271                 }
 272                 pred_dc = a;
 273             }
 274         } else {
 275             /* top prediction */
 276             if (c != 1024) {
 277                 ac_val -= 16 * wrap;
 278                 for(i=1;i<8;i++) {
 279                     block[s->idsp.idct_permutation[i]] += ac_val[i + 8];
 280                 }
 281                 pred_dc = c;
 282             }
 283         }
 284     } else {
 285         /* just DC prediction */
 286         if (a != 1024 && c != 1024)
 287             pred_dc = (a + c) >> 1;
 288         else if (a != 1024)
 289             pred_dc = a;
 290         else
 291             pred_dc = c;
 292     }
 293
 294     /* we assume pred is positive */
 295     block[0]=block[0]*scale + pred_dc;
 296
 297     if (block[0] < 0)
 298         block[0] = 0;
 299     else
 300         block[0] |= 1;
 301
 302     /* Update AC/DC tables */
 303     dc_val[(x) + (y) * wrap] = block[0];
 304
 305     /* left copy */
 306     for(i=1;i<8;i++)
 307         ac_val1[i]     = block[s->idsp.idct_permutation[i << 3]];
 308     /* top copy */
 309     for(i=1;i<8;i++)
 310         ac_val1[8 + i] = block[s->idsp.idct_permutation[i]];
 311 }
 312
 313 int16_t *ff_h263_pred_motion(MpegEncContext * s, int block, int dir,
 314                              int *px, int *py)
 315 {
 316     int wrap;
 317     int16_t *A, *B, *C, (*mot_val)[2];
 318     static const int off[4]= {2, 1, 1, -1};
 319
 320     wrap = s->b8_stride;
 321     mot_val = s->current_picture.motion_val[dir] + s->block_index[block];
 322
 323     A = mot_val[ - 1];
 324     /* special case for first (slice) line */
 325     if (s->first_slice_line && block<3) {
 326         // we can't just change some MVs to simulate that as we need them for the B frames (and ME)
 327         // and if we ever support non rectangular objects than we need to do a few ifs here anyway :(
 328         if(block==0){ //most common case
 329             if(s->mb_x  == s->resync_mb_x){ //rare
 330                 *px= *py = 0;
 331             }else if(s->mb_x + 1 == s->resync_mb_x && s->h263_pred){ //rare
 332                 C = mot_val[off[block] - wrap];
 333                 if(s->mb_x==0){
 334                     *px = C[0];
 335                     *py = C[1];
 336                 }else{
 337                     *px = mid_pred(A[0], 0, C[0]);
 338                     *py = mid_pred(A[1], 0, C[1]);
 339                 }
 340             }else{
 341                 *px = A[0];
 342                 *py = A[1];
 343             }
 344         }else if(block==1){
 345             if(s->mb_x + 1 == s->resync_mb_x && s->h263_pred){ //rare
 346                 C = mot_val[off[block] - wrap];
 347                 *px = mid_pred(A[0], 0, C[0]);
 348                 *py = mid_pred(A[1], 0, C[1]);
 349             }else{
 350                 *px = A[0];
 351                 *py = A[1];
 352             }
 353         }else{ /* block==2*/
 354             B = mot_val[ - wrap];
 355             C = mot_val[off[block] - wrap];
 356             if(s->mb_x == s->resync_mb_x) //rare
 357                 A[0]=A[1]=0;
 358
 359             *px = mid_pred(A[0], B[0], C[0]);
 360             *py = mid_pred(A[1], B[1], C[1]);
 361         }
 362     } else {
 363         B = mot_val[ - wrap];
 364         C = mot_val[off[block] - wrap];
 365         *px = mid_pred(A[0], B[0], C[0]);
 366         *py = mid_pred(A[1], B[1], C[1]);
 367     }
 368     return *mot_val;
 369 }
 370
 371
 372 /**
 373  * Get the GOB height based on picture height.
 374  */
 375 int ff_h263_get_gob_height(MpegEncContext *s){
 376     if (s->height <= 400)
 377         return 1;
 378     else if (s->height <= 800)
 379         return  2;
 380     else
 381         return 4;
 382 }