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libavcodec/wmv2dec.c

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00001 /*
00002  * Copyright (c) 2002 The FFmpeg Project
00003  *
00004  * This file is part of FFmpeg.
00005  *
00006  * FFmpeg is free software; you can redistribute it and/or
00007  * modify it under the terms of the GNU Lesser General Public
00008  * License as published by the Free Software Foundation; either
00009  * version 2.1 of the License, or (at your option) any later version.
00010  *
00011  * FFmpeg is distributed in the hope that it will be useful,
00012  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00013  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00014  * Lesser General Public License for more details.
00015  *
00016  * You should have received a copy of the GNU Lesser General Public
00017  * License along with FFmpeg; if not, write to the Free Software
00018  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00019  */
00020 
00021 #include "avcodec.h"
00022 #include "dsputil.h"
00023 #include "mpegvideo.h"
00024 #include "h263.h"
00025 #include "mathops.h"
00026 #include "msmpeg4.h"
00027 #include "msmpeg4data.h"
00028 #include "intrax8.h"
00029 #include "wmv2.h"
00030 
00031 
00032 static void parse_mb_skip(Wmv2Context * w){
00033     int mb_x, mb_y;
00034     MpegEncContext * const s= &w->s;
00035     uint32_t * const mb_type= s->current_picture_ptr->mb_type;
00036 
00037     w->skip_type= get_bits(&s->gb, 2);
00038     switch(w->skip_type){
00039     case SKIP_TYPE_NONE:
00040         for(mb_y=0; mb_y<s->mb_height; mb_y++){
00041             for(mb_x=0; mb_x<s->mb_width; mb_x++){
00042                 mb_type[mb_y*s->mb_stride + mb_x]= MB_TYPE_16x16 | MB_TYPE_L0;
00043             }
00044         }
00045         break;
00046     case SKIP_TYPE_MPEG:
00047         for(mb_y=0; mb_y<s->mb_height; mb_y++){
00048             for(mb_x=0; mb_x<s->mb_width; mb_x++){
00049                 mb_type[mb_y*s->mb_stride + mb_x]= (get_bits1(&s->gb) ? MB_TYPE_SKIP : 0) | MB_TYPE_16x16 | MB_TYPE_L0;
00050             }
00051         }
00052         break;
00053     case SKIP_TYPE_ROW:
00054         for(mb_y=0; mb_y<s->mb_height; mb_y++){
00055             if(get_bits1(&s->gb)){
00056                 for(mb_x=0; mb_x<s->mb_width; mb_x++){
00057                     mb_type[mb_y*s->mb_stride + mb_x]=  MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_L0;
00058                 }
00059             }else{
00060                 for(mb_x=0; mb_x<s->mb_width; mb_x++){
00061                     mb_type[mb_y*s->mb_stride + mb_x]= (get_bits1(&s->gb) ? MB_TYPE_SKIP : 0) | MB_TYPE_16x16 | MB_TYPE_L0;
00062                 }
00063             }
00064         }
00065         break;
00066     case SKIP_TYPE_COL:
00067         for(mb_x=0; mb_x<s->mb_width; mb_x++){
00068             if(get_bits1(&s->gb)){
00069                 for(mb_y=0; mb_y<s->mb_height; mb_y++){
00070                     mb_type[mb_y*s->mb_stride + mb_x]=  MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_L0;
00071                 }
00072             }else{
00073                 for(mb_y=0; mb_y<s->mb_height; mb_y++){
00074                     mb_type[mb_y*s->mb_stride + mb_x]= (get_bits1(&s->gb) ? MB_TYPE_SKIP : 0) | MB_TYPE_16x16 | MB_TYPE_L0;
00075                 }
00076             }
00077         }
00078         break;
00079     }
00080 }
00081 
00082 static int decode_ext_header(Wmv2Context *w){
00083     MpegEncContext * const s= &w->s;
00084     GetBitContext gb;
00085     int fps;
00086     int code;
00087 
00088     if(s->avctx->extradata_size<4) return -1;
00089 
00090     init_get_bits(&gb, s->avctx->extradata, 32);
00091 
00092     fps                = get_bits(&gb, 5);
00093     s->bit_rate        = get_bits(&gb, 11)*1024;
00094     w->mspel_bit       = get_bits1(&gb);
00095     s->loop_filter     = get_bits1(&gb);
00096     w->abt_flag        = get_bits1(&gb);
00097     w->j_type_bit      = get_bits1(&gb);
00098     w->top_left_mv_flag= get_bits1(&gb);
00099     w->per_mb_rl_bit   = get_bits1(&gb);
00100     code               = get_bits(&gb, 3);
00101 
00102     if(code==0) return -1;
00103 
00104     s->slice_height = s->mb_height / code;
00105 
00106     if(s->avctx->debug&FF_DEBUG_PICT_INFO){
00107         av_log(s->avctx, AV_LOG_DEBUG, "fps:%d, br:%d, qpbit:%d, abt_flag:%d, j_type_bit:%d, tl_mv_flag:%d, mbrl_bit:%d, code:%d, loop_filter:%d, slices:%d\n",
00108         fps, s->bit_rate, w->mspel_bit, w->abt_flag, w->j_type_bit, w->top_left_mv_flag, w->per_mb_rl_bit, code, s->loop_filter,
00109         code);
00110     }
00111     return 0;
00112 }
00113 
00114 int ff_wmv2_decode_picture_header(MpegEncContext * s)
00115 {
00116     Wmv2Context * const w= (Wmv2Context*)s;
00117     int code;
00118 
00119     if(s->picture_number==0)
00120         decode_ext_header(w);
00121 
00122     s->pict_type = get_bits1(&s->gb) + 1;
00123     if(s->pict_type == AV_PICTURE_TYPE_I){
00124         code = get_bits(&s->gb, 7);
00125         av_log(s->avctx, AV_LOG_DEBUG, "I7:%X/\n", code);
00126     }
00127     s->chroma_qscale= s->qscale = get_bits(&s->gb, 5);
00128     if(s->qscale <= 0)
00129        return -1;
00130 
00131     return 0;
00132 }
00133 
00134 int ff_wmv2_decode_secondary_picture_header(MpegEncContext * s)
00135 {
00136     Wmv2Context * const w= (Wmv2Context*)s;
00137 
00138     if (s->pict_type == AV_PICTURE_TYPE_I) {
00139         if(w->j_type_bit) w->j_type= get_bits1(&s->gb);
00140         else              w->j_type= 0; //FIXME check
00141 
00142         if(!w->j_type){
00143             if(w->per_mb_rl_bit) s->per_mb_rl_table= get_bits1(&s->gb);
00144             else                 s->per_mb_rl_table= 0;
00145 
00146             if(!s->per_mb_rl_table){
00147                 s->rl_chroma_table_index = decode012(&s->gb);
00148                 s->rl_table_index = decode012(&s->gb);
00149             }
00150 
00151             s->dc_table_index = get_bits1(&s->gb);
00152         }
00153         s->inter_intra_pred= 0;
00154         s->no_rounding = 1;
00155         if(s->avctx->debug&FF_DEBUG_PICT_INFO){
00156             av_log(s->avctx, AV_LOG_DEBUG, "qscale:%d rlc:%d rl:%d dc:%d mbrl:%d j_type:%d \n",
00157                 s->qscale,
00158                 s->rl_chroma_table_index,
00159                 s->rl_table_index,
00160                 s->dc_table_index,
00161                 s->per_mb_rl_table,
00162                 w->j_type);
00163         }
00164     }else{
00165         int cbp_index;
00166         w->j_type=0;
00167 
00168         parse_mb_skip(w);
00169         cbp_index= decode012(&s->gb);
00170         if(s->qscale <= 10){
00171             int map[3]= {0,2,1};
00172             w->cbp_table_index= map[cbp_index];
00173         }else if(s->qscale <= 20){
00174             int map[3]= {1,0,2};
00175             w->cbp_table_index= map[cbp_index];
00176         }else{
00177             int map[3]= {2,1,0};
00178             w->cbp_table_index= map[cbp_index];
00179         }
00180 
00181         if(w->mspel_bit) s->mspel= get_bits1(&s->gb);
00182         else             s->mspel= 0; //FIXME check
00183 
00184         if(w->abt_flag){
00185             w->per_mb_abt= get_bits1(&s->gb)^1;
00186             if(!w->per_mb_abt){
00187                 w->abt_type= decode012(&s->gb);
00188             }
00189         }
00190 
00191         if(w->per_mb_rl_bit) s->per_mb_rl_table= get_bits1(&s->gb);
00192         else                 s->per_mb_rl_table= 0;
00193 
00194         if(!s->per_mb_rl_table){
00195             s->rl_table_index = decode012(&s->gb);
00196             s->rl_chroma_table_index = s->rl_table_index;
00197         }
00198 
00199         s->dc_table_index = get_bits1(&s->gb);
00200         s->mv_table_index = get_bits1(&s->gb);
00201 
00202         s->inter_intra_pred= 0;//(s->width*s->height < 320*240 && s->bit_rate<=II_BITRATE);
00203         s->no_rounding ^= 1;
00204 
00205         if(s->avctx->debug&FF_DEBUG_PICT_INFO){
00206             av_log(s->avctx, AV_LOG_DEBUG, "rl:%d rlc:%d dc:%d mv:%d mbrl:%d qp:%d mspel:%d per_mb_abt:%d abt_type:%d cbp:%d ii:%d\n",
00207                 s->rl_table_index,
00208                 s->rl_chroma_table_index,
00209                 s->dc_table_index,
00210                 s->mv_table_index,
00211                 s->per_mb_rl_table,
00212                 s->qscale,
00213                 s->mspel,
00214                 w->per_mb_abt,
00215                 w->abt_type,
00216                 w->cbp_table_index,
00217                 s->inter_intra_pred);
00218         }
00219     }
00220     s->esc3_level_length= 0;
00221     s->esc3_run_length= 0;
00222 
00223 s->picture_number++; //FIXME ?
00224 
00225 
00226     if(w->j_type){
00227         ff_intrax8_decode_picture(&w->x8, 2*s->qscale, (s->qscale-1)|1 );
00228         return 1;
00229     }
00230 
00231     return 0;
00232 }
00233 
00234 static inline int wmv2_decode_motion(Wmv2Context *w, int *mx_ptr, int *my_ptr){
00235     MpegEncContext * const s= &w->s;
00236     int ret;
00237 
00238     ret= ff_msmpeg4_decode_motion(s, mx_ptr, my_ptr);
00239 
00240     if(ret<0) return -1;
00241 
00242     if((((*mx_ptr)|(*my_ptr)) & 1) && s->mspel)
00243         w->hshift= get_bits1(&s->gb);
00244     else
00245         w->hshift= 0;
00246 
00247 //printf("%d %d  ", *mx_ptr, *my_ptr);
00248 
00249     return 0;
00250 }
00251 
00252 static int16_t *wmv2_pred_motion(Wmv2Context *w, int *px, int *py){
00253     MpegEncContext * const s= &w->s;
00254     int xy, wrap, diff, type;
00255     int16_t *A, *B, *C, *mot_val;
00256 
00257     wrap = s->b8_stride;
00258     xy = s->block_index[0];
00259 
00260     mot_val = s->current_picture.motion_val[0][xy];
00261 
00262     A = s->current_picture.motion_val[0][xy - 1];
00263     B = s->current_picture.motion_val[0][xy - wrap];
00264     C = s->current_picture.motion_val[0][xy + 2 - wrap];
00265 
00266     if(s->mb_x && !s->first_slice_line && !s->mspel && w->top_left_mv_flag)
00267         diff= FFMAX(FFABS(A[0] - B[0]), FFABS(A[1] - B[1]));
00268     else
00269         diff=0;
00270 
00271     if(diff >= 8)
00272         type= get_bits1(&s->gb);
00273     else
00274         type= 2;
00275 
00276     if(type == 0){
00277         *px= A[0];
00278         *py= A[1];
00279     }else if(type == 1){
00280         *px= B[0];
00281         *py= B[1];
00282     }else{
00283         /* special case for first (slice) line */
00284         if (s->first_slice_line) {
00285             *px = A[0];
00286             *py = A[1];
00287         } else {
00288             *px = mid_pred(A[0], B[0], C[0]);
00289             *py = mid_pred(A[1], B[1], C[1]);
00290         }
00291     }
00292 
00293     return mot_val;
00294 }
00295 
00296 static inline int wmv2_decode_inter_block(Wmv2Context *w, DCTELEM *block, int n, int cbp){
00297     MpegEncContext * const s= &w->s;
00298     static const int sub_cbp_table[3]= {2,3,1};
00299     int sub_cbp;
00300 
00301     if(!cbp){
00302         s->block_last_index[n] = -1;
00303 
00304         return 0;
00305     }
00306 
00307     if(w->per_block_abt)
00308         w->abt_type= decode012(&s->gb);
00309     w->abt_type_table[n]= w->abt_type;
00310 
00311     if(w->abt_type){
00312 //        const uint8_t *scantable= w->abt_scantable[w->abt_type-1].permutated;
00313         const uint8_t *scantable= w->abt_scantable[w->abt_type-1].scantable;
00314 //        const uint8_t *scantable= w->abt_type-1 ? w->abt_scantable[1].permutated : w->abt_scantable[0].scantable;
00315 
00316         sub_cbp= sub_cbp_table[ decode012(&s->gb) ];
00317 //        printf("S%d", sub_cbp);
00318 
00319         if(sub_cbp&1){
00320             if (ff_msmpeg4_decode_block(s, block, n, 1, scantable) < 0)
00321                 return -1;
00322         }
00323 
00324         if(sub_cbp&2){
00325             if (ff_msmpeg4_decode_block(s, w->abt_block2[n], n, 1, scantable) < 0)
00326                 return -1;
00327         }
00328         s->block_last_index[n] = 63;
00329 
00330         return 0;
00331     }else{
00332         return ff_msmpeg4_decode_block(s, block, n, 1, s->inter_scantable.permutated);
00333     }
00334 }
00335 
00336 
00337 int ff_wmv2_decode_mb(MpegEncContext *s, DCTELEM block[6][64])
00338 {
00339     Wmv2Context * const w= (Wmv2Context*)s;
00340     int cbp, code, i;
00341     uint8_t *coded_val;
00342 
00343     if(w->j_type) return 0;
00344 
00345     if (s->pict_type == AV_PICTURE_TYPE_P) {
00346         if(IS_SKIP(s->current_picture.mb_type[s->mb_y * s->mb_stride + s->mb_x])){
00347             /* skip mb */
00348             s->mb_intra = 0;
00349             for(i=0;i<6;i++)
00350                 s->block_last_index[i] = -1;
00351             s->mv_dir = MV_DIR_FORWARD;
00352             s->mv_type = MV_TYPE_16X16;
00353             s->mv[0][0][0] = 0;
00354             s->mv[0][0][1] = 0;
00355             s->mb_skipped = 1;
00356             w->hshift=0;
00357             return 0;
00358         }
00359 
00360         code = get_vlc2(&s->gb, ff_mb_non_intra_vlc[w->cbp_table_index].table, MB_NON_INTRA_VLC_BITS, 3);
00361         if (code < 0)
00362             return -1;
00363         s->mb_intra = (~code & 0x40) >> 6;
00364 
00365         cbp = code & 0x3f;
00366     } else {
00367         s->mb_intra = 1;
00368         code = get_vlc2(&s->gb, ff_msmp4_mb_i_vlc.table, MB_INTRA_VLC_BITS, 2);
00369         if (code < 0){
00370             av_log(s->avctx, AV_LOG_ERROR, "II-cbp illegal at %d %d\n", s->mb_x, s->mb_y);
00371             return -1;
00372         }
00373         /* predict coded block pattern */
00374         cbp = 0;
00375         for(i=0;i<6;i++) {
00376             int val = ((code >> (5 - i)) & 1);
00377             if (i < 4) {
00378                 int pred = ff_msmpeg4_coded_block_pred(s, i, &coded_val);
00379                 val = val ^ pred;
00380                 *coded_val = val;
00381             }
00382             cbp |= val << (5 - i);
00383         }
00384     }
00385 
00386     if (!s->mb_intra) {
00387         int mx, my;
00388 //printf("P at %d %d\n", s->mb_x, s->mb_y);
00389         wmv2_pred_motion(w, &mx, &my);
00390 
00391         if(cbp){
00392             s->dsp.clear_blocks(s->block[0]);
00393             if(s->per_mb_rl_table){
00394                 s->rl_table_index = decode012(&s->gb);
00395                 s->rl_chroma_table_index = s->rl_table_index;
00396             }
00397 
00398             if(w->abt_flag && w->per_mb_abt){
00399                 w->per_block_abt= get_bits1(&s->gb);
00400                 if(!w->per_block_abt)
00401                     w->abt_type= decode012(&s->gb);
00402             }else
00403                 w->per_block_abt=0;
00404         }
00405 
00406         if (wmv2_decode_motion(w, &mx, &my) < 0)
00407             return -1;
00408 
00409         s->mv_dir = MV_DIR_FORWARD;
00410         s->mv_type = MV_TYPE_16X16;
00411         s->mv[0][0][0] = mx;
00412         s->mv[0][0][1] = my;
00413 
00414         for (i = 0; i < 6; i++) {
00415             if (wmv2_decode_inter_block(w, block[i], i, (cbp >> (5 - i)) & 1) < 0)
00416             {
00417                 av_log(s->avctx, AV_LOG_ERROR, "\nerror while decoding inter block: %d x %d (%d)\n", s->mb_x, s->mb_y, i);
00418                 return -1;
00419             }
00420         }
00421     } else {
00422 //if(s->pict_type==AV_PICTURE_TYPE_P)
00423 //   printf("%d%d ", s->inter_intra_pred, cbp);
00424 //printf("I at %d %d %d %06X\n", s->mb_x, s->mb_y, ((cbp&3)? 1 : 0) +((cbp&0x3C)? 2 : 0), show_bits(&s->gb, 24));
00425         s->ac_pred = get_bits1(&s->gb);
00426         if(s->inter_intra_pred){
00427             s->h263_aic_dir= get_vlc2(&s->gb, ff_inter_intra_vlc.table, INTER_INTRA_VLC_BITS, 1);
00428 //            printf("%d%d %d %d/", s->ac_pred, s->h263_aic_dir, s->mb_x, s->mb_y);
00429         }
00430         if(s->per_mb_rl_table && cbp){
00431             s->rl_table_index = decode012(&s->gb);
00432             s->rl_chroma_table_index = s->rl_table_index;
00433         }
00434 
00435         s->dsp.clear_blocks(s->block[0]);
00436         for (i = 0; i < 6; i++) {
00437             if (ff_msmpeg4_decode_block(s, block[i], i, (cbp >> (5 - i)) & 1, NULL) < 0)
00438             {
00439                 av_log(s->avctx, AV_LOG_ERROR, "\nerror while decoding intra block: %d x %d (%d)\n", s->mb_x, s->mb_y, i);
00440                 return -1;
00441             }
00442         }
00443     }
00444 
00445     return 0;
00446 }
00447 
00448 static av_cold int wmv2_decode_init(AVCodecContext *avctx){
00449     Wmv2Context * const w= avctx->priv_data;
00450 
00451     if(avctx->idct_algo==FF_IDCT_AUTO){
00452         avctx->idct_algo=FF_IDCT_WMV2;
00453     }
00454 
00455     if(ff_msmpeg4_decode_init(avctx) < 0)
00456         return -1;
00457 
00458     ff_wmv2_common_init(w);
00459 
00460     ff_intrax8_common_init(&w->x8,&w->s);
00461 
00462     return 0;
00463 }
00464 
00465 static av_cold int wmv2_decode_end(AVCodecContext *avctx)
00466 {
00467     Wmv2Context *w = avctx->priv_data;
00468 
00469     ff_intrax8_common_end(&w->x8);
00470     return ff_h263_decode_end(avctx);
00471 }
00472 
00473 AVCodec ff_wmv2_decoder = {
00474     "wmv2",
00475     AVMEDIA_TYPE_VIDEO,
00476     CODEC_ID_WMV2,
00477     sizeof(Wmv2Context),
00478     wmv2_decode_init,
00479     NULL,
00480     wmv2_decode_end,
00481     ff_h263_decode_frame,
00482     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
00483     .long_name = NULL_IF_CONFIG_SMALL("Windows Media Video 8"),
00484     .pix_fmts= ff_pixfmt_list_420,
00485 };

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