• Main Page
  • Related Pages
  • Modules
  • Data Structures
  • Files
  • File List
  • Globals

libavcodec/wmv2dec.c

Go to the documentation of this file.
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, s->avctx->extradata_size*8);
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 0
00120 {
00121 int i;
00122 for(i=0; i<s->gb.size*8; i++)
00123     printf("%d", get_bits1(&s->gb));
00124 //    get_bits1(&s->gb);
00125 printf("END\n");
00126 return -1;
00127 }
00128 #endif
00129     if(s->picture_number==0)
00130         decode_ext_header(w);
00131 
00132     s->pict_type = get_bits1(&s->gb) + 1;
00133     if(s->pict_type == FF_I_TYPE){
00134         code = get_bits(&s->gb, 7);
00135         av_log(s->avctx, AV_LOG_DEBUG, "I7:%X/\n", code);
00136     }
00137     s->chroma_qscale= s->qscale = get_bits(&s->gb, 5);
00138     if(s->qscale <= 0)
00139        return -1;
00140 
00141     return 0;
00142 }
00143 
00144 int ff_wmv2_decode_secondary_picture_header(MpegEncContext * s)
00145 {
00146     Wmv2Context * const w= (Wmv2Context*)s;
00147 
00148     if (s->pict_type == FF_I_TYPE) {
00149         if(w->j_type_bit) w->j_type= get_bits1(&s->gb);
00150         else              w->j_type= 0; //FIXME check
00151 
00152         if(!w->j_type){
00153             if(w->per_mb_rl_bit) s->per_mb_rl_table= get_bits1(&s->gb);
00154             else                 s->per_mb_rl_table= 0;
00155 
00156             if(!s->per_mb_rl_table){
00157                 s->rl_chroma_table_index = decode012(&s->gb);
00158                 s->rl_table_index = decode012(&s->gb);
00159             }
00160 
00161             s->dc_table_index = get_bits1(&s->gb);
00162         }
00163         s->inter_intra_pred= 0;
00164         s->no_rounding = 1;
00165         if(s->avctx->debug&FF_DEBUG_PICT_INFO){
00166             av_log(s->avctx, AV_LOG_DEBUG, "qscale:%d rlc:%d rl:%d dc:%d mbrl:%d j_type:%d \n",
00167                 s->qscale,
00168                 s->rl_chroma_table_index,
00169                 s->rl_table_index,
00170                 s->dc_table_index,
00171                 s->per_mb_rl_table,
00172                 w->j_type);
00173         }
00174     }else{
00175         int cbp_index;
00176         w->j_type=0;
00177 
00178         parse_mb_skip(w);
00179         cbp_index= decode012(&s->gb);
00180         if(s->qscale <= 10){
00181             int map[3]= {0,2,1};
00182             w->cbp_table_index= map[cbp_index];
00183         }else if(s->qscale <= 20){
00184             int map[3]= {1,0,2};
00185             w->cbp_table_index= map[cbp_index];
00186         }else{
00187             int map[3]= {2,1,0};
00188             w->cbp_table_index= map[cbp_index];
00189         }
00190 
00191         if(w->mspel_bit) s->mspel= get_bits1(&s->gb);
00192         else             s->mspel= 0; //FIXME check
00193 
00194         if(w->abt_flag){
00195             w->per_mb_abt= get_bits1(&s->gb)^1;
00196             if(!w->per_mb_abt){
00197                 w->abt_type= decode012(&s->gb);
00198             }
00199         }
00200 
00201         if(w->per_mb_rl_bit) s->per_mb_rl_table= get_bits1(&s->gb);
00202         else                 s->per_mb_rl_table= 0;
00203 
00204         if(!s->per_mb_rl_table){
00205             s->rl_table_index = decode012(&s->gb);
00206             s->rl_chroma_table_index = s->rl_table_index;
00207         }
00208 
00209         s->dc_table_index = get_bits1(&s->gb);
00210         s->mv_table_index = get_bits1(&s->gb);
00211 
00212         s->inter_intra_pred= 0;//(s->width*s->height < 320*240 && s->bit_rate<=II_BITRATE);
00213         s->no_rounding ^= 1;
00214 
00215         if(s->avctx->debug&FF_DEBUG_PICT_INFO){
00216             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",
00217                 s->rl_table_index,
00218                 s->rl_chroma_table_index,
00219                 s->dc_table_index,
00220                 s->mv_table_index,
00221                 s->per_mb_rl_table,
00222                 s->qscale,
00223                 s->mspel,
00224                 w->per_mb_abt,
00225                 w->abt_type,
00226                 w->cbp_table_index,
00227                 s->inter_intra_pred);
00228         }
00229     }
00230     s->esc3_level_length= 0;
00231     s->esc3_run_length= 0;
00232 
00233 s->picture_number++; //FIXME ?
00234 
00235 
00236     if(w->j_type){
00237         ff_intrax8_decode_picture(&w->x8, 2*s->qscale, (s->qscale-1)|1 );
00238         return 1;
00239     }
00240 
00241     return 0;
00242 }
00243 
00244 static inline int wmv2_decode_motion(Wmv2Context *w, int *mx_ptr, int *my_ptr){
00245     MpegEncContext * const s= &w->s;
00246     int ret;
00247 
00248     ret= ff_msmpeg4_decode_motion(s, mx_ptr, my_ptr);
00249 
00250     if(ret<0) return -1;
00251 
00252     if((((*mx_ptr)|(*my_ptr)) & 1) && s->mspel)
00253         w->hshift= get_bits1(&s->gb);
00254     else
00255         w->hshift= 0;
00256 
00257 //printf("%d %d  ", *mx_ptr, *my_ptr);
00258 
00259     return 0;
00260 }
00261 
00262 static int16_t *wmv2_pred_motion(Wmv2Context *w, int *px, int *py){
00263     MpegEncContext * const s= &w->s;
00264     int xy, wrap, diff, type;
00265     int16_t *A, *B, *C, *mot_val;
00266 
00267     wrap = s->b8_stride;
00268     xy = s->block_index[0];
00269 
00270     mot_val = s->current_picture.motion_val[0][xy];
00271 
00272     A = s->current_picture.motion_val[0][xy - 1];
00273     B = s->current_picture.motion_val[0][xy - wrap];
00274     C = s->current_picture.motion_val[0][xy + 2 - wrap];
00275 
00276     if(s->mb_x && !s->first_slice_line && !s->mspel && w->top_left_mv_flag)
00277         diff= FFMAX(FFABS(A[0] - B[0]), FFABS(A[1] - B[1]));
00278     else
00279         diff=0;
00280 
00281     if(diff >= 8)
00282         type= get_bits1(&s->gb);
00283     else
00284         type= 2;
00285 
00286     if(type == 0){
00287         *px= A[0];
00288         *py= A[1];
00289     }else if(type == 1){
00290         *px= B[0];
00291         *py= B[1];
00292     }else{
00293         /* special case for first (slice) line */
00294         if (s->first_slice_line) {
00295             *px = A[0];
00296             *py = A[1];
00297         } else {
00298             *px = mid_pred(A[0], B[0], C[0]);
00299             *py = mid_pred(A[1], B[1], C[1]);
00300         }
00301     }
00302 
00303     return mot_val;
00304 }
00305 
00306 static inline int wmv2_decode_inter_block(Wmv2Context *w, DCTELEM *block, int n, int cbp){
00307     MpegEncContext * const s= &w->s;
00308     static const int sub_cbp_table[3]= {2,3,1};
00309     int sub_cbp;
00310 
00311     if(!cbp){
00312         s->block_last_index[n] = -1;
00313 
00314         return 0;
00315     }
00316 
00317     if(w->per_block_abt)
00318         w->abt_type= decode012(&s->gb);
00319 #if 0
00320     if(w->per_block_abt)
00321         printf("B%d", w->abt_type);
00322 #endif
00323     w->abt_type_table[n]= w->abt_type;
00324 
00325     if(w->abt_type){
00326 //        const uint8_t *scantable= w->abt_scantable[w->abt_type-1].permutated;
00327         const uint8_t *scantable= w->abt_scantable[w->abt_type-1].scantable;
00328 //        const uint8_t *scantable= w->abt_type-1 ? w->abt_scantable[1].permutated : w->abt_scantable[0].scantable;
00329 
00330         sub_cbp= sub_cbp_table[ decode012(&s->gb) ];
00331 //        printf("S%d", sub_cbp);
00332 
00333         if(sub_cbp&1){
00334             if (ff_msmpeg4_decode_block(s, block, n, 1, scantable) < 0)
00335                 return -1;
00336         }
00337 
00338         if(sub_cbp&2){
00339             if (ff_msmpeg4_decode_block(s, w->abt_block2[n], n, 1, scantable) < 0)
00340                 return -1;
00341         }
00342         s->block_last_index[n] = 63;
00343 
00344         return 0;
00345     }else{
00346         return ff_msmpeg4_decode_block(s, block, n, 1, s->inter_scantable.permutated);
00347     }
00348 }
00349 
00350 
00351 int ff_wmv2_decode_mb(MpegEncContext *s, DCTELEM block[6][64])
00352 {
00353     Wmv2Context * const w= (Wmv2Context*)s;
00354     int cbp, code, i;
00355     uint8_t *coded_val;
00356 
00357     if(w->j_type) return 0;
00358 
00359     if (s->pict_type == FF_P_TYPE) {
00360         if(IS_SKIP(s->current_picture.mb_type[s->mb_y * s->mb_stride + s->mb_x])){
00361             /* skip mb */
00362             s->mb_intra = 0;
00363             for(i=0;i<6;i++)
00364                 s->block_last_index[i] = -1;
00365             s->mv_dir = MV_DIR_FORWARD;
00366             s->mv_type = MV_TYPE_16X16;
00367             s->mv[0][0][0] = 0;
00368             s->mv[0][0][1] = 0;
00369             s->mb_skipped = 1;
00370             w->hshift=0;
00371             return 0;
00372         }
00373 
00374         code = get_vlc2(&s->gb, ff_mb_non_intra_vlc[w->cbp_table_index].table, MB_NON_INTRA_VLC_BITS, 3);
00375         if (code < 0)
00376             return -1;
00377         s->mb_intra = (~code & 0x40) >> 6;
00378 
00379         cbp = code & 0x3f;
00380     } else {
00381         s->mb_intra = 1;
00382         code = get_vlc2(&s->gb, ff_msmp4_mb_i_vlc.table, MB_INTRA_VLC_BITS, 2);
00383         if (code < 0){
00384             av_log(s->avctx, AV_LOG_ERROR, "II-cbp illegal at %d %d\n", s->mb_x, s->mb_y);
00385             return -1;
00386         }
00387         /* predict coded block pattern */
00388         cbp = 0;
00389         for(i=0;i<6;i++) {
00390             int val = ((code >> (5 - i)) & 1);
00391             if (i < 4) {
00392                 int pred = ff_msmpeg4_coded_block_pred(s, i, &coded_val);
00393                 val = val ^ pred;
00394                 *coded_val = val;
00395             }
00396             cbp |= val << (5 - i);
00397         }
00398     }
00399 
00400     if (!s->mb_intra) {
00401         int mx, my;
00402 //printf("P at %d %d\n", s->mb_x, s->mb_y);
00403         wmv2_pred_motion(w, &mx, &my);
00404 
00405         if(cbp){
00406             s->dsp.clear_blocks(s->block[0]);
00407             if(s->per_mb_rl_table){
00408                 s->rl_table_index = decode012(&s->gb);
00409                 s->rl_chroma_table_index = s->rl_table_index;
00410             }
00411 
00412             if(w->abt_flag && w->per_mb_abt){
00413                 w->per_block_abt= get_bits1(&s->gb);
00414                 if(!w->per_block_abt)
00415                     w->abt_type= decode012(&s->gb);
00416             }else
00417                 w->per_block_abt=0;
00418         }
00419 
00420         if (wmv2_decode_motion(w, &mx, &my) < 0)
00421             return -1;
00422 
00423         s->mv_dir = MV_DIR_FORWARD;
00424         s->mv_type = MV_TYPE_16X16;
00425         s->mv[0][0][0] = mx;
00426         s->mv[0][0][1] = my;
00427 
00428         for (i = 0; i < 6; i++) {
00429             if (wmv2_decode_inter_block(w, block[i], i, (cbp >> (5 - i)) & 1) < 0)
00430             {
00431                 av_log(s->avctx, AV_LOG_ERROR, "\nerror while decoding inter block: %d x %d (%d)\n", s->mb_x, s->mb_y, i);
00432                 return -1;
00433             }
00434         }
00435     } else {
00436 //if(s->pict_type==FF_P_TYPE)
00437 //   printf("%d%d ", s->inter_intra_pred, cbp);
00438 //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));
00439         s->ac_pred = get_bits1(&s->gb);
00440         if(s->inter_intra_pred){
00441             s->h263_aic_dir= get_vlc2(&s->gb, ff_inter_intra_vlc.table, INTER_INTRA_VLC_BITS, 1);
00442 //            printf("%d%d %d %d/", s->ac_pred, s->h263_aic_dir, s->mb_x, s->mb_y);
00443         }
00444         if(s->per_mb_rl_table && cbp){
00445             s->rl_table_index = decode012(&s->gb);
00446             s->rl_chroma_table_index = s->rl_table_index;
00447         }
00448 
00449         s->dsp.clear_blocks(s->block[0]);
00450         for (i = 0; i < 6; i++) {
00451             if (ff_msmpeg4_decode_block(s, block[i], i, (cbp >> (5 - i)) & 1, NULL) < 0)
00452             {
00453                 av_log(s->avctx, AV_LOG_ERROR, "\nerror while decoding intra block: %d x %d (%d)\n", s->mb_x, s->mb_y, i);
00454                 return -1;
00455             }
00456         }
00457     }
00458 
00459     return 0;
00460 }
00461 
00462 static av_cold int wmv2_decode_init(AVCodecContext *avctx){
00463     Wmv2Context * const w= avctx->priv_data;
00464 
00465     if(avctx->idct_algo==FF_IDCT_AUTO){
00466         avctx->idct_algo=FF_IDCT_WMV2;
00467     }
00468 
00469     if(ff_msmpeg4_decode_init(avctx) < 0)
00470         return -1;
00471 
00472     ff_wmv2_common_init(w);
00473 
00474     ff_intrax8_common_init(&w->x8,&w->s);
00475 
00476     return 0;
00477 }
00478 
00479 static av_cold int wmv2_decode_end(AVCodecContext *avctx)
00480 {
00481     Wmv2Context *w = avctx->priv_data;
00482 
00483     ff_intrax8_common_end(&w->x8);
00484     return ff_h263_decode_end(avctx);
00485 }
00486 
00487 AVCodec wmv2_decoder = {
00488     "wmv2",
00489     AVMEDIA_TYPE_VIDEO,
00490     CODEC_ID_WMV2,
00491     sizeof(Wmv2Context),
00492     wmv2_decode_init,
00493     NULL,
00494     wmv2_decode_end,
00495     ff_h263_decode_frame,
00496     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
00497     .long_name = NULL_IF_CONFIG_SMALL("Windows Media Video 8"),
00498     .pix_fmts= ff_pixfmt_list_420,
00499 };

Generated on Fri Sep 16 2011 17:17:46 for FFmpeg by  doxygen 1.7.1