Libav
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00001 /* 00002 * ITU H263 bitstream decoder 00003 * Copyright (c) 2000,2001 Fabrice Bellard 00004 * H263+ support. 00005 * Copyright (c) 2001 Juan J. Sierralta P 00006 * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at> 00007 * 00008 * This file is part of FFmpeg. 00009 * 00010 * FFmpeg is free software; you can redistribute it and/or 00011 * modify it under the terms of the GNU Lesser General Public 00012 * License as published by the Free Software Foundation; either 00013 * version 2.1 of the License, or (at your option) any later version. 00014 * 00015 * FFmpeg is distributed in the hope that it will be useful, 00016 * but WITHOUT ANY WARRANTY; without even the implied warranty of 00017 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 00018 * Lesser General Public License for more details. 00019 * 00020 * You should have received a copy of the GNU Lesser General Public 00021 * License along with FFmpeg; if not, write to the Free Software 00022 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 00023 */ 00024 00030 //#define DEBUG 00031 #include <limits.h> 00032 00033 #include "dsputil.h" 00034 #include "avcodec.h" 00035 #include "mpegvideo.h" 00036 #include "h263.h" 00037 #include "mathops.h" 00038 #include "unary.h" 00039 #include "flv.h" 00040 #include "mpeg4video.h" 00041 00042 //#undef NDEBUG 00043 //#include <assert.h> 00044 00045 // The defines below define the number of bits that are read at once for 00046 // reading vlc values. Changing these may improve speed and data cache needs 00047 // be aware though that decreasing them may need the number of stages that is 00048 // passed to get_vlc* to be increased. 00049 #define MV_VLC_BITS 9 00050 #define H263_MBTYPE_B_VLC_BITS 6 00051 #define CBPC_B_VLC_BITS 3 00052 00053 static const int h263_mb_type_b_map[15]= { 00054 MB_TYPE_DIRECT2 | MB_TYPE_L0L1, 00055 MB_TYPE_DIRECT2 | MB_TYPE_L0L1 | MB_TYPE_CBP, 00056 MB_TYPE_DIRECT2 | MB_TYPE_L0L1 | MB_TYPE_CBP | MB_TYPE_QUANT, 00057 MB_TYPE_L0 | MB_TYPE_16x16, 00058 MB_TYPE_L0 | MB_TYPE_CBP | MB_TYPE_16x16, 00059 MB_TYPE_L0 | MB_TYPE_CBP | MB_TYPE_QUANT | MB_TYPE_16x16, 00060 MB_TYPE_L1 | MB_TYPE_16x16, 00061 MB_TYPE_L1 | MB_TYPE_CBP | MB_TYPE_16x16, 00062 MB_TYPE_L1 | MB_TYPE_CBP | MB_TYPE_QUANT | MB_TYPE_16x16, 00063 MB_TYPE_L0L1 | MB_TYPE_16x16, 00064 MB_TYPE_L0L1 | MB_TYPE_CBP | MB_TYPE_16x16, 00065 MB_TYPE_L0L1 | MB_TYPE_CBP | MB_TYPE_QUANT | MB_TYPE_16x16, 00066 0, //stuffing 00067 MB_TYPE_INTRA4x4 | MB_TYPE_CBP, 00068 MB_TYPE_INTRA4x4 | MB_TYPE_CBP | MB_TYPE_QUANT, 00069 }; 00070 00071 void ff_h263_show_pict_info(MpegEncContext *s){ 00072 if(s->avctx->debug&FF_DEBUG_PICT_INFO){ 00073 av_log(s->avctx, AV_LOG_DEBUG, "qp:%d %c size:%d rnd:%d%s%s%s%s%s%s%s%s%s %d/%d\n", 00074 s->qscale, av_get_pict_type_char(s->pict_type), 00075 s->gb.size_in_bits, 1-s->no_rounding, 00076 s->obmc ? " AP" : "", 00077 s->umvplus ? " UMV" : "", 00078 s->h263_long_vectors ? " LONG" : "", 00079 s->h263_plus ? " +" : "", 00080 s->h263_aic ? " AIC" : "", 00081 s->alt_inter_vlc ? " AIV" : "", 00082 s->modified_quant ? " MQ" : "", 00083 s->loop_filter ? " LOOP" : "", 00084 s->h263_slice_structured ? " SS" : "", 00085 s->avctx->time_base.den, s->avctx->time_base.num 00086 ); 00087 } 00088 } 00089 00090 /***********************************************/ 00091 /* decoding */ 00092 00093 VLC ff_h263_intra_MCBPC_vlc; 00094 VLC ff_h263_inter_MCBPC_vlc; 00095 VLC ff_h263_cbpy_vlc; 00096 static VLC mv_vlc; 00097 static VLC h263_mbtype_b_vlc; 00098 static VLC cbpc_b_vlc; 00099 00100 /* init vlcs */ 00101 00102 /* XXX: find a better solution to handle static init */ 00103 void h263_decode_init_vlc(MpegEncContext *s) 00104 { 00105 static int done = 0; 00106 00107 if (!done) { 00108 done = 1; 00109 00110 INIT_VLC_STATIC(&ff_h263_intra_MCBPC_vlc, INTRA_MCBPC_VLC_BITS, 9, 00111 ff_h263_intra_MCBPC_bits, 1, 1, 00112 ff_h263_intra_MCBPC_code, 1, 1, 72); 00113 INIT_VLC_STATIC(&ff_h263_inter_MCBPC_vlc, INTER_MCBPC_VLC_BITS, 28, 00114 ff_h263_inter_MCBPC_bits, 1, 1, 00115 ff_h263_inter_MCBPC_code, 1, 1, 198); 00116 INIT_VLC_STATIC(&ff_h263_cbpy_vlc, CBPY_VLC_BITS, 16, 00117 &ff_h263_cbpy_tab[0][1], 2, 1, 00118 &ff_h263_cbpy_tab[0][0], 2, 1, 64); 00119 INIT_VLC_STATIC(&mv_vlc, MV_VLC_BITS, 33, 00120 &mvtab[0][1], 2, 1, 00121 &mvtab[0][0], 2, 1, 538); 00122 init_rl(&ff_h263_rl_inter, ff_h263_static_rl_table_store[0]); 00123 init_rl(&rl_intra_aic, ff_h263_static_rl_table_store[1]); 00124 INIT_VLC_RL(ff_h263_rl_inter, 554); 00125 INIT_VLC_RL(rl_intra_aic, 554); 00126 INIT_VLC_STATIC(&h263_mbtype_b_vlc, H263_MBTYPE_B_VLC_BITS, 15, 00127 &h263_mbtype_b_tab[0][1], 2, 1, 00128 &h263_mbtype_b_tab[0][0], 2, 1, 80); 00129 INIT_VLC_STATIC(&cbpc_b_vlc, CBPC_B_VLC_BITS, 4, 00130 &cbpc_b_tab[0][1], 2, 1, 00131 &cbpc_b_tab[0][0], 2, 1, 8); 00132 } 00133 } 00134 00135 int ff_h263_decode_mba(MpegEncContext *s) 00136 { 00137 int i, mb_pos; 00138 00139 for(i=0; i<6; i++){ 00140 if(s->mb_num-1 <= ff_mba_max[i]) break; 00141 } 00142 mb_pos= get_bits(&s->gb, ff_mba_length[i]); 00143 s->mb_x= mb_pos % s->mb_width; 00144 s->mb_y= mb_pos / s->mb_width; 00145 00146 return mb_pos; 00147 } 00148 00153 static int h263_decode_gob_header(MpegEncContext *s) 00154 { 00155 unsigned int val, gfid, gob_number; 00156 int left; 00157 00158 /* Check for GOB Start Code */ 00159 val = show_bits(&s->gb, 16); 00160 if(val) 00161 return -1; 00162 00163 /* We have a GBSC probably with GSTUFF */ 00164 skip_bits(&s->gb, 16); /* Drop the zeros */ 00165 left= get_bits_left(&s->gb); 00166 //MN: we must check the bits left or we might end in a infinite loop (or segfault) 00167 for(;left>13; left--){ 00168 if(get_bits1(&s->gb)) break; /* Seek the '1' bit */ 00169 } 00170 if(left<=13) 00171 return -1; 00172 00173 if(s->h263_slice_structured){ 00174 if(get_bits1(&s->gb)==0) 00175 return -1; 00176 00177 ff_h263_decode_mba(s); 00178 00179 if(s->mb_num > 1583) 00180 if(get_bits1(&s->gb)==0) 00181 return -1; 00182 00183 s->qscale = get_bits(&s->gb, 5); /* SQUANT */ 00184 if(get_bits1(&s->gb)==0) 00185 return -1; 00186 gfid = get_bits(&s->gb, 2); /* GFID */ 00187 }else{ 00188 gob_number = get_bits(&s->gb, 5); /* GN */ 00189 s->mb_x= 0; 00190 s->mb_y= s->gob_index* gob_number; 00191 gfid = get_bits(&s->gb, 2); /* GFID */ 00192 s->qscale = get_bits(&s->gb, 5); /* GQUANT */ 00193 } 00194 00195 if(s->mb_y >= s->mb_height) 00196 return -1; 00197 00198 if(s->qscale==0) 00199 return -1; 00200 00201 return 0; 00202 } 00203 00210 const uint8_t *ff_h263_find_resync_marker(const uint8_t *restrict p, const uint8_t * restrict end) 00211 { 00212 assert(p < end); 00213 00214 end-=2; 00215 p++; 00216 for(;p<end; p+=2){ 00217 if(!*p){ 00218 if (!p[-1] && p[1]) return p - 1; 00219 else if(!p[ 1] && p[2]) return p; 00220 } 00221 } 00222 return end+2; 00223 } 00224 00229 int ff_h263_resync(MpegEncContext *s){ 00230 int left, pos, ret; 00231 00232 if(s->codec_id==CODEC_ID_MPEG4){ 00233 skip_bits1(&s->gb); 00234 align_get_bits(&s->gb); 00235 } 00236 00237 if(show_bits(&s->gb, 16)==0){ 00238 pos= get_bits_count(&s->gb); 00239 if(CONFIG_MPEG4_DECODER && s->codec_id==CODEC_ID_MPEG4) 00240 ret= mpeg4_decode_video_packet_header(s); 00241 else 00242 ret= h263_decode_gob_header(s); 00243 if(ret>=0) 00244 return pos; 00245 } 00246 //OK, it's not where it is supposed to be ... 00247 s->gb= s->last_resync_gb; 00248 align_get_bits(&s->gb); 00249 left= get_bits_left(&s->gb); 00250 00251 for(;left>16+1+5+5; left-=8){ 00252 if(show_bits(&s->gb, 16)==0){ 00253 GetBitContext bak= s->gb; 00254 00255 pos= get_bits_count(&s->gb); 00256 if(CONFIG_MPEG4_DECODER && s->codec_id==CODEC_ID_MPEG4) 00257 ret= mpeg4_decode_video_packet_header(s); 00258 else 00259 ret= h263_decode_gob_header(s); 00260 if(ret>=0) 00261 return pos; 00262 00263 s->gb= bak; 00264 } 00265 skip_bits(&s->gb, 8); 00266 } 00267 00268 return -1; 00269 } 00270 00271 int h263_decode_motion(MpegEncContext * s, int pred, int f_code) 00272 { 00273 int code, val, sign, shift, l; 00274 code = get_vlc2(&s->gb, mv_vlc.table, MV_VLC_BITS, 2); 00275 00276 if (code == 0) 00277 return pred; 00278 if (code < 0) 00279 return 0xffff; 00280 00281 sign = get_bits1(&s->gb); 00282 shift = f_code - 1; 00283 val = code; 00284 if (shift) { 00285 val = (val - 1) << shift; 00286 val |= get_bits(&s->gb, shift); 00287 val++; 00288 } 00289 if (sign) 00290 val = -val; 00291 val += pred; 00292 00293 /* modulo decoding */ 00294 if (!s->h263_long_vectors) { 00295 l = INT_BIT - 5 - f_code; 00296 val = (val<<l)>>l; 00297 } else { 00298 /* horrible h263 long vector mode */ 00299 if (pred < -31 && val < -63) 00300 val += 64; 00301 if (pred > 32 && val > 63) 00302 val -= 64; 00303 00304 } 00305 return val; 00306 } 00307 00308 00309 /* Decodes RVLC of H.263+ UMV */ 00310 static int h263p_decode_umotion(MpegEncContext * s, int pred) 00311 { 00312 int code = 0, sign; 00313 00314 if (get_bits1(&s->gb)) /* Motion difference = 0 */ 00315 return pred; 00316 00317 code = 2 + get_bits1(&s->gb); 00318 00319 while (get_bits1(&s->gb)) 00320 { 00321 code <<= 1; 00322 code += get_bits1(&s->gb); 00323 } 00324 sign = code & 1; 00325 code >>= 1; 00326 00327 code = (sign) ? (pred - code) : (pred + code); 00328 dprintf(s->avctx,"H.263+ UMV Motion = %d\n", code); 00329 return code; 00330 00331 } 00332 00336 static void preview_obmc(MpegEncContext *s){ 00337 GetBitContext gb= s->gb; 00338 00339 int cbpc, i, pred_x, pred_y, mx, my; 00340 int16_t *mot_val; 00341 const int xy= s->mb_x + 1 + s->mb_y * s->mb_stride; 00342 const int stride= s->b8_stride*2; 00343 00344 for(i=0; i<4; i++) 00345 s->block_index[i]+= 2; 00346 for(i=4; i<6; i++) 00347 s->block_index[i]+= 1; 00348 s->mb_x++; 00349 00350 assert(s->pict_type == FF_P_TYPE); 00351 00352 do{ 00353 if (get_bits1(&s->gb)) { 00354 /* skip mb */ 00355 mot_val = s->current_picture.motion_val[0][ s->block_index[0] ]; 00356 mot_val[0 ]= mot_val[2 ]= 00357 mot_val[0+stride]= mot_val[2+stride]= 0; 00358 mot_val[1 ]= mot_val[3 ]= 00359 mot_val[1+stride]= mot_val[3+stride]= 0; 00360 00361 s->current_picture.mb_type[xy]= MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_L0; 00362 goto end; 00363 } 00364 cbpc = get_vlc2(&s->gb, ff_h263_inter_MCBPC_vlc.table, INTER_MCBPC_VLC_BITS, 2); 00365 }while(cbpc == 20); 00366 00367 if(cbpc & 4){ 00368 s->current_picture.mb_type[xy]= MB_TYPE_INTRA; 00369 }else{ 00370 get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1); 00371 if (cbpc & 8) { 00372 if(s->modified_quant){ 00373 if(get_bits1(&s->gb)) skip_bits(&s->gb, 1); 00374 else skip_bits(&s->gb, 5); 00375 }else 00376 skip_bits(&s->gb, 2); 00377 } 00378 00379 if ((cbpc & 16) == 0) { 00380 s->current_picture.mb_type[xy]= MB_TYPE_16x16 | MB_TYPE_L0; 00381 /* 16x16 motion prediction */ 00382 mot_val= h263_pred_motion(s, 0, 0, &pred_x, &pred_y); 00383 if (s->umvplus) 00384 mx = h263p_decode_umotion(s, pred_x); 00385 else 00386 mx = h263_decode_motion(s, pred_x, 1); 00387 00388 if (s->umvplus) 00389 my = h263p_decode_umotion(s, pred_y); 00390 else 00391 my = h263_decode_motion(s, pred_y, 1); 00392 00393 mot_val[0 ]= mot_val[2 ]= 00394 mot_val[0+stride]= mot_val[2+stride]= mx; 00395 mot_val[1 ]= mot_val[3 ]= 00396 mot_val[1+stride]= mot_val[3+stride]= my; 00397 } else { 00398 s->current_picture.mb_type[xy]= MB_TYPE_8x8 | MB_TYPE_L0; 00399 for(i=0;i<4;i++) { 00400 mot_val = h263_pred_motion(s, i, 0, &pred_x, &pred_y); 00401 if (s->umvplus) 00402 mx = h263p_decode_umotion(s, pred_x); 00403 else 00404 mx = h263_decode_motion(s, pred_x, 1); 00405 00406 if (s->umvplus) 00407 my = h263p_decode_umotion(s, pred_y); 00408 else 00409 my = h263_decode_motion(s, pred_y, 1); 00410 if (s->umvplus && (mx - pred_x) == 1 && (my - pred_y) == 1) 00411 skip_bits1(&s->gb); /* Bit stuffing to prevent PSC */ 00412 mot_val[0] = mx; 00413 mot_val[1] = my; 00414 } 00415 } 00416 } 00417 end: 00418 00419 for(i=0; i<4; i++) 00420 s->block_index[i]-= 2; 00421 for(i=4; i<6; i++) 00422 s->block_index[i]-= 1; 00423 s->mb_x--; 00424 00425 s->gb= gb; 00426 } 00427 00428 static void h263_decode_dquant(MpegEncContext *s){ 00429 static const int8_t quant_tab[4] = { -1, -2, 1, 2 }; 00430 00431 if(s->modified_quant){ 00432 if(get_bits1(&s->gb)) 00433 s->qscale= modified_quant_tab[get_bits1(&s->gb)][ s->qscale ]; 00434 else 00435 s->qscale= get_bits(&s->gb, 5); 00436 }else 00437 s->qscale += quant_tab[get_bits(&s->gb, 2)]; 00438 ff_set_qscale(s, s->qscale); 00439 } 00440 00441 static int h263_decode_block(MpegEncContext * s, DCTELEM * block, 00442 int n, int coded) 00443 { 00444 int code, level, i, j, last, run; 00445 RLTable *rl = &ff_h263_rl_inter; 00446 const uint8_t *scan_table; 00447 GetBitContext gb= s->gb; 00448 00449 scan_table = s->intra_scantable.permutated; 00450 if (s->h263_aic && s->mb_intra) { 00451 rl = &rl_intra_aic; 00452 i = 0; 00453 if (s->ac_pred) { 00454 if (s->h263_aic_dir) 00455 scan_table = s->intra_v_scantable.permutated; /* left */ 00456 else 00457 scan_table = s->intra_h_scantable.permutated; /* top */ 00458 } 00459 } else if (s->mb_intra) { 00460 /* DC coef */ 00461 if(s->codec_id == CODEC_ID_RV10){ 00462 #if CONFIG_RV10_DECODER 00463 if (s->rv10_version == 3 && s->pict_type == FF_I_TYPE) { 00464 int component, diff; 00465 component = (n <= 3 ? 0 : n - 4 + 1); 00466 level = s->last_dc[component]; 00467 if (s->rv10_first_dc_coded[component]) { 00468 diff = rv_decode_dc(s, n); 00469 if (diff == 0xffff) 00470 return -1; 00471 level += diff; 00472 level = level & 0xff; /* handle wrap round */ 00473 s->last_dc[component] = level; 00474 } else { 00475 s->rv10_first_dc_coded[component] = 1; 00476 } 00477 } else { 00478 level = get_bits(&s->gb, 8); 00479 if (level == 255) 00480 level = 128; 00481 } 00482 #endif 00483 }else{ 00484 level = get_bits(&s->gb, 8); 00485 if((level&0x7F) == 0){ 00486 av_log(s->avctx, AV_LOG_ERROR, "illegal dc %d at %d %d\n", level, s->mb_x, s->mb_y); 00487 if(s->error_recognition >= FF_ER_COMPLIANT) 00488 return -1; 00489 } 00490 if (level == 255) 00491 level = 128; 00492 } 00493 block[0] = level; 00494 i = 1; 00495 } else { 00496 i = 0; 00497 } 00498 if (!coded) { 00499 if (s->mb_intra && s->h263_aic) 00500 goto not_coded; 00501 s->block_last_index[n] = i - 1; 00502 return 0; 00503 } 00504 retry: 00505 for(;;) { 00506 code = get_vlc2(&s->gb, rl->vlc.table, TEX_VLC_BITS, 2); 00507 if (code < 0){ 00508 av_log(s->avctx, AV_LOG_ERROR, "illegal ac vlc code at %dx%d\n", s->mb_x, s->mb_y); 00509 return -1; 00510 } 00511 if (code == rl->n) { 00512 /* escape */ 00513 if (CONFIG_FLV_DECODER && s->h263_flv > 1) { 00514 ff_flv2_decode_ac_esc(&s->gb, &level, &run, &last); 00515 } else { 00516 last = get_bits1(&s->gb); 00517 run = get_bits(&s->gb, 6); 00518 level = (int8_t)get_bits(&s->gb, 8); 00519 if(level == -128){ 00520 if (s->codec_id == CODEC_ID_RV10) { 00521 /* XXX: should patch encoder too */ 00522 level = get_sbits(&s->gb, 12); 00523 }else{ 00524 level = get_bits(&s->gb, 5); 00525 level |= get_sbits(&s->gb, 6)<<5; 00526 } 00527 } 00528 } 00529 } else { 00530 run = rl->table_run[code]; 00531 level = rl->table_level[code]; 00532 last = code >= rl->last; 00533 if (get_bits1(&s->gb)) 00534 level = -level; 00535 } 00536 i += run; 00537 if (i >= 64){ 00538 if(s->alt_inter_vlc && rl == &ff_h263_rl_inter && !s->mb_intra){ 00539 //Looks like a hack but no, it's the way it is supposed to work ... 00540 rl = &rl_intra_aic; 00541 i = 0; 00542 s->gb= gb; 00543 s->dsp.clear_block(block); 00544 goto retry; 00545 } 00546 av_log(s->avctx, AV_LOG_ERROR, "run overflow at %dx%d i:%d\n", s->mb_x, s->mb_y, s->mb_intra); 00547 return -1; 00548 } 00549 j = scan_table[i]; 00550 block[j] = level; 00551 if (last) 00552 break; 00553 i++; 00554 } 00555 not_coded: 00556 if (s->mb_intra && s->h263_aic) { 00557 h263_pred_acdc(s, block, n); 00558 i = 63; 00559 } 00560 s->block_last_index[n] = i; 00561 return 0; 00562 } 00563 00564 static int h263_skip_b_part(MpegEncContext *s, int cbp) 00565 { 00566 LOCAL_ALIGNED_16(DCTELEM, dblock, [64]); 00567 int i, mbi; 00568 00569 /* we have to set s->mb_intra to zero to decode B-part of PB-frame correctly 00570 * but real value should be restored in order to be used later (in OBMC condition) 00571 */ 00572 mbi = s->mb_intra; 00573 s->mb_intra = 0; 00574 for (i = 0; i < 6; i++) { 00575 if (h263_decode_block(s, dblock, i, cbp&32) < 0) 00576 return -1; 00577 cbp+=cbp; 00578 } 00579 s->mb_intra = mbi; 00580 return 0; 00581 } 00582 00583 static int h263_get_modb(GetBitContext *gb, int pb_frame, int *cbpb) 00584 { 00585 int c, mv = 1; 00586 00587 if (pb_frame < 3) { // h.263 Annex G and i263 PB-frame 00588 c = get_bits1(gb); 00589 if (pb_frame == 2 && c) 00590 mv = !get_bits1(gb); 00591 } else { // h.263 Annex M improved PB-frame 00592 mv = get_unary(gb, 0, 4) + 1; 00593 c = mv & 1; 00594 mv = !!(mv & 2); 00595 } 00596 if(c) 00597 *cbpb = get_bits(gb, 6); 00598 return mv; 00599 } 00600 00601 int ff_h263_decode_mb(MpegEncContext *s, 00602 DCTELEM block[6][64]) 00603 { 00604 int cbpc, cbpy, i, cbp, pred_x, pred_y, mx, my, dquant; 00605 int16_t *mot_val; 00606 const int xy= s->mb_x + s->mb_y * s->mb_stride; 00607 int cbpb = 0, pb_mv_count = 0; 00608 00609 assert(!s->h263_pred); 00610 00611 if (s->pict_type == FF_P_TYPE) { 00612 do{ 00613 if (get_bits1(&s->gb)) { 00614 /* skip mb */ 00615 s->mb_intra = 0; 00616 for(i=0;i<6;i++) 00617 s->block_last_index[i] = -1; 00618 s->mv_dir = MV_DIR_FORWARD; 00619 s->mv_type = MV_TYPE_16X16; 00620 s->current_picture.mb_type[xy]= MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_L0; 00621 s->mv[0][0][0] = 0; 00622 s->mv[0][0][1] = 0; 00623 s->mb_skipped = !(s->obmc | s->loop_filter); 00624 goto end; 00625 } 00626 cbpc = get_vlc2(&s->gb, ff_h263_inter_MCBPC_vlc.table, INTER_MCBPC_VLC_BITS, 2); 00627 if (cbpc < 0){ 00628 av_log(s->avctx, AV_LOG_ERROR, "cbpc damaged at %d %d\n", s->mb_x, s->mb_y); 00629 return -1; 00630 } 00631 }while(cbpc == 20); 00632 00633 s->dsp.clear_blocks(s->block[0]); 00634 00635 dquant = cbpc & 8; 00636 s->mb_intra = ((cbpc & 4) != 0); 00637 if (s->mb_intra) goto intra; 00638 00639 if(s->pb_frame && get_bits1(&s->gb)) 00640 pb_mv_count = h263_get_modb(&s->gb, s->pb_frame, &cbpb); 00641 cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1); 00642 00643 if(s->alt_inter_vlc==0 || (cbpc & 3)!=3) 00644 cbpy ^= 0xF; 00645 00646 cbp = (cbpc & 3) | (cbpy << 2); 00647 if (dquant) { 00648 h263_decode_dquant(s); 00649 } 00650 00651 s->mv_dir = MV_DIR_FORWARD; 00652 if ((cbpc & 16) == 0) { 00653 s->current_picture.mb_type[xy]= MB_TYPE_16x16 | MB_TYPE_L0; 00654 /* 16x16 motion prediction */ 00655 s->mv_type = MV_TYPE_16X16; 00656 h263_pred_motion(s, 0, 0, &pred_x, &pred_y); 00657 if (s->umvplus) 00658 mx = h263p_decode_umotion(s, pred_x); 00659 else 00660 mx = h263_decode_motion(s, pred_x, 1); 00661 00662 if (mx >= 0xffff) 00663 return -1; 00664 00665 if (s->umvplus) 00666 my = h263p_decode_umotion(s, pred_y); 00667 else 00668 my = h263_decode_motion(s, pred_y, 1); 00669 00670 if (my >= 0xffff) 00671 return -1; 00672 s->mv[0][0][0] = mx; 00673 s->mv[0][0][1] = my; 00674 00675 if (s->umvplus && (mx - pred_x) == 1 && (my - pred_y) == 1) 00676 skip_bits1(&s->gb); /* Bit stuffing to prevent PSC */ 00677 } else { 00678 s->current_picture.mb_type[xy]= MB_TYPE_8x8 | MB_TYPE_L0; 00679 s->mv_type = MV_TYPE_8X8; 00680 for(i=0;i<4;i++) { 00681 mot_val = h263_pred_motion(s, i, 0, &pred_x, &pred_y); 00682 if (s->umvplus) 00683 mx = h263p_decode_umotion(s, pred_x); 00684 else 00685 mx = h263_decode_motion(s, pred_x, 1); 00686 if (mx >= 0xffff) 00687 return -1; 00688 00689 if (s->umvplus) 00690 my = h263p_decode_umotion(s, pred_y); 00691 else 00692 my = h263_decode_motion(s, pred_y, 1); 00693 if (my >= 0xffff) 00694 return -1; 00695 s->mv[0][i][0] = mx; 00696 s->mv[0][i][1] = my; 00697 if (s->umvplus && (mx - pred_x) == 1 && (my - pred_y) == 1) 00698 skip_bits1(&s->gb); /* Bit stuffing to prevent PSC */ 00699 mot_val[0] = mx; 00700 mot_val[1] = my; 00701 } 00702 } 00703 } else if(s->pict_type==FF_B_TYPE) { 00704 int mb_type; 00705 const int stride= s->b8_stride; 00706 int16_t *mot_val0 = s->current_picture.motion_val[0][ 2*(s->mb_x + s->mb_y*stride) ]; 00707 int16_t *mot_val1 = s->current_picture.motion_val[1][ 2*(s->mb_x + s->mb_y*stride) ]; 00708 // const int mv_xy= s->mb_x + 1 + s->mb_y * s->mb_stride; 00709 00710 //FIXME ugly 00711 mot_val0[0 ]= mot_val0[2 ]= mot_val0[0+2*stride]= mot_val0[2+2*stride]= 00712 mot_val0[1 ]= mot_val0[3 ]= mot_val0[1+2*stride]= mot_val0[3+2*stride]= 00713 mot_val1[0 ]= mot_val1[2 ]= mot_val1[0+2*stride]= mot_val1[2+2*stride]= 00714 mot_val1[1 ]= mot_val1[3 ]= mot_val1[1+2*stride]= mot_val1[3+2*stride]= 0; 00715 00716 do{ 00717 mb_type= get_vlc2(&s->gb, h263_mbtype_b_vlc.table, H263_MBTYPE_B_VLC_BITS, 2); 00718 if (mb_type < 0){ 00719 av_log(s->avctx, AV_LOG_ERROR, "b mb_type damaged at %d %d\n", s->mb_x, s->mb_y); 00720 return -1; 00721 } 00722 00723 mb_type= h263_mb_type_b_map[ mb_type ]; 00724 }while(!mb_type); 00725 00726 s->mb_intra = IS_INTRA(mb_type); 00727 if(HAS_CBP(mb_type)){ 00728 s->dsp.clear_blocks(s->block[0]); 00729 cbpc = get_vlc2(&s->gb, cbpc_b_vlc.table, CBPC_B_VLC_BITS, 1); 00730 if(s->mb_intra){ 00731 dquant = IS_QUANT(mb_type); 00732 goto intra; 00733 } 00734 00735 cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1); 00736 00737 if (cbpy < 0){ 00738 av_log(s->avctx, AV_LOG_ERROR, "b cbpy damaged at %d %d\n", s->mb_x, s->mb_y); 00739 return -1; 00740 } 00741 00742 if(s->alt_inter_vlc==0 || (cbpc & 3)!=3) 00743 cbpy ^= 0xF; 00744 00745 cbp = (cbpc & 3) | (cbpy << 2); 00746 }else 00747 cbp=0; 00748 00749 assert(!s->mb_intra); 00750 00751 if(IS_QUANT(mb_type)){ 00752 h263_decode_dquant(s); 00753 } 00754 00755 if(IS_DIRECT(mb_type)){ 00756 s->mv_dir = MV_DIR_FORWARD | MV_DIR_BACKWARD | MV_DIRECT; 00757 mb_type |= ff_mpeg4_set_direct_mv(s, 0, 0); 00758 }else{ 00759 s->mv_dir = 0; 00760 s->mv_type= MV_TYPE_16X16; 00761 //FIXME UMV 00762 00763 if(USES_LIST(mb_type, 0)){ 00764 int16_t *mot_val= h263_pred_motion(s, 0, 0, &mx, &my); 00765 s->mv_dir = MV_DIR_FORWARD; 00766 00767 mx = h263_decode_motion(s, mx, 1); 00768 my = h263_decode_motion(s, my, 1); 00769 00770 s->mv[0][0][0] = mx; 00771 s->mv[0][0][1] = my; 00772 mot_val[0 ]= mot_val[2 ]= mot_val[0+2*stride]= mot_val[2+2*stride]= mx; 00773 mot_val[1 ]= mot_val[3 ]= mot_val[1+2*stride]= mot_val[3+2*stride]= my; 00774 } 00775 00776 if(USES_LIST(mb_type, 1)){ 00777 int16_t *mot_val= h263_pred_motion(s, 0, 1, &mx, &my); 00778 s->mv_dir |= MV_DIR_BACKWARD; 00779 00780 mx = h263_decode_motion(s, mx, 1); 00781 my = h263_decode_motion(s, my, 1); 00782 00783 s->mv[1][0][0] = mx; 00784 s->mv[1][0][1] = my; 00785 mot_val[0 ]= mot_val[2 ]= mot_val[0+2*stride]= mot_val[2+2*stride]= mx; 00786 mot_val[1 ]= mot_val[3 ]= mot_val[1+2*stride]= mot_val[3+2*stride]= my; 00787 } 00788 } 00789 00790 s->current_picture.mb_type[xy]= mb_type; 00791 } else { /* I-Frame */ 00792 do{ 00793 cbpc = get_vlc2(&s->gb, ff_h263_intra_MCBPC_vlc.table, INTRA_MCBPC_VLC_BITS, 2); 00794 if (cbpc < 0){ 00795 av_log(s->avctx, AV_LOG_ERROR, "I cbpc damaged at %d %d\n", s->mb_x, s->mb_y); 00796 return -1; 00797 } 00798 }while(cbpc == 8); 00799 00800 s->dsp.clear_blocks(s->block[0]); 00801 00802 dquant = cbpc & 4; 00803 s->mb_intra = 1; 00804 intra: 00805 s->current_picture.mb_type[xy]= MB_TYPE_INTRA; 00806 if (s->h263_aic) { 00807 s->ac_pred = get_bits1(&s->gb); 00808 if(s->ac_pred){ 00809 s->current_picture.mb_type[xy]= MB_TYPE_INTRA | MB_TYPE_ACPRED; 00810 00811 s->h263_aic_dir = get_bits1(&s->gb); 00812 } 00813 }else 00814 s->ac_pred = 0; 00815 00816 if(s->pb_frame && get_bits1(&s->gb)) 00817 pb_mv_count = h263_get_modb(&s->gb, s->pb_frame, &cbpb); 00818 cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1); 00819 if(cbpy<0){ 00820 av_log(s->avctx, AV_LOG_ERROR, "I cbpy damaged at %d %d\n", s->mb_x, s->mb_y); 00821 return -1; 00822 } 00823 cbp = (cbpc & 3) | (cbpy << 2); 00824 if (dquant) { 00825 h263_decode_dquant(s); 00826 } 00827 00828 pb_mv_count += !!s->pb_frame; 00829 } 00830 00831 while(pb_mv_count--){ 00832 h263_decode_motion(s, 0, 1); 00833 h263_decode_motion(s, 0, 1); 00834 } 00835 00836 /* decode each block */ 00837 for (i = 0; i < 6; i++) { 00838 if (h263_decode_block(s, block[i], i, cbp&32) < 0) 00839 return -1; 00840 cbp+=cbp; 00841 } 00842 00843 if(s->pb_frame && h263_skip_b_part(s, cbpb) < 0) 00844 return -1; 00845 if(s->obmc && !s->mb_intra){ 00846 if(s->pict_type == FF_P_TYPE && s->mb_x+1<s->mb_width && s->mb_num_left != 1) 00847 preview_obmc(s); 00848 } 00849 end: 00850 00851 /* per-MB end of slice check */ 00852 { 00853 int v= show_bits(&s->gb, 16); 00854 00855 if(get_bits_count(&s->gb) + 16 > s->gb.size_in_bits){ 00856 v>>= get_bits_count(&s->gb) + 16 - s->gb.size_in_bits; 00857 } 00858 00859 if(v==0) 00860 return SLICE_END; 00861 } 00862 00863 return SLICE_OK; 00864 } 00865 00866 /* most is hardcoded. should extend to handle all h263 streams */ 00867 int h263_decode_picture_header(MpegEncContext *s) 00868 { 00869 int format, width, height, i; 00870 uint32_t startcode; 00871 00872 align_get_bits(&s->gb); 00873 00874 startcode= get_bits(&s->gb, 22-8); 00875 00876 for(i= get_bits_left(&s->gb); i>24; i-=8) { 00877 startcode = ((startcode << 8) | get_bits(&s->gb, 8)) & 0x003FFFFF; 00878 00879 if(startcode == 0x20) 00880 break; 00881 } 00882 00883 if (startcode != 0x20) { 00884 av_log(s->avctx, AV_LOG_ERROR, "Bad picture start code\n"); 00885 return -1; 00886 } 00887 /* temporal reference */ 00888 i = get_bits(&s->gb, 8); /* picture timestamp */ 00889 if( (s->picture_number&~0xFF)+i < s->picture_number) 00890 i+= 256; 00891 s->current_picture_ptr->pts= 00892 s->picture_number= (s->picture_number&~0xFF) + i; 00893 00894 /* PTYPE starts here */ 00895 if (get_bits1(&s->gb) != 1) { 00896 /* marker */ 00897 av_log(s->avctx, AV_LOG_ERROR, "Bad marker\n"); 00898 return -1; 00899 } 00900 if (get_bits1(&s->gb) != 0) { 00901 av_log(s->avctx, AV_LOG_ERROR, "Bad H263 id\n"); 00902 return -1; /* h263 id */ 00903 } 00904 skip_bits1(&s->gb); /* split screen off */ 00905 skip_bits1(&s->gb); /* camera off */ 00906 skip_bits1(&s->gb); /* freeze picture release off */ 00907 00908 format = get_bits(&s->gb, 3); 00909 /* 00910 0 forbidden 00911 1 sub-QCIF 00912 10 QCIF 00913 7 extended PTYPE (PLUSPTYPE) 00914 */ 00915 00916 if (format != 7 && format != 6) { 00917 s->h263_plus = 0; 00918 /* H.263v1 */ 00919 width = h263_format[format][0]; 00920 height = h263_format[format][1]; 00921 if (!width) 00922 return -1; 00923 00924 s->pict_type = FF_I_TYPE + get_bits1(&s->gb); 00925 00926 s->h263_long_vectors = get_bits1(&s->gb); 00927 00928 if (get_bits1(&s->gb) != 0) { 00929 av_log(s->avctx, AV_LOG_ERROR, "H263 SAC not supported\n"); 00930 return -1; /* SAC: off */ 00931 } 00932 s->obmc= get_bits1(&s->gb); /* Advanced prediction mode */ 00933 s->unrestricted_mv = s->h263_long_vectors || s->obmc; 00934 00935 s->pb_frame = get_bits1(&s->gb); 00936 s->chroma_qscale= s->qscale = get_bits(&s->gb, 5); 00937 skip_bits1(&s->gb); /* Continuous Presence Multipoint mode: off */ 00938 00939 s->width = width; 00940 s->height = height; 00941 s->avctx->sample_aspect_ratio= (AVRational){12,11}; 00942 s->avctx->time_base= (AVRational){1001, 30000}; 00943 } else { 00944 int ufep; 00945 00946 /* H.263v2 */ 00947 s->h263_plus = 1; 00948 ufep = get_bits(&s->gb, 3); /* Update Full Extended PTYPE */ 00949 00950 /* ufep other than 0 and 1 are reserved */ 00951 if (ufep == 1) { 00952 /* OPPTYPE */ 00953 format = get_bits(&s->gb, 3); 00954 dprintf(s->avctx, "ufep=1, format: %d\n", format); 00955 s->custom_pcf= get_bits1(&s->gb); 00956 s->umvplus = get_bits1(&s->gb); /* Unrestricted Motion Vector */ 00957 if (get_bits1(&s->gb) != 0) { 00958 av_log(s->avctx, AV_LOG_ERROR, "Syntax-based Arithmetic Coding (SAC) not supported\n"); 00959 } 00960 s->obmc= get_bits1(&s->gb); /* Advanced prediction mode */ 00961 s->h263_aic = get_bits1(&s->gb); /* Advanced Intra Coding (AIC) */ 00962 s->loop_filter= get_bits1(&s->gb); 00963 s->unrestricted_mv = s->umvplus || s->obmc || s->loop_filter; 00964 00965 s->h263_slice_structured= get_bits1(&s->gb); 00966 if (get_bits1(&s->gb) != 0) { 00967 av_log(s->avctx, AV_LOG_ERROR, "Reference Picture Selection not supported\n"); 00968 } 00969 if (get_bits1(&s->gb) != 0) { 00970 av_log(s->avctx, AV_LOG_ERROR, "Independent Segment Decoding not supported\n"); 00971 } 00972 s->alt_inter_vlc= get_bits1(&s->gb); 00973 s->modified_quant= get_bits1(&s->gb); 00974 if(s->modified_quant) 00975 s->chroma_qscale_table= ff_h263_chroma_qscale_table; 00976 00977 skip_bits(&s->gb, 1); /* Prevent start code emulation */ 00978 00979 skip_bits(&s->gb, 3); /* Reserved */ 00980 } else if (ufep != 0) { 00981 av_log(s->avctx, AV_LOG_ERROR, "Bad UFEP type (%d)\n", ufep); 00982 return -1; 00983 } 00984 00985 /* MPPTYPE */ 00986 s->pict_type = get_bits(&s->gb, 3); 00987 switch(s->pict_type){ 00988 case 0: s->pict_type= FF_I_TYPE;break; 00989 case 1: s->pict_type= FF_P_TYPE;break; 00990 case 2: s->pict_type= FF_P_TYPE;s->pb_frame = 3;break; 00991 case 3: s->pict_type= FF_B_TYPE;break; 00992 case 7: s->pict_type= FF_I_TYPE;break; //ZYGO 00993 default: 00994 return -1; 00995 } 00996 skip_bits(&s->gb, 2); 00997 s->no_rounding = get_bits1(&s->gb); 00998 skip_bits(&s->gb, 4); 00999 01000 /* Get the picture dimensions */ 01001 if (ufep) { 01002 if (format == 6) { 01003 /* Custom Picture Format (CPFMT) */ 01004 s->aspect_ratio_info = get_bits(&s->gb, 4); 01005 dprintf(s->avctx, "aspect: %d\n", s->aspect_ratio_info); 01006 /* aspect ratios: 01007 0 - forbidden 01008 1 - 1:1 01009 2 - 12:11 (CIF 4:3) 01010 3 - 10:11 (525-type 4:3) 01011 4 - 16:11 (CIF 16:9) 01012 5 - 40:33 (525-type 16:9) 01013 6-14 - reserved 01014 */ 01015 width = (get_bits(&s->gb, 9) + 1) * 4; 01016 skip_bits1(&s->gb); 01017 height = get_bits(&s->gb, 9) * 4; 01018 dprintf(s->avctx, "\nH.263+ Custom picture: %dx%d\n",width,height); 01019 if (s->aspect_ratio_info == FF_ASPECT_EXTENDED) { 01020 /* aspected dimensions */ 01021 s->avctx->sample_aspect_ratio.num= get_bits(&s->gb, 8); 01022 s->avctx->sample_aspect_ratio.den= get_bits(&s->gb, 8); 01023 }else{ 01024 s->avctx->sample_aspect_ratio= ff_h263_pixel_aspect[s->aspect_ratio_info]; 01025 } 01026 } else { 01027 width = h263_format[format][0]; 01028 height = h263_format[format][1]; 01029 s->avctx->sample_aspect_ratio= (AVRational){12,11}; 01030 } 01031 if ((width == 0) || (height == 0)) 01032 return -1; 01033 s->width = width; 01034 s->height = height; 01035 01036 if(s->custom_pcf){ 01037 int gcd; 01038 s->avctx->time_base.den= 1800000; 01039 s->avctx->time_base.num= 1000 + get_bits1(&s->gb); 01040 s->avctx->time_base.num*= get_bits(&s->gb, 7); 01041 if(s->avctx->time_base.num == 0){ 01042 av_log(s, AV_LOG_ERROR, "zero framerate\n"); 01043 return -1; 01044 } 01045 gcd= av_gcd(s->avctx->time_base.den, s->avctx->time_base.num); 01046 s->avctx->time_base.den /= gcd; 01047 s->avctx->time_base.num /= gcd; 01048 }else{ 01049 s->avctx->time_base= (AVRational){1001, 30000}; 01050 } 01051 } 01052 01053 if(s->custom_pcf){ 01054 skip_bits(&s->gb, 2); //extended Temporal reference 01055 } 01056 01057 if (ufep) { 01058 if (s->umvplus) { 01059 if(get_bits1(&s->gb)==0) /* Unlimited Unrestricted Motion Vectors Indicator (UUI) */ 01060 skip_bits1(&s->gb); 01061 } 01062 if(s->h263_slice_structured){ 01063 if (get_bits1(&s->gb) != 0) { 01064 av_log(s->avctx, AV_LOG_ERROR, "rectangular slices not supported\n"); 01065 } 01066 if (get_bits1(&s->gb) != 0) { 01067 av_log(s->avctx, AV_LOG_ERROR, "unordered slices not supported\n"); 01068 } 01069 } 01070 } 01071 01072 s->qscale = get_bits(&s->gb, 5); 01073 } 01074 01075 s->mb_width = (s->width + 15) / 16; 01076 s->mb_height = (s->height + 15) / 16; 01077 s->mb_num = s->mb_width * s->mb_height; 01078 01079 if (s->pb_frame) { 01080 skip_bits(&s->gb, 3); /* Temporal reference for B-pictures */ 01081 if (s->custom_pcf) 01082 skip_bits(&s->gb, 2); //extended Temporal reference 01083 skip_bits(&s->gb, 2); /* Quantization information for B-pictures */ 01084 } 01085 01086 /* PEI */ 01087 while (get_bits1(&s->gb) != 0) { 01088 skip_bits(&s->gb, 8); 01089 } 01090 01091 if(s->h263_slice_structured){ 01092 if (get_bits1(&s->gb) != 1) { 01093 av_log(s->avctx, AV_LOG_ERROR, "SEPB1 marker missing\n"); 01094 return -1; 01095 } 01096 01097 ff_h263_decode_mba(s); 01098 01099 if (get_bits1(&s->gb) != 1) { 01100 av_log(s->avctx, AV_LOG_ERROR, "SEPB2 marker missing\n"); 01101 return -1; 01102 } 01103 } 01104 s->f_code = 1; 01105 01106 if(s->h263_aic){ 01107 s->y_dc_scale_table= 01108 s->c_dc_scale_table= ff_aic_dc_scale_table; 01109 }else{ 01110 s->y_dc_scale_table= 01111 s->c_dc_scale_table= ff_mpeg1_dc_scale_table; 01112 } 01113 01114 ff_h263_show_pict_info(s); 01115 if (s->pict_type == FF_I_TYPE && s->codec_tag == AV_RL32("ZYGO")){ 01116 int i,j; 01117 for(i=0; i<85; i++) av_log(s->avctx, AV_LOG_DEBUG, "%d", get_bits1(&s->gb)); 01118 av_log(s->avctx, AV_LOG_DEBUG, "\n"); 01119 for(i=0; i<13; i++){ 01120 for(j=0; j<3; j++){ 01121 int v= get_bits(&s->gb, 8); 01122 v |= get_sbits(&s->gb, 8)<<8; 01123 av_log(s->avctx, AV_LOG_DEBUG, " %5d", v); 01124 } 01125 av_log(s->avctx, AV_LOG_DEBUG, "\n"); 01126 } 01127 for(i=0; i<50; i++) av_log(s->avctx, AV_LOG_DEBUG, "%d", get_bits1(&s->gb)); 01128 } 01129 01130 return 0; 01131 }