/* * ITU H263 bitstream decoder * Copyright (c) 2000,2001 Fabrice Bellard * H263+ support. * Copyright (c) 2001 Juan J. Sierralta P * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at> * * This file is part of FFmpeg. * * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * FFmpeg is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ /** * @file * h263 decoder. */ #define UNCHECKED_BITSTREAM_READER 1 #include <limits.h> #include "libavutil/attributes.h" #include "libavutil/imgutils.h" #include "libavutil/internal.h" #include "libavutil/mathematics.h" #include "avcodec.h" #include "mpegvideo.h" #include "h263.h" #include "h263data.h" #include "internal.h" #include "mathops.h" #include "mpegutils.h" #include "unary.h" #include "flv.h" #include "rv10.h" #include "mpeg4video.h" #include "mpegvideodata.h" // The defines below define the number of bits that are read at once for // reading vlc values. Changing these may improve speed and data cache needs // be aware though that decreasing them may need the number of stages that is // passed to get_vlc* to be increased. #define MV_VLC_BITS 9 #define H263_MBTYPE_B_VLC_BITS 6 #define CBPC_B_VLC_BITS 3 static const int h263_mb_type_b_map[15]= { MB_TYPE_DIRECT2 | MB_TYPE_L0L1, MB_TYPE_DIRECT2 | MB_TYPE_L0L1 | MB_TYPE_CBP, MB_TYPE_DIRECT2 | MB_TYPE_L0L1 | MB_TYPE_CBP | MB_TYPE_QUANT, MB_TYPE_L0 | MB_TYPE_16x16, MB_TYPE_L0 | MB_TYPE_CBP | MB_TYPE_16x16, MB_TYPE_L0 | MB_TYPE_CBP | MB_TYPE_QUANT | MB_TYPE_16x16, MB_TYPE_L1 | MB_TYPE_16x16, MB_TYPE_L1 | MB_TYPE_CBP | MB_TYPE_16x16, MB_TYPE_L1 | MB_TYPE_CBP | MB_TYPE_QUANT | MB_TYPE_16x16, MB_TYPE_L0L1 | MB_TYPE_16x16, MB_TYPE_L0L1 | MB_TYPE_CBP | MB_TYPE_16x16, MB_TYPE_L0L1 | MB_TYPE_CBP | MB_TYPE_QUANT | MB_TYPE_16x16, 0, //stuffing MB_TYPE_INTRA4x4 | MB_TYPE_CBP, MB_TYPE_INTRA4x4 | MB_TYPE_CBP | MB_TYPE_QUANT, }; void ff_h263_show_pict_info(MpegEncContext *s){ if(s->avctx->debug&FF_DEBUG_PICT_INFO){ 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", s->qscale, av_get_picture_type_char(s->pict_type), s->gb.size_in_bits, 1-s->no_rounding, s->obmc ? " AP" : "", s->umvplus ? " UMV" : "", s->h263_long_vectors ? " LONG" : "", s->h263_plus ? " +" : "", s->h263_aic ? " AIC" : "", s->alt_inter_vlc ? " AIV" : "", s->modified_quant ? " MQ" : "", s->loop_filter ? " LOOP" : "", s->h263_slice_structured ? " SS" : "", s->avctx->framerate.num, s->avctx->framerate.den ); } } /***********************************************/ /* decoding */ VLC ff_h263_intra_MCBPC_vlc; VLC ff_h263_inter_MCBPC_vlc; VLC ff_h263_cbpy_vlc; static VLC mv_vlc; static VLC h263_mbtype_b_vlc; static VLC cbpc_b_vlc; /* init vlcs */ /* XXX: find a better solution to handle static init */ av_cold void ff_h263_decode_init_vlc(void) { static volatile int done = 0; if (!done) { INIT_VLC_STATIC(&ff_h263_intra_MCBPC_vlc, INTRA_MCBPC_VLC_BITS, 9, ff_h263_intra_MCBPC_bits, 1, 1, ff_h263_intra_MCBPC_code, 1, 1, 72); INIT_VLC_STATIC(&ff_h263_inter_MCBPC_vlc, INTER_MCBPC_VLC_BITS, 28, ff_h263_inter_MCBPC_bits, 1, 1, ff_h263_inter_MCBPC_code, 1, 1, 198); INIT_VLC_STATIC(&ff_h263_cbpy_vlc, CBPY_VLC_BITS, 16, &ff_h263_cbpy_tab[0][1], 2, 1, &ff_h263_cbpy_tab[0][0], 2, 1, 64); INIT_VLC_STATIC(&mv_vlc, MV_VLC_BITS, 33, &ff_mvtab[0][1], 2, 1, &ff_mvtab[0][0], 2, 1, 538); ff_rl_init(&ff_h263_rl_inter, ff_h263_static_rl_table_store[0]); ff_rl_init(&ff_rl_intra_aic, ff_h263_static_rl_table_store[1]); INIT_VLC_RL(ff_h263_rl_inter, 554); INIT_VLC_RL(ff_rl_intra_aic, 554); INIT_VLC_STATIC(&h263_mbtype_b_vlc, H263_MBTYPE_B_VLC_BITS, 15, &ff_h263_mbtype_b_tab[0][1], 2, 1, &ff_h263_mbtype_b_tab[0][0], 2, 1, 80); INIT_VLC_STATIC(&cbpc_b_vlc, CBPC_B_VLC_BITS, 4, &ff_cbpc_b_tab[0][1], 2, 1, &ff_cbpc_b_tab[0][0], 2, 1, 8); done = 1; } } int ff_h263_decode_mba(MpegEncContext *s) { int i, mb_pos; for (i = 0; i < 6; i++) if (s->mb_num - 1 <= ff_mba_max[i]) break; mb_pos = get_bits(&s->gb, ff_mba_length[i]); s->mb_x = mb_pos % s->mb_width; s->mb_y = mb_pos / s->mb_width; return mb_pos; } /** * Decode the group of blocks header or slice header. * @return <0 if an error occurred */ static int h263_decode_gob_header(MpegEncContext *s) { unsigned int val, gob_number; int left; /* Check for GOB Start Code */ val = show_bits(&s->gb, 16); if(val) return -1; /* We have a GBSC probably with GSTUFF */ skip_bits(&s->gb, 16); /* Drop the zeros */ left= get_bits_left(&s->gb); //MN: we must check the bits left or we might end in an infinite loop (or segfault) for(;left>13; left--){ if(get_bits1(&s->gb)) break; /* Seek the '1' bit */ } if(left<=13) return -1; if(s->h263_slice_structured){ if(check_marker(&s->gb, "before MBA")==0) return -1; ff_h263_decode_mba(s); if(s->mb_num > 1583) if(check_marker(&s->gb, "after MBA")==0) return -1; s->qscale = get_bits(&s->gb, 5); /* SQUANT */ if(check_marker(&s->gb, "after SQUANT")==0) return -1; skip_bits(&s->gb, 2); /* GFID */ }else{ gob_number = get_bits(&s->gb, 5); /* GN */ s->mb_x= 0; s->mb_y= s->gob_index* gob_number; skip_bits(&s->gb, 2); /* GFID */ s->qscale = get_bits(&s->gb, 5); /* GQUANT */ } if(s->mb_y >= s->mb_height) return -1; if(s->qscale==0) return -1; return 0; } /** * Decode the group of blocks / video packet header. * @return bit position of the resync_marker, or <0 if none was found */ int ff_h263_resync(MpegEncContext *s){ int left, pos, ret; if(s->codec_id==AV_CODEC_ID_MPEG4){ skip_bits1(&s->gb); align_get_bits(&s->gb); } if(show_bits(&s->gb, 16)==0){ pos= get_bits_count(&s->gb); if(CONFIG_MPEG4_DECODER && s->codec_id==AV_CODEC_ID_MPEG4) ret= ff_mpeg4_decode_video_packet_header(s->avctx->priv_data); else ret= h263_decode_gob_header(s); if(ret>=0) return pos; } //OK, it's not where it is supposed to be ... s->gb= s->last_resync_gb; align_get_bits(&s->gb); left= get_bits_left(&s->gb); for(;left>16+1+5+5; left-=8){ if(show_bits(&s->gb, 16)==0){ GetBitContext bak= s->gb; pos= get_bits_count(&s->gb); if(CONFIG_MPEG4_DECODER && s->codec_id==AV_CODEC_ID_MPEG4) ret= ff_mpeg4_decode_video_packet_header(s->avctx->priv_data); else ret= h263_decode_gob_header(s); if(ret>=0) return pos; s->gb= bak; } skip_bits(&s->gb, 8); } return -1; } int ff_h263_decode_motion(MpegEncContext * s, int pred, int f_code) { int code, val, sign, shift; code = get_vlc2(&s->gb, mv_vlc.table, MV_VLC_BITS, 2); if (code == 0) return pred; if (code < 0) return 0xffff; sign = get_bits1(&s->gb); shift = f_code - 1; val = code; if (shift) { val = (val - 1) << shift; val |= get_bits(&s->gb, shift); val++; } if (sign) val = -val; val += pred; /* modulo decoding */ if (!s->h263_long_vectors) { val = sign_extend(val, 5 + f_code); } else { /* horrible h263 long vector mode */ if (pred < -31 && val < -63) val += 64; if (pred > 32 && val > 63) val -= 64; } return val; } /* Decode RVLC of H.263+ UMV */ static int h263p_decode_umotion(MpegEncContext * s, int pred) { int code = 0, sign; if (get_bits1(&s->gb)) /* Motion difference = 0 */ return pred; code = 2 + get_bits1(&s->gb); while (get_bits1(&s->gb)) { code <<= 1; code += get_bits1(&s->gb); } sign = code & 1; code >>= 1; code = (sign) ? (pred - code) : (pred + code); ff_tlog(s->avctx,"H.263+ UMV Motion = %d\n", code); return code; } /** * read the next MVs for OBMC. yes this is an ugly hack, feel free to send a patch :) */ static void preview_obmc(MpegEncContext *s){ GetBitContext gb= s->gb; int cbpc, i, pred_x, pred_y, mx, my; int16_t *mot_val; const int xy= s->mb_x + 1 + s->mb_y * s->mb_stride; const int stride= s->b8_stride*2; for(i=0; i<4; i++) s->block_index[i]+= 2; for(i=4; i<6; i++) s->block_index[i]+= 1; s->mb_x++; av_assert2(s->pict_type == AV_PICTURE_TYPE_P); do{ if (get_bits1(&s->gb)) { /* skip mb */ mot_val = s->current_picture.motion_val[0][s->block_index[0]]; mot_val[0 ]= mot_val[2 ]= mot_val[0+stride]= mot_val[2+stride]= 0; mot_val[1 ]= mot_val[3 ]= mot_val[1+stride]= mot_val[3+stride]= 0; s->current_picture.mb_type[xy] = MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_L0; goto end; } cbpc = get_vlc2(&s->gb, ff_h263_inter_MCBPC_vlc.table, INTER_MCBPC_VLC_BITS, 2); }while(cbpc == 20); if(cbpc & 4){ s->current_picture.mb_type[xy] = MB_TYPE_INTRA; }else{ get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1); if (cbpc & 8) { if(s->modified_quant){ if(get_bits1(&s->gb)) skip_bits(&s->gb, 1); else skip_bits(&s->gb, 5); }else skip_bits(&s->gb, 2); } if ((cbpc & 16) == 0) { s->current_picture.mb_type[xy] = MB_TYPE_16x16 | MB_TYPE_L0; /* 16x16 motion prediction */ mot_val= ff_h263_pred_motion(s, 0, 0, &pred_x, &pred_y); if (s->umvplus) mx = h263p_decode_umotion(s, pred_x); else mx = ff_h263_decode_motion(s, pred_x, 1); if (s->umvplus) my = h263p_decode_umotion(s, pred_y); else my = ff_h263_decode_motion(s, pred_y, 1); mot_val[0 ]= mot_val[2 ]= mot_val[0+stride]= mot_val[2+stride]= mx; mot_val[1 ]= mot_val[3 ]= mot_val[1+stride]= mot_val[3+stride]= my; } else { s->current_picture.mb_type[xy] = MB_TYPE_8x8 | MB_TYPE_L0; for(i=0;i<4;i++) { mot_val = ff_h263_pred_motion(s, i, 0, &pred_x, &pred_y); if (s->umvplus) mx = h263p_decode_umotion(s, pred_x); else mx = ff_h263_decode_motion(s, pred_x, 1); if (s->umvplus) my = h263p_decode_umotion(s, pred_y); else my = ff_h263_decode_motion(s, pred_y, 1); if (s->umvplus && (mx - pred_x) == 1 && (my - pred_y) == 1) skip_bits1(&s->gb); /* Bit stuffing to prevent PSC */ mot_val[0] = mx; mot_val[1] = my; } } } end: for(i=0; i<4; i++) s->block_index[i]-= 2; for(i=4; i<6; i++) s->block_index[i]-= 1; s->mb_x--; s->gb= gb; } static void h263_decode_dquant(MpegEncContext *s){ static const int8_t quant_tab[4] = { -1, -2, 1, 2 }; if(s->modified_quant){ if(get_bits1(&s->gb)) s->qscale= ff_modified_quant_tab[get_bits1(&s->gb)][ s->qscale ]; else s->qscale= get_bits(&s->gb, 5); }else s->qscale += quant_tab[get_bits(&s->gb, 2)]; ff_set_qscale(s, s->qscale); } static int h263_decode_block(MpegEncContext * s, int16_t * block, int n, int coded) { int level, i, j, run; RLTable *rl = &ff_h263_rl_inter; const uint8_t *scan_table; GetBitContext gb= s->gb; scan_table = s->intra_scantable.permutated; if (s->h263_aic && s->mb_intra) { rl = &ff_rl_intra_aic; i = 0; if (s->ac_pred) { if (s->h263_aic_dir) scan_table = s->intra_v_scantable.permutated; /* left */ else scan_table = s->intra_h_scantable.permutated; /* top */ } } else if (s->mb_intra) { /* DC coef */ if (CONFIG_RV10_DECODER && s->codec_id == AV_CODEC_ID_RV10) { if (s->rv10_version == 3 && s->pict_type == AV_PICTURE_TYPE_I) { int component, diff; component = (n <= 3 ? 0 : n - 4 + 1); level = s->last_dc[component]; if (s->rv10_first_dc_coded[component]) { diff = ff_rv_decode_dc(s, n); if (diff == 0xffff) return -1; level += diff; level = level & 0xff; /* handle wrap round */ s->last_dc[component] = level; } else { s->rv10_first_dc_coded[component] = 1; } } else { level = get_bits(&s->gb, 8); if (level == 255) level = 128; } }else{ level = get_bits(&s->gb, 8); if((level&0x7F) == 0){ av_log(s->avctx, AV_LOG_ERROR, "illegal dc %d at %d %d\n", level, s->mb_x, s->mb_y); if (s->avctx->err_recognition & (AV_EF_BITSTREAM|AV_EF_COMPLIANT)) return -1; } if (level == 255) level = 128; } block[0] = level; i = 1; } else { i = 0; } if (!coded) { if (s->mb_intra && s->h263_aic) goto not_coded; s->block_last_index[n] = i - 1; return 0; } retry: { OPEN_READER(re, &s->gb); i--; // offset by -1 to allow direct indexing of scan_table for(;;) { UPDATE_CACHE(re, &s->gb); GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0); if (run == 66) { if (level){ CLOSE_READER(re, &s->gb); av_log(s->avctx, AV_LOG_ERROR, "illegal ac vlc code at %dx%d\n", s->mb_x, s->mb_y); return -1; } /* escape */ if (CONFIG_FLV_DECODER && s->h263_flv > 1) { int is11 = SHOW_UBITS(re, &s->gb, 1); SKIP_CACHE(re, &s->gb, 1); run = SHOW_UBITS(re, &s->gb, 7) + 1; if (is11) { SKIP_COUNTER(re, &s->gb, 1 + 7); UPDATE_CACHE(re, &s->gb); level = SHOW_SBITS(re, &s->gb, 11); SKIP_COUNTER(re, &s->gb, 11); } else { SKIP_CACHE(re, &s->gb, 7); level = SHOW_SBITS(re, &s->gb, 7); SKIP_COUNTER(re, &s->gb, 1 + 7 + 7); } } else { run = SHOW_UBITS(re, &s->gb, 7) + 1; SKIP_CACHE(re, &s->gb, 7); level = (int8_t)SHOW_UBITS(re, &s->gb, 8); SKIP_COUNTER(re, &s->gb, 7 + 8); if(level == -128){ UPDATE_CACHE(re, &s->gb); if (s->codec_id == AV_CODEC_ID_RV10) { /* XXX: should patch encoder too */ level = SHOW_SBITS(re, &s->gb, 12); SKIP_COUNTER(re, &s->gb, 12); }else{ level = SHOW_UBITS(re, &s->gb, 5); SKIP_CACHE(re, &s->gb, 5); level |= SHOW_SBITS(re, &s->gb, 6)<<5; SKIP_COUNTER(re, &s->gb, 5 + 6); } } } } else { if (SHOW_UBITS(re, &s->gb, 1)) level = -level; SKIP_COUNTER(re, &s->gb, 1); } i += run; if (i >= 64){ CLOSE_READER(re, &s->gb); // redo update without last flag, revert -1 offset i = i - run + ((run-1)&63) + 1; if (i < 64) { // only last marker, no overrun block[scan_table[i]] = level; break; } if(s->alt_inter_vlc && rl == &ff_h263_rl_inter && !s->mb_intra){ //Looks like a hack but no, it's the way it is supposed to work ... rl = &ff_rl_intra_aic; i = 0; s->gb= gb; s->bdsp.clear_block(block); goto retry; } av_log(s->avctx, AV_LOG_ERROR, "run overflow at %dx%d i:%d\n", s->mb_x, s->mb_y, s->mb_intra); return -1; } j = scan_table[i]; block[j] = level; } } not_coded: if (s->mb_intra && s->h263_aic) { ff_h263_pred_acdc(s, block, n); i = 63; } s->block_last_index[n] = i; return 0; } static int h263_skip_b_part(MpegEncContext *s, int cbp) { LOCAL_ALIGNED_16(int16_t, dblock, [64]); int i, mbi; int bli[6]; /* we have to set s->mb_intra to zero to decode B-part of PB-frame correctly * but real value should be restored in order to be used later (in OBMC condition) */ mbi = s->mb_intra; memcpy(bli, s->block_last_index, sizeof(bli)); s->mb_intra = 0; for (i = 0; i < 6; i++) { if (h263_decode_block(s, dblock, i, cbp&32) < 0) return -1; cbp+=cbp; } s->mb_intra = mbi; memcpy(s->block_last_index, bli, sizeof(bli)); return 0; } static int h263_get_modb(GetBitContext *gb, int pb_frame, int *cbpb) { int c, mv = 1; if (pb_frame < 3) { // h.263 Annex G and i263 PB-frame c = get_bits1(gb); if (pb_frame == 2 && c) mv = !get_bits1(gb); } else { // h.263 Annex M improved PB-frame mv = get_unary(gb, 0, 4) + 1; c = mv & 1; mv = !!(mv & 2); } if(c) *cbpb = get_bits(gb, 6); return mv; } int ff_h263_decode_mb(MpegEncContext *s, int16_t block[6][64]) { int cbpc, cbpy, i, cbp, pred_x, pred_y, mx, my, dquant; int16_t *mot_val; const int xy= s->mb_x + s->mb_y * s->mb_stride; int cbpb = 0, pb_mv_count = 0; av_assert2(!s->h263_pred); if (s->pict_type == AV_PICTURE_TYPE_P) { do{ if (get_bits1(&s->gb)) { /* skip mb */ s->mb_intra = 0; for(i=0;i<6;i++) s->block_last_index[i] = -1; s->mv_dir = MV_DIR_FORWARD; s->mv_type = MV_TYPE_16X16; s->current_picture.mb_type[xy] = MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_L0; s->mv[0][0][0] = 0; s->mv[0][0][1] = 0; s->mb_skipped = !(s->obmc | s->loop_filter); goto end; } cbpc = get_vlc2(&s->gb, ff_h263_inter_MCBPC_vlc.table, INTER_MCBPC_VLC_BITS, 2); if (cbpc < 0){ av_log(s->avctx, AV_LOG_ERROR, "cbpc damaged at %d %d\n", s->mb_x, s->mb_y); return -1; } }while(cbpc == 20); s->bdsp.clear_blocks(s->block[0]); dquant = cbpc & 8; s->mb_intra = ((cbpc & 4) != 0); if (s->mb_intra) goto intra; if(s->pb_frame && get_bits1(&s->gb)) pb_mv_count = h263_get_modb(&s->gb, s->pb_frame, &cbpb); cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1); if(s->alt_inter_vlc==0 || (cbpc & 3)!=3) cbpy ^= 0xF; cbp = (cbpc & 3) | (cbpy << 2); if (dquant) { h263_decode_dquant(s); } s->mv_dir = MV_DIR_FORWARD; if ((cbpc & 16) == 0) { s->current_picture.mb_type[xy] = MB_TYPE_16x16 | MB_TYPE_L0; /* 16x16 motion prediction */ s->mv_type = MV_TYPE_16X16; ff_h263_pred_motion(s, 0, 0, &pred_x, &pred_y); if (s->umvplus) mx = h263p_decode_umotion(s, pred_x); else mx = ff_h263_decode_motion(s, pred_x, 1); if (mx >= 0xffff) return -1; if (s->umvplus) my = h263p_decode_umotion(s, pred_y); else my = ff_h263_decode_motion(s, pred_y, 1); if (my >= 0xffff) return -1; s->mv[0][0][0] = mx; s->mv[0][0][1] = my; if (s->umvplus && (mx - pred_x) == 1 && (my - pred_y) == 1) skip_bits1(&s->gb); /* Bit stuffing to prevent PSC */ } else { s->current_picture.mb_type[xy] = MB_TYPE_8x8 | MB_TYPE_L0; s->mv_type = MV_TYPE_8X8; for(i=0;i<4;i++) { mot_val = ff_h263_pred_motion(s, i, 0, &pred_x, &pred_y); if (s->umvplus) mx = h263p_decode_umotion(s, pred_x); else mx = ff_h263_decode_motion(s, pred_x, 1); if (mx >= 0xffff) return -1; if (s->umvplus) my = h263p_decode_umotion(s, pred_y); else my = ff_h263_decode_motion(s, pred_y, 1); if (my >= 0xffff) return -1; s->mv[0][i][0] = mx; s->mv[0][i][1] = my; if (s->umvplus && (mx - pred_x) == 1 && (my - pred_y) == 1) skip_bits1(&s->gb); /* Bit stuffing to prevent PSC */ mot_val[0] = mx; mot_val[1] = my; } } } else if(s->pict_type==AV_PICTURE_TYPE_B) { int mb_type; const int stride= s->b8_stride; int16_t *mot_val0 = s->current_picture.motion_val[0][2 * (s->mb_x + s->mb_y * stride)]; int16_t *mot_val1 = s->current_picture.motion_val[1][2 * (s->mb_x + s->mb_y * stride)]; // const int mv_xy= s->mb_x + 1 + s->mb_y * s->mb_stride; //FIXME ugly mot_val0[0 ]= mot_val0[2 ]= mot_val0[0+2*stride]= mot_val0[2+2*stride]= mot_val0[1 ]= mot_val0[3 ]= mot_val0[1+2*stride]= mot_val0[3+2*stride]= mot_val1[0 ]= mot_val1[2 ]= mot_val1[0+2*stride]= mot_val1[2+2*stride]= mot_val1[1 ]= mot_val1[3 ]= mot_val1[1+2*stride]= mot_val1[3+2*stride]= 0; do{ mb_type= get_vlc2(&s->gb, h263_mbtype_b_vlc.table, H263_MBTYPE_B_VLC_BITS, 2); if (mb_type < 0){ av_log(s->avctx, AV_LOG_ERROR, "b mb_type damaged at %d %d\n", s->mb_x, s->mb_y); return -1; } mb_type= h263_mb_type_b_map[ mb_type ]; }while(!mb_type); s->mb_intra = IS_INTRA(mb_type); if(HAS_CBP(mb_type)){ s->bdsp.clear_blocks(s->block[0]); cbpc = get_vlc2(&s->gb, cbpc_b_vlc.table, CBPC_B_VLC_BITS, 1); if(s->mb_intra){ dquant = IS_QUANT(mb_type); goto intra; } cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1); if (cbpy < 0){ av_log(s->avctx, AV_LOG_ERROR, "b cbpy damaged at %d %d\n", s->mb_x, s->mb_y); return -1; } if(s->alt_inter_vlc==0 || (cbpc & 3)!=3) cbpy ^= 0xF; cbp = (cbpc & 3) | (cbpy << 2); }else cbp=0; av_assert2(!s->mb_intra); if(IS_QUANT(mb_type)){ h263_decode_dquant(s); } if(IS_DIRECT(mb_type)){ s->mv_dir = MV_DIR_FORWARD | MV_DIR_BACKWARD | MV_DIRECT; mb_type |= ff_mpeg4_set_direct_mv(s, 0, 0); }else{ s->mv_dir = 0; s->mv_type= MV_TYPE_16X16; //FIXME UMV if(USES_LIST(mb_type, 0)){ int16_t *mot_val= ff_h263_pred_motion(s, 0, 0, &mx, &my); s->mv_dir = MV_DIR_FORWARD; mx = ff_h263_decode_motion(s, mx, 1); my = ff_h263_decode_motion(s, my, 1); s->mv[0][0][0] = mx; s->mv[0][0][1] = my; mot_val[0 ]= mot_val[2 ]= mot_val[0+2*stride]= mot_val[2+2*stride]= mx; mot_val[1 ]= mot_val[3 ]= mot_val[1+2*stride]= mot_val[3+2*stride]= my; } if(USES_LIST(mb_type, 1)){ int16_t *mot_val= ff_h263_pred_motion(s, 0, 1, &mx, &my); s->mv_dir |= MV_DIR_BACKWARD; mx = ff_h263_decode_motion(s, mx, 1); my = ff_h263_decode_motion(s, my, 1); s->mv[1][0][0] = mx; s->mv[1][0][1] = my; mot_val[0 ]= mot_val[2 ]= mot_val[0+2*stride]= mot_val[2+2*stride]= mx; mot_val[1 ]= mot_val[3 ]= mot_val[1+2*stride]= mot_val[3+2*stride]= my; } } s->current_picture.mb_type[xy] = mb_type; } else { /* I-Frame */ do{ cbpc = get_vlc2(&s->gb, ff_h263_intra_MCBPC_vlc.table, INTRA_MCBPC_VLC_BITS, 2); if (cbpc < 0){ av_log(s->avctx, AV_LOG_ERROR, "I cbpc damaged at %d %d\n", s->mb_x, s->mb_y); return -1; } }while(cbpc == 8); s->bdsp.clear_blocks(s->block[0]); dquant = cbpc & 4; s->mb_intra = 1; intra: s->current_picture.mb_type[xy] = MB_TYPE_INTRA; if (s->h263_aic) { s->ac_pred = get_bits1(&s->gb); if(s->ac_pred){ s->current_picture.mb_type[xy] = MB_TYPE_INTRA | MB_TYPE_ACPRED; s->h263_aic_dir = get_bits1(&s->gb); } }else s->ac_pred = 0; if(s->pb_frame && get_bits1(&s->gb)) pb_mv_count = h263_get_modb(&s->gb, s->pb_frame, &cbpb); cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1); if(cbpy<0){ av_log(s->avctx, AV_LOG_ERROR, "I cbpy damaged at %d %d\n", s->mb_x, s->mb_y); return -1; } cbp = (cbpc & 3) | (cbpy << 2); if (dquant) { h263_decode_dquant(s); } pb_mv_count += !!s->pb_frame; } while(pb_mv_count--){ ff_h263_decode_motion(s, 0, 1); ff_h263_decode_motion(s, 0, 1); } /* decode each block */ for (i = 0; i < 6; i++) { if (h263_decode_block(s, block[i], i, cbp&32) < 0) return -1; cbp+=cbp; } if(s->pb_frame && h263_skip_b_part(s, cbpb) < 0) return -1; if(s->obmc && !s->mb_intra){ if(s->pict_type == AV_PICTURE_TYPE_P && s->mb_x+1<s->mb_width && s->mb_num_left != 1) preview_obmc(s); } end: /* per-MB end of slice check */ { int v= show_bits(&s->gb, 16); if (get_bits_left(&s->gb) < 16) { v >>= 16 - get_bits_left(&s->gb); } if(v==0) return SLICE_END; } return SLICE_OK; } /* most is hardcoded. should extend to handle all h263 streams */ int ff_h263_decode_picture_header(MpegEncContext *s) { int format, width, height, i, ret; uint32_t startcode; align_get_bits(&s->gb); if (show_bits(&s->gb, 2) == 2 && s->avctx->frame_number == 0) { av_log(s->avctx, AV_LOG_WARNING, "Header looks like RTP instead of H.263\n"); } startcode= get_bits(&s->gb, 22-8); for(i= get_bits_left(&s->gb); i>24; i-=8) { startcode = ((startcode << 8) | get_bits(&s->gb, 8)) & 0x003FFFFF; if(startcode == 0x20) break; } if (startcode != 0x20) { av_log(s->avctx, AV_LOG_ERROR, "Bad picture start code\n"); return -1; } /* temporal reference */ i = get_bits(&s->gb, 8); /* picture timestamp */ if( (s->picture_number&~0xFF)+i < s->picture_number) i+= 256; s->picture_number= (s->picture_number&~0xFF) + i; /* PTYPE starts here */ if (check_marker(&s->gb, "in PTYPE") != 1) { return -1; } if (get_bits1(&s->gb) != 0) { av_log(s->avctx, AV_LOG_ERROR, "Bad H263 id\n"); return -1; /* h263 id */ } skip_bits1(&s->gb); /* split screen off */ skip_bits1(&s->gb); /* camera off */ skip_bits1(&s->gb); /* freeze picture release off */ format = get_bits(&s->gb, 3); /* 0 forbidden 1 sub-QCIF 10 QCIF 7 extended PTYPE (PLUSPTYPE) */ if (format != 7 && format != 6) { s->h263_plus = 0; /* H.263v1 */ width = ff_h263_format[format][0]; height = ff_h263_format[format][1]; if (!width) return -1; s->pict_type = AV_PICTURE_TYPE_I + get_bits1(&s->gb); s->h263_long_vectors = get_bits1(&s->gb); if (get_bits1(&s->gb) != 0) { av_log(s->avctx, AV_LOG_ERROR, "H263 SAC not supported\n"); return -1; /* SAC: off */ } s->obmc= get_bits1(&s->gb); /* Advanced prediction mode */ s->unrestricted_mv = s->h263_long_vectors || s->obmc; s->pb_frame = get_bits1(&s->gb); s->chroma_qscale= s->qscale = get_bits(&s->gb, 5); skip_bits1(&s->gb); /* Continuous Presence Multipoint mode: off */ s->width = width; s->height = height; s->avctx->sample_aspect_ratio= (AVRational){12,11}; s->avctx->framerate = (AVRational){ 30000, 1001 }; } else { int ufep; /* H.263v2 */ s->h263_plus = 1; ufep = get_bits(&s->gb, 3); /* Update Full Extended PTYPE */ /* ufep other than 0 and 1 are reserved */ if (ufep == 1) { /* OPPTYPE */ format = get_bits(&s->gb, 3); ff_dlog(s->avctx, "ufep=1, format: %d\n", format); s->custom_pcf= get_bits1(&s->gb); s->umvplus = get_bits1(&s->gb); /* Unrestricted Motion Vector */ if (get_bits1(&s->gb) != 0) { av_log(s->avctx, AV_LOG_ERROR, "Syntax-based Arithmetic Coding (SAC) not supported\n"); } s->obmc= get_bits1(&s->gb); /* Advanced prediction mode */ s->h263_aic = get_bits1(&s->gb); /* Advanced Intra Coding (AIC) */ s->loop_filter= get_bits1(&s->gb); s->unrestricted_mv = s->umvplus || s->obmc || s->loop_filter; if(s->avctx->lowres) s->loop_filter = 0; s->h263_slice_structured= get_bits1(&s->gb); if (get_bits1(&s->gb) != 0) { av_log(s->avctx, AV_LOG_ERROR, "Reference Picture Selection not supported\n"); } if (get_bits1(&s->gb) != 0) { av_log(s->avctx, AV_LOG_ERROR, "Independent Segment Decoding not supported\n"); } s->alt_inter_vlc= get_bits1(&s->gb); s->modified_quant= get_bits1(&s->gb); if(s->modified_quant) s->chroma_qscale_table= ff_h263_chroma_qscale_table; skip_bits(&s->gb, 1); /* Prevent start code emulation */ skip_bits(&s->gb, 3); /* Reserved */ } else if (ufep != 0) { av_log(s->avctx, AV_LOG_ERROR, "Bad UFEP type (%d)\n", ufep); return -1; } /* MPPTYPE */ s->pict_type = get_bits(&s->gb, 3); switch(s->pict_type){ case 0: s->pict_type= AV_PICTURE_TYPE_I;break; case 1: s->pict_type= AV_PICTURE_TYPE_P;break; case 2: s->pict_type= AV_PICTURE_TYPE_P;s->pb_frame = 3;break; case 3: s->pict_type= AV_PICTURE_TYPE_B;break; case 7: s->pict_type= AV_PICTURE_TYPE_I;break; //ZYGO default: return -1; } skip_bits(&s->gb, 2); s->no_rounding = get_bits1(&s->gb); skip_bits(&s->gb, 4); /* Get the picture dimensions */ if (ufep) { if (format == 6) { /* Custom Picture Format (CPFMT) */ s->aspect_ratio_info = get_bits(&s->gb, 4); ff_dlog(s->avctx, "aspect: %d\n", s->aspect_ratio_info); /* aspect ratios: 0 - forbidden 1 - 1:1 2 - 12:11 (CIF 4:3) 3 - 10:11 (525-type 4:3) 4 - 16:11 (CIF 16:9) 5 - 40:33 (525-type 16:9) 6-14 - reserved */ width = (get_bits(&s->gb, 9) + 1) * 4; check_marker(&s->gb, "in dimensions"); height = get_bits(&s->gb, 9) * 4; ff_dlog(s->avctx, "\nH.263+ Custom picture: %dx%d\n",width,height); if (s->aspect_ratio_info == FF_ASPECT_EXTENDED) { /* aspected dimensions */ s->avctx->sample_aspect_ratio.num= get_bits(&s->gb, 8); s->avctx->sample_aspect_ratio.den= get_bits(&s->gb, 8); }else{ s->avctx->sample_aspect_ratio= ff_h263_pixel_aspect[s->aspect_ratio_info]; } } else { width = ff_h263_format[format][0]; height = ff_h263_format[format][1]; s->avctx->sample_aspect_ratio= (AVRational){12,11}; } s->avctx->sample_aspect_ratio.den <<= s->ehc_mode; if ((width == 0) || (height == 0)) return -1; s->width = width; s->height = height; if(s->custom_pcf){ int gcd; s->avctx->framerate.num = 1800000; s->avctx->framerate.den = 1000 + get_bits1(&s->gb); s->avctx->framerate.den *= get_bits(&s->gb, 7); if(s->avctx->framerate.den == 0){ av_log(s, AV_LOG_ERROR, "zero framerate\n"); return -1; } gcd= av_gcd(s->avctx->framerate.den, s->avctx->framerate.num); s->avctx->framerate.den /= gcd; s->avctx->framerate.num /= gcd; }else{ s->avctx->framerate = (AVRational){ 30000, 1001 }; } } if(s->custom_pcf){ skip_bits(&s->gb, 2); //extended Temporal reference } if (ufep) { if (s->umvplus) { if(get_bits1(&s->gb)==0) /* Unlimited Unrestricted Motion Vectors Indicator (UUI) */ skip_bits1(&s->gb); } if(s->h263_slice_structured){ if (get_bits1(&s->gb) != 0) { av_log(s->avctx, AV_LOG_ERROR, "rectangular slices not supported\n"); } if (get_bits1(&s->gb) != 0) { av_log(s->avctx, AV_LOG_ERROR, "unordered slices not supported\n"); } } } s->qscale = get_bits(&s->gb, 5); } if ((ret = av_image_check_size(s->width, s->height, 0, s)) < 0) return ret; s->mb_width = (s->width + 15) / 16; s->mb_height = (s->height + 15) / 16; s->mb_num = s->mb_width * s->mb_height; if (s->pb_frame) { skip_bits(&s->gb, 3); /* Temporal reference for B-pictures */ if (s->custom_pcf) skip_bits(&s->gb, 2); //extended Temporal reference skip_bits(&s->gb, 2); /* Quantization information for B-pictures */ } if (s->pict_type!=AV_PICTURE_TYPE_B) { s->time = s->picture_number; s->pp_time = s->time - s->last_non_b_time; s->last_non_b_time = s->time; }else{ s->time = s->picture_number; s->pb_time = s->pp_time - (s->last_non_b_time - s->time); if (s->pp_time <=s->pb_time || s->pp_time <= s->pp_time - s->pb_time || s->pp_time <= 0){ s->pp_time = 2; s->pb_time = 1; } ff_mpeg4_init_direct_mv(s); } /* PEI */ if (skip_1stop_8data_bits(&s->gb) < 0) return AVERROR_INVALIDDATA; if(s->h263_slice_structured){ if (check_marker(&s->gb, "SEPB1") != 1) { return -1; } ff_h263_decode_mba(s); if (check_marker(&s->gb, "SEPB2") != 1) { return -1; } } s->f_code = 1; if(s->h263_aic){ s->y_dc_scale_table= s->c_dc_scale_table= ff_aic_dc_scale_table; }else{ s->y_dc_scale_table= s->c_dc_scale_table= ff_mpeg1_dc_scale_table; } ff_h263_show_pict_info(s); if (s->pict_type == AV_PICTURE_TYPE_I && s->codec_tag == AV_RL32("ZYGO") && get_bits_left(&s->gb) >= 85 + 13*3*16 + 50){ int i,j; for(i=0; i<85; i++) av_log(s->avctx, AV_LOG_DEBUG, "%d", get_bits1(&s->gb)); av_log(s->avctx, AV_LOG_DEBUG, "\n"); for(i=0; i<13; i++){ for(j=0; j<3; j++){ int v= get_bits(&s->gb, 8); v |= get_sbits(&s->gb, 8)<<8; av_log(s->avctx, AV_LOG_DEBUG, " %5d", v); } av_log(s->avctx, AV_LOG_DEBUG, "\n"); } for(i=0; i<50; i++) av_log(s->avctx, AV_LOG_DEBUG, "%d", get_bits1(&s->gb)); } return 0; }