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1131 lines
36 KiB
1131 lines
36 KiB
/* |
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* ITU H263 bitstream decoder |
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* Copyright (c) 2000,2001 Fabrice Bellard |
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* H263+ support. |
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* Copyright (c) 2001 Juan J. Sierralta P |
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* Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at> |
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* |
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* This file is part of FFmpeg. |
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* |
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* FFmpeg is free software; you can redistribute it and/or |
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* modify it under the terms of the GNU Lesser General Public |
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* License as published by the Free Software Foundation; either |
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* version 2.1 of the License, or (at your option) any later version. |
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* |
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* FFmpeg is distributed in the hope that it will be useful, |
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* but WITHOUT ANY WARRANTY; without even the implied warranty of |
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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* Lesser General Public License for more details. |
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* |
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* You should have received a copy of the GNU Lesser General Public |
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* License along with FFmpeg; if not, write to the Free Software |
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
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*/ |
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|
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/** |
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* @file libavcodec/ituh263dec.c |
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* h263 decoder. |
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*/ |
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|
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//#define DEBUG |
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#include <limits.h> |
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|
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#include "dsputil.h" |
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#include "avcodec.h" |
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#include "mpegvideo.h" |
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#include "h263.h" |
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#include "mathops.h" |
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#include "unary.h" |
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#include "flv.h" |
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#include "mpeg4video.h" |
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|
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//#undef NDEBUG |
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//#include <assert.h> |
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|
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// The defines below define the number of bits that are read at once for |
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// reading vlc values. Changing these may improve speed and data cache needs |
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// be aware though that decreasing them may need the number of stages that is |
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// passed to get_vlc* to be increased. |
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#define MV_VLC_BITS 9 |
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#define H263_MBTYPE_B_VLC_BITS 6 |
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#define CBPC_B_VLC_BITS 3 |
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|
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static const int h263_mb_type_b_map[15]= { |
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MB_TYPE_DIRECT2 | MB_TYPE_L0L1, |
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MB_TYPE_DIRECT2 | MB_TYPE_L0L1 | MB_TYPE_CBP, |
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MB_TYPE_DIRECT2 | MB_TYPE_L0L1 | MB_TYPE_CBP | MB_TYPE_QUANT, |
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MB_TYPE_L0 | MB_TYPE_16x16, |
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MB_TYPE_L0 | MB_TYPE_CBP | MB_TYPE_16x16, |
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MB_TYPE_L0 | MB_TYPE_CBP | MB_TYPE_QUANT | MB_TYPE_16x16, |
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MB_TYPE_L1 | MB_TYPE_16x16, |
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MB_TYPE_L1 | MB_TYPE_CBP | MB_TYPE_16x16, |
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MB_TYPE_L1 | MB_TYPE_CBP | MB_TYPE_QUANT | MB_TYPE_16x16, |
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MB_TYPE_L0L1 | MB_TYPE_16x16, |
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MB_TYPE_L0L1 | MB_TYPE_CBP | MB_TYPE_16x16, |
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MB_TYPE_L0L1 | MB_TYPE_CBP | MB_TYPE_QUANT | MB_TYPE_16x16, |
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0, //stuffing |
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MB_TYPE_INTRA4x4 | MB_TYPE_CBP, |
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MB_TYPE_INTRA4x4 | MB_TYPE_CBP | MB_TYPE_QUANT, |
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}; |
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|
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void ff_h263_show_pict_info(MpegEncContext *s){ |
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if(s->avctx->debug&FF_DEBUG_PICT_INFO){ |
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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", |
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s->qscale, av_get_pict_type_char(s->pict_type), |
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s->gb.size_in_bits, 1-s->no_rounding, |
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s->obmc ? " AP" : "", |
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s->umvplus ? " UMV" : "", |
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s->h263_long_vectors ? " LONG" : "", |
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s->h263_plus ? " +" : "", |
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s->h263_aic ? " AIC" : "", |
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s->alt_inter_vlc ? " AIV" : "", |
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s->modified_quant ? " MQ" : "", |
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s->loop_filter ? " LOOP" : "", |
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s->h263_slice_structured ? " SS" : "", |
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s->avctx->time_base.den, s->avctx->time_base.num |
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); |
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} |
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} |
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|
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/***********************************************/ |
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/* decoding */ |
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|
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VLC ff_h263_intra_MCBPC_vlc; |
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VLC ff_h263_inter_MCBPC_vlc; |
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VLC ff_h263_cbpy_vlc; |
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static VLC mv_vlc; |
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static VLC h263_mbtype_b_vlc; |
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static VLC cbpc_b_vlc; |
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|
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/* init vlcs */ |
|
|
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/* XXX: find a better solution to handle static init */ |
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void h263_decode_init_vlc(MpegEncContext *s) |
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{ |
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static int done = 0; |
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|
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if (!done) { |
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done = 1; |
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|
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INIT_VLC_STATIC(&ff_h263_intra_MCBPC_vlc, INTRA_MCBPC_VLC_BITS, 9, |
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ff_h263_intra_MCBPC_bits, 1, 1, |
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ff_h263_intra_MCBPC_code, 1, 1, 72); |
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INIT_VLC_STATIC(&ff_h263_inter_MCBPC_vlc, INTER_MCBPC_VLC_BITS, 28, |
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ff_h263_inter_MCBPC_bits, 1, 1, |
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ff_h263_inter_MCBPC_code, 1, 1, 198); |
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INIT_VLC_STATIC(&ff_h263_cbpy_vlc, CBPY_VLC_BITS, 16, |
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&ff_h263_cbpy_tab[0][1], 2, 1, |
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&ff_h263_cbpy_tab[0][0], 2, 1, 64); |
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INIT_VLC_STATIC(&mv_vlc, MV_VLC_BITS, 33, |
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&mvtab[0][1], 2, 1, |
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&mvtab[0][0], 2, 1, 538); |
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init_rl(&ff_h263_rl_inter, ff_h263_static_rl_table_store[0]); |
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init_rl(&rl_intra_aic, ff_h263_static_rl_table_store[1]); |
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INIT_VLC_RL(ff_h263_rl_inter, 554); |
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INIT_VLC_RL(rl_intra_aic, 554); |
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INIT_VLC_STATIC(&h263_mbtype_b_vlc, H263_MBTYPE_B_VLC_BITS, 15, |
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&h263_mbtype_b_tab[0][1], 2, 1, |
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&h263_mbtype_b_tab[0][0], 2, 1, 80); |
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INIT_VLC_STATIC(&cbpc_b_vlc, CBPC_B_VLC_BITS, 4, |
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&cbpc_b_tab[0][1], 2, 1, |
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&cbpc_b_tab[0][0], 2, 1, 8); |
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} |
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} |
|
|
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int ff_h263_decode_mba(MpegEncContext *s) |
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{ |
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int i, mb_pos; |
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|
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for(i=0; i<6; i++){ |
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if(s->mb_num-1 <= ff_mba_max[i]) break; |
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} |
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mb_pos= get_bits(&s->gb, ff_mba_length[i]); |
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s->mb_x= mb_pos % s->mb_width; |
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s->mb_y= mb_pos / s->mb_width; |
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|
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return mb_pos; |
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} |
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|
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/** |
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* decodes the group of blocks header or slice header. |
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* @return <0 if an error occurred |
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*/ |
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static int h263_decode_gob_header(MpegEncContext *s) |
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{ |
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unsigned int val, gfid, gob_number; |
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int left; |
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|
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/* Check for GOB Start Code */ |
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val = show_bits(&s->gb, 16); |
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if(val) |
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return -1; |
|
|
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/* We have a GBSC probably with GSTUFF */ |
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skip_bits(&s->gb, 16); /* Drop the zeros */ |
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left= get_bits_left(&s->gb); |
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//MN: we must check the bits left or we might end in a infinite loop (or segfault) |
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for(;left>13; left--){ |
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if(get_bits1(&s->gb)) break; /* Seek the '1' bit */ |
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} |
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if(left<=13) |
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return -1; |
|
|
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if(s->h263_slice_structured){ |
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if(get_bits1(&s->gb)==0) |
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return -1; |
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|
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ff_h263_decode_mba(s); |
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|
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if(s->mb_num > 1583) |
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if(get_bits1(&s->gb)==0) |
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return -1; |
|
|
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s->qscale = get_bits(&s->gb, 5); /* SQUANT */ |
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if(get_bits1(&s->gb)==0) |
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return -1; |
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gfid = get_bits(&s->gb, 2); /* GFID */ |
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}else{ |
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gob_number = get_bits(&s->gb, 5); /* GN */ |
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s->mb_x= 0; |
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s->mb_y= s->gob_index* gob_number; |
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gfid = get_bits(&s->gb, 2); /* GFID */ |
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s->qscale = get_bits(&s->gb, 5); /* GQUANT */ |
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} |
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|
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if(s->mb_y >= s->mb_height) |
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return -1; |
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|
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if(s->qscale==0) |
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return -1; |
|
|
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return 0; |
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} |
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|
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/** |
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* finds the next resync_marker |
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* @param p pointer to buffer to scan |
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* @param end pointer to the end of the buffer |
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* @return pointer to the next resync_marker, or end if none was found |
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*/ |
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const uint8_t *ff_h263_find_resync_marker(const uint8_t *restrict p, const uint8_t * restrict end) |
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{ |
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assert(p < end); |
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|
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end-=2; |
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p++; |
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for(;p<end; p+=2){ |
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if(!*p){ |
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if (!p[-1] && p[1]) return p - 1; |
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else if(!p[ 1] && p[2]) return p; |
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} |
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} |
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return end+2; |
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} |
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|
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/** |
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* decodes the group of blocks / video packet header. |
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* @return bit position of the resync_marker, or <0 if none was found |
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*/ |
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int ff_h263_resync(MpegEncContext *s){ |
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int left, pos, ret; |
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|
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if(s->codec_id==CODEC_ID_MPEG4){ |
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skip_bits1(&s->gb); |
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align_get_bits(&s->gb); |
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} |
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|
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if(show_bits(&s->gb, 16)==0){ |
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pos= get_bits_count(&s->gb); |
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if(CONFIG_MPEG4_DECODER && s->codec_id==CODEC_ID_MPEG4) |
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ret= mpeg4_decode_video_packet_header(s); |
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else |
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ret= h263_decode_gob_header(s); |
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if(ret>=0) |
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return pos; |
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} |
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//OK, it's not where it is supposed to be ... |
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s->gb= s->last_resync_gb; |
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align_get_bits(&s->gb); |
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left= get_bits_left(&s->gb); |
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|
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for(;left>16+1+5+5; left-=8){ |
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if(show_bits(&s->gb, 16)==0){ |
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GetBitContext bak= s->gb; |
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|
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pos= get_bits_count(&s->gb); |
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if(CONFIG_MPEG4_DECODER && s->codec_id==CODEC_ID_MPEG4) |
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ret= mpeg4_decode_video_packet_header(s); |
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else |
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ret= h263_decode_gob_header(s); |
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if(ret>=0) |
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return pos; |
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|
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s->gb= bak; |
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} |
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skip_bits(&s->gb, 8); |
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} |
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|
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return -1; |
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} |
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|
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int h263_decode_motion(MpegEncContext * s, int pred, int f_code) |
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{ |
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int code, val, sign, shift, l; |
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code = get_vlc2(&s->gb, mv_vlc.table, MV_VLC_BITS, 2); |
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|
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if (code == 0) |
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return pred; |
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if (code < 0) |
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return 0xffff; |
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|
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sign = get_bits1(&s->gb); |
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shift = f_code - 1; |
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val = code; |
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if (shift) { |
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val = (val - 1) << shift; |
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val |= get_bits(&s->gb, shift); |
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val++; |
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} |
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if (sign) |
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val = -val; |
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val += pred; |
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|
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/* modulo decoding */ |
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if (!s->h263_long_vectors) { |
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l = INT_BIT - 5 - f_code; |
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val = (val<<l)>>l; |
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} else { |
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/* horrible h263 long vector mode */ |
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if (pred < -31 && val < -63) |
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val += 64; |
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if (pred > 32 && val > 63) |
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val -= 64; |
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|
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} |
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return val; |
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} |
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|
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|
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/* Decodes RVLC of H.263+ UMV */ |
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static int h263p_decode_umotion(MpegEncContext * s, int pred) |
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{ |
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int code = 0, sign; |
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|
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if (get_bits1(&s->gb)) /* Motion difference = 0 */ |
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return pred; |
|
|
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code = 2 + get_bits1(&s->gb); |
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|
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while (get_bits1(&s->gb)) |
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{ |
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code <<= 1; |
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code += get_bits1(&s->gb); |
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} |
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sign = code & 1; |
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code >>= 1; |
|
|
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code = (sign) ? (pred - code) : (pred + code); |
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dprintf(s->avctx,"H.263+ UMV Motion = %d\n", code); |
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return code; |
|
|
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} |
|
|
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/** |
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* read the next MVs for OBMC. yes this is a ugly hack, feel free to send a patch :) |
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*/ |
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static void preview_obmc(MpegEncContext *s){ |
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GetBitContext gb= s->gb; |
|
|
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int cbpc, i, pred_x, pred_y, mx, my; |
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int16_t *mot_val; |
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const int xy= s->mb_x + 1 + s->mb_y * s->mb_stride; |
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const int stride= s->b8_stride*2; |
|
|
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for(i=0; i<4; i++) |
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s->block_index[i]+= 2; |
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for(i=4; i<6; i++) |
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s->block_index[i]+= 1; |
|
s->mb_x++; |
|
|
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assert(s->pict_type == FF_P_TYPE); |
|
|
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do{ |
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if (get_bits1(&s->gb)) { |
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/* skip mb */ |
|
mot_val = s->current_picture.motion_val[0][ s->block_index[0] ]; |
|
mot_val[0 ]= mot_val[2 ]= |
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mot_val[0+stride]= mot_val[2+stride]= 0; |
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mot_val[1 ]= mot_val[3 ]= |
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mot_val[1+stride]= mot_val[3+stride]= 0; |
|
|
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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{ |
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get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1); |
|
if (cbpc & 8) { |
|
if(s->modified_quant){ |
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if(get_bits1(&s->gb)) skip_bits(&s->gb, 1); |
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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= h263_pred_motion(s, 0, 0, &pred_x, &pred_y); |
|
if (s->umvplus) |
|
mx = h263p_decode_umotion(s, pred_x); |
|
else |
|
mx = h263_decode_motion(s, pred_x, 1); |
|
|
|
if (s->umvplus) |
|
my = h263p_decode_umotion(s, pred_y); |
|
else |
|
my = 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 = h263_pred_motion(s, i, 0, &pred_x, &pred_y); |
|
if (s->umvplus) |
|
mx = h263p_decode_umotion(s, pred_x); |
|
else |
|
mx = h263_decode_motion(s, pred_x, 1); |
|
|
|
if (s->umvplus) |
|
my = h263p_decode_umotion(s, pred_y); |
|
else |
|
my = 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= 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, DCTELEM * block, |
|
int n, int coded) |
|
{ |
|
int code, level, i, j, last, 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 = &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(s->codec_id == CODEC_ID_RV10){ |
|
#if CONFIG_RV10_DECODER |
|
if (s->rv10_version == 3 && s->pict_type == FF_I_TYPE) { |
|
int component, diff; |
|
component = (n <= 3 ? 0 : n - 4 + 1); |
|
level = s->last_dc[component]; |
|
if (s->rv10_first_dc_coded[component]) { |
|
diff = 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; |
|
} |
|
#endif |
|
}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->error_recognition >= FF_ER_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: |
|
for(;;) { |
|
code = get_vlc2(&s->gb, rl->vlc.table, TEX_VLC_BITS, 2); |
|
if (code < 0){ |
|
av_log(s->avctx, AV_LOG_ERROR, "illegal ac vlc code at %dx%d\n", s->mb_x, s->mb_y); |
|
return -1; |
|
} |
|
if (code == rl->n) { |
|
/* escape */ |
|
if (CONFIG_FLV_DECODER && s->h263_flv > 1) { |
|
ff_flv2_decode_ac_esc(&s->gb, &level, &run, &last); |
|
} else { |
|
last = get_bits1(&s->gb); |
|
run = get_bits(&s->gb, 6); |
|
level = (int8_t)get_bits(&s->gb, 8); |
|
if(level == -128){ |
|
if (s->codec_id == CODEC_ID_RV10) { |
|
/* XXX: should patch encoder too */ |
|
level = get_sbits(&s->gb, 12); |
|
}else{ |
|
level = get_bits(&s->gb, 5); |
|
level |= get_sbits(&s->gb, 6)<<5; |
|
} |
|
} |
|
} |
|
} else { |
|
run = rl->table_run[code]; |
|
level = rl->table_level[code]; |
|
last = code >= rl->last; |
|
if (get_bits1(&s->gb)) |
|
level = -level; |
|
} |
|
i += run; |
|
if (i >= 64){ |
|
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 = &rl_intra_aic; |
|
i = 0; |
|
s->gb= gb; |
|
s->dsp.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; |
|
if (last) |
|
break; |
|
i++; |
|
} |
|
not_coded: |
|
if (s->mb_intra && s->h263_aic) { |
|
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) |
|
{ |
|
DECLARE_ALIGNED(16, DCTELEM, dblock[64]); |
|
int i, mbi; |
|
|
|
/* 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; |
|
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; |
|
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, |
|
DCTELEM 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; |
|
|
|
assert(!s->h263_pred); |
|
|
|
if (s->pict_type == FF_P_TYPE) { |
|
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->dsp.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; |
|
h263_pred_motion(s, 0, 0, &pred_x, &pred_y); |
|
if (s->umvplus) |
|
mx = h263p_decode_umotion(s, pred_x); |
|
else |
|
mx = h263_decode_motion(s, pred_x, 1); |
|
|
|
if (mx >= 0xffff) |
|
return -1; |
|
|
|
if (s->umvplus) |
|
my = h263p_decode_umotion(s, pred_y); |
|
else |
|
my = 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 = h263_pred_motion(s, i, 0, &pred_x, &pred_y); |
|
if (s->umvplus) |
|
mx = h263p_decode_umotion(s, pred_x); |
|
else |
|
mx = h263_decode_motion(s, pred_x, 1); |
|
if (mx >= 0xffff) |
|
return -1; |
|
|
|
if (s->umvplus) |
|
my = h263p_decode_umotion(s, pred_y); |
|
else |
|
my = 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==FF_B_TYPE) { |
|
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->dsp.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; |
|
|
|
assert(!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= h263_pred_motion(s, 0, 0, &mx, &my); |
|
s->mv_dir = MV_DIR_FORWARD; |
|
|
|
mx = h263_decode_motion(s, mx, 1); |
|
my = 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= h263_pred_motion(s, 0, 1, &mx, &my); |
|
s->mv_dir |= MV_DIR_BACKWARD; |
|
|
|
mx = h263_decode_motion(s, mx, 1); |
|
my = 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->dsp.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--){ |
|
h263_decode_motion(s, 0, 1); |
|
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 == FF_P_TYPE && 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_count(&s->gb) + 16 > s->gb.size_in_bits){ |
|
v>>= get_bits_count(&s->gb) + 16 - s->gb.size_in_bits; |
|
} |
|
|
|
if(v==0) |
|
return SLICE_END; |
|
} |
|
|
|
return SLICE_OK; |
|
} |
|
|
|
/* most is hardcoded. should extend to handle all h263 streams */ |
|
int h263_decode_picture_header(MpegEncContext *s) |
|
{ |
|
int format, width, height, i; |
|
uint32_t startcode; |
|
|
|
align_get_bits(&s->gb); |
|
|
|
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->current_picture_ptr->pts= |
|
s->picture_number= (s->picture_number&~0xFF) + i; |
|
|
|
/* PTYPE starts here */ |
|
if (get_bits1(&s->gb) != 1) { |
|
/* marker */ |
|
av_log(s->avctx, AV_LOG_ERROR, "Bad marker\n"); |
|
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 = h263_format[format][0]; |
|
height = h263_format[format][1]; |
|
if (!width) |
|
return -1; |
|
|
|
s->pict_type = FF_I_TYPE + 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->time_base= (AVRational){1001, 30000}; |
|
} 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); |
|
dprintf(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; |
|
|
|
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= FF_I_TYPE;break; |
|
case 1: s->pict_type= FF_P_TYPE;break; |
|
case 2: s->pict_type= FF_P_TYPE;s->pb_frame = 3;break; |
|
case 3: s->pict_type= FF_B_TYPE;break; |
|
case 7: s->pict_type= FF_I_TYPE;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); |
|
dprintf(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; |
|
skip_bits1(&s->gb); |
|
height = get_bits(&s->gb, 9) * 4; |
|
dprintf(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 = h263_format[format][0]; |
|
height = h263_format[format][1]; |
|
s->avctx->sample_aspect_ratio= (AVRational){12,11}; |
|
} |
|
if ((width == 0) || (height == 0)) |
|
return -1; |
|
s->width = width; |
|
s->height = height; |
|
|
|
if(s->custom_pcf){ |
|
int gcd; |
|
s->avctx->time_base.den= 1800000; |
|
s->avctx->time_base.num= 1000 + get_bits1(&s->gb); |
|
s->avctx->time_base.num*= get_bits(&s->gb, 7); |
|
if(s->avctx->time_base.num == 0){ |
|
av_log(s, AV_LOG_ERROR, "zero framerate\n"); |
|
return -1; |
|
} |
|
gcd= av_gcd(s->avctx->time_base.den, s->avctx->time_base.num); |
|
s->avctx->time_base.den /= gcd; |
|
s->avctx->time_base.num /= gcd; |
|
}else{ |
|
s->avctx->time_base= (AVRational){1001, 30000}; |
|
} |
|
} |
|
|
|
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); |
|
} |
|
|
|
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 */ |
|
} |
|
|
|
/* PEI */ |
|
while (get_bits1(&s->gb) != 0) { |
|
skip_bits(&s->gb, 8); |
|
} |
|
|
|
if(s->h263_slice_structured){ |
|
if (get_bits1(&s->gb) != 1) { |
|
av_log(s->avctx, AV_LOG_ERROR, "SEPB1 marker missing\n"); |
|
return -1; |
|
} |
|
|
|
ff_h263_decode_mba(s); |
|
|
|
if (get_bits1(&s->gb) != 1) { |
|
av_log(s->avctx, AV_LOG_ERROR, "SEPB2 marker missing\n"); |
|
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 == FF_I_TYPE && s->codec_tag == AV_RL32("ZYGO")){ |
|
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; |
|
}
|
|
|