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| Rev | Author | Line No. | Line |
|---|---|---|---|
| 4349 | Serge | 1 | /* |
| 2 | * RAW H.261 video demuxer |
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| 3 | * Copyright (c) 2009 Michael Niedermayer |
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| 4 | * |
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| 5 | * This file is part of FFmpeg. |
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| 6 | * |
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| 7 | * FFmpeg is free software; you can redistribute it and/or |
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| 8 | * modify it under the terms of the GNU Lesser General Public |
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| 9 | * License as published by the Free Software Foundation; either |
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| 10 | * version 2.1 of the License, or (at your option) any later version. |
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| 11 | * |
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| 12 | * FFmpeg is distributed in the hope that it will be useful, |
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| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
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| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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| 15 | * Lesser General Public License for more details. |
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| 16 | * |
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| 17 | * You should have received a copy of the GNU Lesser General Public |
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| 18 | * License along with FFmpeg; if not, write to the Free Software |
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| 19 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
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| 20 | */ |
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| 21 | |||
| 22 | #include "libavcodec/get_bits.h" |
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| 23 | #include "avformat.h" |
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| 24 | #include "rawdec.h" |
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| 25 | |||
| 26 | static int h261_probe(AVProbeData *p) |
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| 27 | { |
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| 28 | uint32_t code= -1; |
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| 29 | int i; |
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| 30 | int valid_psc=0; |
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| 31 | int invalid_psc=0; |
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| 32 | int next_gn=0; |
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| 33 | int src_fmt=0; |
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| 34 | GetBitContext gb; |
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| 35 | |||
| 36 | init_get_bits8(&gb, p->buf, p->buf_size); |
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| 37 | |||
| 38 | for(i=0; i |
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| 39 | if ((code & 0x01ff0000) || !(code & 0xff00)) { |
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| 40 | code = (code<<8) + get_bits(&gb, 8); |
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| 41 | i += 7; |
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| 42 | } else |
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| 43 | code = (code<<1) + get_bits1(&gb); |
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| 44 | if ((code & 0xffff0000) == 0x10000) { |
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| 45 | int gn= (code>>12)&0xf; |
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| 46 | if(!gn) |
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| 47 | src_fmt= code&8; |
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| 48 | if(gn != next_gn) invalid_psc++; |
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| 49 | else valid_psc++; |
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| 50 | |||
| 51 | if(src_fmt){ // CIF |
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| 52 | next_gn= (gn+1 )%13; |
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| 53 | }else{ //QCIF |
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| 54 | next_gn= (gn+1+!!gn)% 7; |
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| 55 | } |
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| 56 | } |
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| 57 | } |
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| 58 | if(valid_psc > 2*invalid_psc + 6){ |
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| 59 | return AVPROBE_SCORE_EXTENSION; |
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| 60 | }else if(valid_psc > 2*invalid_psc + 2) |
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| 61 | return AVPROBE_SCORE_EXTENSION / 2; |
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| 62 | return 0; |
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| 63 | } |
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| 64 | |||
| 65 | FF_DEF_RAWVIDEO_DEMUXER(h261, "raw H.261", h261_probe, "h261", AV_CODEC_ID_H261) |