Statistics
| Branch: | Revision:

ffmpeg / libavformat / oggparsedirac.c @ 72415b2a

History | View | Annotate | Download (3.33 KB)

1
/*
2
 * Copyright (C) 2008  David Conrad
3
 *
4
 * This file is part of FFmpeg.
5
 *
6
 * FFmpeg is free software; you can redistribute it and/or
7
 * modify it under the terms of the GNU Lesser General Public
8
 * License as published by the Free Software Foundation; either
9
 * version 2.1 of the License, or (at your option) any later version.
10
 *
11
 * FFmpeg is distributed in the hope that it will be useful,
12
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14
 * Lesser General Public License for more details.
15
 *
16
 * You should have received a copy of the GNU Lesser General Public
17
 * License along with FFmpeg; if not, write to the Free Software
18
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19
 */
20

    
21
#include "libavcodec/get_bits.h"
22
#include "libavcodec/dirac.h"
23
#include "avformat.h"
24
#include "oggdec.h"
25

    
26
static int dirac_header(AVFormatContext *s, int idx)
27
{
28
    struct ogg *ogg = s->priv_data;
29
    struct ogg_stream *os = ogg->streams + idx;
30
    AVStream *st = s->streams[idx];
31
    dirac_source_params source;
32
    GetBitContext gb;
33

    
34
    // already parsed the header
35
    if (st->codec->codec_id == CODEC_ID_DIRAC)
36
        return 0;
37

    
38
    init_get_bits(&gb, os->buf + os->pstart + 13, (os->psize - 13) * 8);
39
    if (ff_dirac_parse_sequence_header(st->codec, &gb, &source) < 0)
40
        return -1;
41

    
42
    st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
43
    st->codec->codec_id = CODEC_ID_DIRAC;
44
    // dirac in ogg always stores timestamps as though the video were interlaced
45
    st->time_base = (AVRational){st->codec->time_base.num, 2*st->codec->time_base.den};
46
    return 1;
47
}
48

    
49
// various undocument things: granule is signed (only for dirac!)
50
static uint64_t dirac_gptopts(AVFormatContext *s, int idx, uint64_t granule,
51
                              int64_t *dts_out)
52
{
53
    int64_t gp = granule;
54
    struct ogg *ogg = s->priv_data;
55
    struct ogg_stream *os = ogg->streams + idx;
56

    
57
    unsigned dist  = ((gp >> 14) & 0xff00) | (gp & 0xff);
58
    int64_t  dts   = (gp >> 31);
59
    int64_t  pts   = dts + ((gp >> 9) & 0x1fff);
60

    
61
    if (!dist)
62
        os->pflags |= PKT_FLAG_KEY;
63

    
64
    if (dts_out)
65
        *dts_out = dts;
66

    
67
    return pts;
68
}
69

    
70
static int old_dirac_header(AVFormatContext *s, int idx)
71
{
72
    struct ogg *ogg = s->priv_data;
73
    struct ogg_stream *os = ogg->streams + idx;
74
    AVStream *st = s->streams[idx];
75
    uint8_t *buf = os->buf + os->pstart;
76

    
77
    if (buf[0] != 'K')
78
        return 0;
79

    
80
    st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
81
    st->codec->codec_id = CODEC_ID_DIRAC;
82
    st->time_base.den = AV_RB32(buf+8);
83
    st->time_base.num = AV_RB32(buf+12);
84
    return 1;
85
}
86

    
87
static uint64_t old_dirac_gptopts(AVFormatContext *s, int idx, uint64_t gp,
88
                                  int64_t *dts)
89
{
90
    struct ogg *ogg = s->priv_data;
91
    struct ogg_stream *os = ogg->streams + idx;
92
    uint64_t iframe = gp >> 30;
93
    uint64_t pframe = gp & 0x3fffffff;
94

    
95
    if (!pframe)
96
        os->pflags |= PKT_FLAG_KEY;
97

    
98
    return iframe + pframe;
99
}
100

    
101
const struct ogg_codec ff_dirac_codec = {
102
    .magic = "BBCD\0",
103
    .magicsize = 5,
104
    .header = dirac_header,
105
    .gptopts = dirac_gptopts,
106
    .granule_is_start = 1,
107
};
108

    
109
const struct ogg_codec ff_old_dirac_codec = {
110
    .magic = "KW-DIRAC",
111
    .magicsize = 8,
112
    .header = old_dirac_header,
113
    .gptopts = old_dirac_gptopts,
114
    .granule_is_start = 1,
115
};