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
26static 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!)
50static 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 |= AV_PKT_FLAG_KEY;
63
64    if (dts_out)
65        *dts_out = dts;
66
67    return pts;
68}
69
70static 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
87static 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 |= AV_PKT_FLAG_KEY;
97
98    return iframe + pframe;
99}
100
101const 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
109const 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};
116