1/*
2 * On2 VP8 parser for Ogg
3 * Copyright (C) 2013 James Almer
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22#include "libavutil/intreadwrite.h"
23#include "avformat.h"
24#include "internal.h"
25#include "oggdec.h"
26
27#define VP8_HEADER_SIZE 26
28
29static int vp8_header(AVFormatContext *s, int idx)
30{
31    struct ogg *ogg = s->priv_data;
32    struct ogg_stream *os = ogg->streams + idx;
33    uint8_t *p = os->buf + os->pstart;
34    AVStream *st = s->streams[idx];
35    AVRational framerate;
36
37    if (os->psize < 7 || p[0] != 0x4f)
38        return 0;
39
40    switch (p[5]){
41    case 0x01:
42        if (os->psize < VP8_HEADER_SIZE) {
43            av_log(s, AV_LOG_ERROR, "Invalid OggVP8 header packet");
44            return AVERROR_INVALIDDATA;
45        }
46
47        if (p[6] != 1) {
48            av_log(s, AV_LOG_WARNING, "Unknown OggVP8 version %d.%d\n", p[6], p[7]);
49            return AVERROR_INVALIDDATA;
50        }
51
52        st->codec->width            = AV_RB16(p +  8);
53        st->codec->height           = AV_RB16(p + 10);
54        st->sample_aspect_ratio.num = AV_RB24(p + 12);
55        st->sample_aspect_ratio.den = AV_RB24(p + 15);
56        framerate.den               = AV_RB32(p + 18);
57        framerate.num               = AV_RB32(p + 22);
58
59        avpriv_set_pts_info(st, 64, framerate.num, framerate.den);
60        st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
61        st->codec->codec_id   = AV_CODEC_ID_VP8;
62        st->need_parsing      = AVSTREAM_PARSE_HEADERS;
63        break;
64    case 0x02:
65        if (p[6] != 0x20)
66            return AVERROR_INVALIDDATA;
67        ff_vorbis_comment(s, &st->metadata, p + 7, os->psize - 7, 1);
68        break;
69    default:
70        av_log(s, AV_LOG_ERROR, "Unknown VP8 header type 0x%02X\n", p[5]);
71        return AVERROR_INVALIDDATA;
72    }
73
74    return 1;
75}
76
77static uint64_t vp8_gptopts(AVFormatContext *s, int idx, uint64_t granule, int64_t *dts)
78{
79    struct ogg *ogg = s->priv_data;
80    struct ogg_stream *os = ogg->streams + idx;
81
82    uint64_t pts  = (granule >> 32);
83    uint32_t dist = (granule >>  3) & 0x07ffffff;
84
85    if (!dist)
86        os->pflags |= AV_PKT_FLAG_KEY;
87
88    if (dts)
89        *dts = pts;
90
91    return pts;
92}
93
94static int vp8_packet(AVFormatContext *s, int idx)
95{
96    struct ogg *ogg = s->priv_data;
97    struct ogg_stream *os = ogg->streams + idx;
98    uint8_t *p = os->buf + os->pstart;
99
100    if ((!os->lastpts || os->lastpts == AV_NOPTS_VALUE) && !(os->flags & OGG_FLAG_EOS)) {
101        int seg;
102        int duration;
103        uint8_t *last_pkt = p;
104        uint8_t *next_pkt;
105
106        seg = os->segp;
107        duration = (last_pkt[0] >> 4) & 1;
108        next_pkt = last_pkt += os->psize;
109        for (; seg < os->nsegs; seg++) {
110            if (os->segments[seg] < 255) {
111                duration += (last_pkt[0] >> 4) & 1;
112                last_pkt  = next_pkt + os->segments[seg];
113            }
114            next_pkt += os->segments[seg];
115        }
116        os->lastpts = os->lastdts = vp8_gptopts(s, idx, os->granule, NULL) - duration;
117        if(s->streams[idx]->start_time == AV_NOPTS_VALUE) {
118            s->streams[idx]->start_time = os->lastpts;
119            if (s->streams[idx]->duration)
120                s->streams[idx]->duration -= s->streams[idx]->start_time;
121        }
122    }
123
124    if (os->psize > 0)
125        os->pduration = (p[0] >> 4) & 1;
126
127    return 0;
128}
129
130const struct ogg_codec ff_vp8_codec = {
131    .magic     = "OVP80",
132    .magicsize = 5,
133    .header    = vp8_header,
134    .packet    = vp8_packet,
135    .gptopts   = vp8_gptopts,
136    .nb_header = 1,
137};
138