1/**
2      Copyright (C) 2005  Matthieu CASTET, Alex Beregszaszi
3
4      Permission is hereby granted, free of charge, to any person
5      obtaining a copy of this software and associated documentation
6      files (the "Software"), to deal in the Software without
7      restriction, including without limitation the rights to use, copy,
8      modify, merge, publish, distribute, sublicense, and/or sell copies
9      of the Software, and to permit persons to whom the Software is
10      furnished to do so, subject to the following conditions:
11
12      The above copyright notice and this permission notice shall be
13      included in all copies or substantial portions of the Software.
14
15      THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
16      EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17      MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
18      NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
19      HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
20      WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21      OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
22      DEALINGS IN THE SOFTWARE.
23**/
24
25#include <stdlib.h>
26#include "libavutil/bswap.h"
27#include "libavcodec/get_bits.h"
28#include "avformat.h"
29#include "internal.h"
30#include "oggdec.h"
31
32struct theora_params {
33    int gpshift;
34    int gpmask;
35    unsigned version;
36};
37
38static int
39theora_header (AVFormatContext * s, int idx)
40{
41    struct ogg *ogg = s->priv_data;
42    struct ogg_stream *os = ogg->streams + idx;
43    AVStream *st = s->streams[idx];
44    struct theora_params *thp = os->private;
45    int cds = st->codec->extradata_size + os->psize + 2;
46    uint8_t *cdp;
47
48    if(!(os->buf[os->pstart] & 0x80))
49        return 0;
50
51    if(!thp){
52        thp = av_mallocz(sizeof(*thp));
53        os->private = thp;
54    }
55
56    if (os->buf[os->pstart] == 0x80) {
57        GetBitContext gb;
58        int width, height;
59
60        init_get_bits(&gb, os->buf + os->pstart, os->psize*8);
61
62        skip_bits_long(&gb, 7*8); /* 0x80"theora" */
63
64        thp->version = get_bits_long(&gb, 24);
65        if (thp->version < 0x030100)
66        {
67            av_log(s, AV_LOG_ERROR,
68                "Too old or unsupported Theora (%x)\n", thp->version);
69            return -1;
70        }
71
72        width  = get_bits(&gb, 16) << 4;
73        height = get_bits(&gb, 16) << 4;
74        avcodec_set_dimensions(st->codec, width, height);
75
76        if (thp->version >= 0x030400)
77            skip_bits(&gb, 100);
78
79        if (thp->version >= 0x030200) {
80            width  = get_bits_long(&gb, 24);
81            height = get_bits_long(&gb, 24);
82            if (   width  <= st->codec->width  && width  > st->codec->width-16
83                && height <= st->codec->height && height > st->codec->height-16)
84                avcodec_set_dimensions(st->codec, width, height);
85
86            skip_bits(&gb, 16);
87        }
88        st->codec->time_base.den = get_bits_long(&gb, 32);
89        st->codec->time_base.num = get_bits_long(&gb, 32);
90        if (!(st->codec->time_base.num > 0 && st->codec->time_base.den > 0)) {
91            av_log(s, AV_LOG_WARNING, "Invalid time base in theora stream, assuming 25 FPS\n");
92            st->codec->time_base.num = 1;
93            st->codec->time_base.den = 25;
94        }
95        avpriv_set_pts_info(st, 64, st->codec->time_base.num, st->codec->time_base.den);
96
97        st->sample_aspect_ratio.num = get_bits_long(&gb, 24);
98        st->sample_aspect_ratio.den = get_bits_long(&gb, 24);
99
100        if (thp->version >= 0x030200)
101            skip_bits_long(&gb, 38);
102        if (thp->version >= 0x304000)
103            skip_bits(&gb, 2);
104
105        thp->gpshift = get_bits(&gb, 5);
106        thp->gpmask = (1 << thp->gpshift) - 1;
107
108        st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
109        st->codec->codec_id = CODEC_ID_THEORA;
110        st->need_parsing = AVSTREAM_PARSE_HEADERS;
111
112    } else if (os->buf[os->pstart] == 0x83) {
113        ff_vorbis_comment (s, &st->metadata, os->buf + os->pstart + 7, os->psize - 8);
114    }
115
116    st->codec->extradata = av_realloc (st->codec->extradata,
117                                       cds + FF_INPUT_BUFFER_PADDING_SIZE);
118    cdp = st->codec->extradata + st->codec->extradata_size;
119    *cdp++ = os->psize >> 8;
120    *cdp++ = os->psize & 0xff;
121    memcpy (cdp, os->buf + os->pstart, os->psize);
122    st->codec->extradata_size = cds;
123
124    return 1;
125}
126
127static uint64_t
128theora_gptopts(AVFormatContext *ctx, int idx, uint64_t gp, int64_t *dts)
129{
130    struct ogg *ogg = ctx->priv_data;
131    struct ogg_stream *os = ogg->streams + idx;
132    struct theora_params *thp = os->private;
133    uint64_t iframe = gp >> thp->gpshift;
134    uint64_t pframe = gp & thp->gpmask;
135
136    if (thp->version < 0x030201)
137        iframe++;
138
139    if(!pframe)
140        os->pflags |= AV_PKT_FLAG_KEY;
141
142    if (dts)
143        *dts = iframe + pframe;
144
145    return iframe + pframe;
146}
147
148const struct ogg_codec ff_theora_codec = {
149    .magic = "\200theora",
150    .magicsize = 7,
151    .header = theora_header,
152    .gptopts = theora_gptopts
153};
154