oggdec: add support for VP8 demuxing

Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>

1 files changed, 142 insertions, 0 deletions

diff --git a/libavformat/oggparsevp8.c b/libavformat/oggparsevp8.c
new file mode 100644
index 0000000000..b4f71de017
--- /dev/null
+++ b/libavformat/oggparsevp8.c
@@ -0,0 +1,142 @@
+/*
+ * On2 VP8 parser for Ogg
+ * Copyright (C) 2013 James Almer
+ *
+ * This file is part of Libav.
+ *
+ * Libav is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * Libav is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "libavutil/intreadwrite.h"
+
+#include "avformat.h"
+#include "internal.h"
+#include "oggdec.h"
+
+#define VP8_HEADER_SIZE 26
+
+static int vp8_header(AVFormatContext *s, int idx)
+{
+    struct ogg *ogg = s->priv_data;
+    struct ogg_stream *os = ogg->streams + idx;
+    uint8_t *p = os->buf + os->pstart;
+    AVStream *st = s->streams[idx];
+    AVRational framerate;
+
+    if (os->psize < 7 || p[0] != 0x4f)
+        return 0;
+
+    switch (p[5]){
+    case 0x01:
+        if (os->psize < VP8_HEADER_SIZE) {
+            av_log(s, AV_LOG_ERROR, "Invalid OggVP8 header packet");
+            return AVERROR_INVALIDDATA;
+        }
+
+        if (p[6] != 1) {
+            av_log(s, AV_LOG_WARNING,
+                   "Unknown OggVP8 version %d.%d\n", p[6], p[7]);
+            return AVERROR_INVALIDDATA;
+        }
+
+        st->codec->width            = AV_RB16(p +  8);
+        st->codec->height           = AV_RB16(p + 10);
+        st->sample_aspect_ratio.num = AV_RB24(p + 12);
+        st->sample_aspect_ratio.den = AV_RB24(p + 15);
+        framerate.num               = AV_RB32(p + 18);
+        framerate.den               = AV_RB32(p + 22);
+
+        avpriv_set_pts_info(st, 64, framerate.den, framerate.num);
+        st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
+        st->codec->codec_id   = AV_CODEC_ID_VP8;
+        st->need_parsing      = AVSTREAM_PARSE_HEADERS;
+        break;
+    case 0x02:
+        if (p[6] != 0x20)
+            return AVERROR_INVALIDDATA;
+        ff_vorbis_stream_comment(s, st, p + 7, os->psize - 7);
+        break;
+    default:
+        av_log(s, AV_LOG_ERROR, "Unknown VP8 header type 0x%02X\n", p[5]);
+        return AVERROR_INVALIDDATA;
+    }
+
+    return 1;
+}
+
+static uint64_t vp8_gptopts(AVFormatContext *s, int idx,
+                            uint64_t granule, int64_t *dts)
+{
+    struct ogg *ogg = s->priv_data;
+    struct ogg_stream *os = ogg->streams + idx;
+
+    uint64_t pts  = (granule >> 32);
+    uint32_t dist = (granule >>  3) & 0x07ffffff;
+
+    if (!dist)
+        os->pflags |= AV_PKT_FLAG_KEY;
+
+    if (dts)
+        *dts = pts;
+
+    return pts;
+}
+
+static int vp8_packet(AVFormatContext *s, int idx)
+{
+    struct ogg *ogg = s->priv_data;
+    struct ogg_stream *os = ogg->streams + idx;
+    uint8_t *p = os->buf + os->pstart;
+
+    if ((!os->lastpts || os->lastpts == AV_NOPTS_VALUE) &&
+        !(os->flags & OGG_FLAG_EOS)) {
+        int seg;
+        int duration;
+        uint8_t *last_pkt = p;
+        uint8_t *next_pkt;
+
+        seg = os->segp;
+        duration = (last_pkt[0] >> 4) & 1;
+        next_pkt = last_pkt += os->psize;
+        for (; seg < os->nsegs; seg++) {
+            if (os->segments[seg] < 255) {
+                duration += (last_pkt[0] >> 4) & 1;
+                last_pkt  = next_pkt + os->segments[seg];
+            }
+            next_pkt += os->segments[seg];
+        }
+        os->lastpts =
+        os->lastdts = vp8_gptopts(s, idx, os->granule, NULL) - duration;
+        if(s->streams[idx]->start_time == AV_NOPTS_VALUE) {
+            s->streams[idx]->start_time = os->lastpts;
+            if (s->streams[idx]->duration)
+                s->streams[idx]->duration -= s->streams[idx]->start_time;
+        }
+    }
+
+    if (os->psize > 0)
+        os->pduration = (p[0] >> 4) & 1;
+
+    return 0;
+}
+
+const struct ogg_codec ff_vp8_codec = {
+    .magic     = "OVP80",
+    .magicsize = 5,
+    .header    = vp8_header,
+    .packet    = vp8_packet,
+    .gptopts   = vp8_gptopts,
+    .nb_header = 1,
+};