Add muxer for IVF format.

libavformat/ivfenc.c

+/*
+ * Copyright (c) 2010 Reimar Döffinger
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg 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.
+ *
+ * FFmpeg 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 FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+#include "avformat.h"
+#include "libavutil/intreadwrite.h"
+
+static int ivf_write_header(AVFormatContext *s)
+{
+    AVCodecContext *ctx;
+    ByteIOContext *pb = s->pb;
+
+    if (s->nb_streams != 1) {
+        av_log(s, AV_LOG_ERROR, "Format supports only exactly one video stream\n");
+        return AVERROR(EINVAL);
+    }
+    ctx = s->streams[0]->codec;
+    if (ctx->codec_type != CODEC_TYPE_VIDEO || ctx->codec_id != CODEC_ID_VP8) {
+        av_log(s, AV_LOG_ERROR, "Currently only VP8 is supported!\n");
+        return AVERROR(EINVAL);
+    }
+    put_buffer(pb, "DKIF", 4);
+    put_le16(pb, 0); // version
+    put_le16(pb, 32); // header length
+    put_le32(pb, ctx->codec_tag ? ctx->codec_tag : AV_RL32("VP80"));
+    put_le16(pb, ctx->width);
+    put_le16(pb, ctx->height);
+    put_le32(pb, s->streams[0]->time_base.den);
+    put_le32(pb, s->streams[0]->time_base.num);
+    put_le64(pb, s->streams[0]->duration); // TODO: duration or number of frames?!?
+
+    return 0;
+}
+
+static int ivf_write_packet(AVFormatContext *s, AVPacket *pkt)
+{
+    ByteIOContext *pb = s->pb;
+    put_le32(pb, pkt->size);
+    put_le64(pb, pkt->pts);
+    put_buffer(pb, pkt->data, pkt->size);
+    put_flush_packet(pb);
+
+    return 0;
+}
+
+AVOutputFormat ivf_muxer = {
+    .name = "ivf",
+    .long_name = NULL_IF_CONFIG_SMALL("On2 IVF"),
+    .extensions = "ivf",
+    .audio_codec = CODEC_ID_NONE,
+    .video_codec = CODEC_ID_VP8,
+    .write_header = ivf_write_header,
+    .write_packet = ivf_write_packet,
+};