oggdec: add support for Opus codec.

This patch also introduces CODEC_ID_OPUS.

libavcodec/avcodec.h

@@ -420,6 +420,7 @@ enum CodecID {
     CODEC_ID_SONIC       = MKBETAG('S','O','N','C'),
     CODEC_ID_SONIC_LS    = MKBETAG('S','O','N','L'),
     CODEC_ID_PAF_AUDIO   = MKBETAG('P','A','F','A'),
+    CODEC_ID_OPUS        = MKBETAG('O','P','U','S'),
 
     /* subtitle codecs */
     CODEC_ID_FIRST_SUBTITLE = 0x17000,          ///< A dummy ID pointing at the start of subtitle codecs.

libavformat/Makefile

@@ -203,6 +203,7 @@ OBJS-$(CONFIG_OGG_DEMUXER)               += oggdec.o         \
                                             oggparsedirac.o  \
                                             oggparseflac.o   \
                                             oggparseogm.o    \
+                                            oggparseopus.o   \
                                             oggparseskeleton.o \
                                             oggparsespeex.o  \
                                             oggparsetheora.o \

libavformat/oggdec.c

@@ -46,6 +46,7 @@ static const struct ogg_codec * const ogg_codecs[] = {
     &ff_theora_codec,
     &ff_flac_codec,
     &ff_celt_codec,
+    &ff_opus_codec,
     &ff_old_dirac_codec,
     &ff_old_flac_codec,
     &ff_ogm_video_codec,

libavformat/oggdec.h

@@ -108,6 +108,7 @@ extern const struct ogg_codec ff_ogm_text_codec;
 extern const struct ogg_codec ff_ogm_video_codec;
 extern const struct ogg_codec ff_old_dirac_codec;
 extern const struct ogg_codec ff_old_flac_codec;
+extern const struct ogg_codec ff_opus_codec;
 extern const struct ogg_codec ff_skeleton_codec;
 extern const struct ogg_codec ff_speex_codec;
 extern const struct ogg_codec ff_theora_codec;

libavformat/oggparseopus.c

@@ -0,0 +1,135 @@
+/*
+ * Opus parser for Ogg
+ * Copyright (c) 2012 Nicolas George
+ *
+ * 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 <string.h>
+
+#include "libavutil/intreadwrite.h"
+#include "avformat.h"
+#include "internal.h"
+#include "oggdec.h"
+
+struct oggopus_private {
+    int need_comments;
+    unsigned pre_skip;
+    int64_t cur_dts;
+};
+
+#define OPUS_HEAD_SIZE 19
+
+static int opus_header(AVFormatContext *avf, int idx)
+{
+    struct ogg *ogg = avf->priv_data;
+    struct ogg_stream *os = &ogg->streams[idx];
+    AVStream *st = avf->streams[idx];
+    struct oggopus_private *priv = os->private;
+    uint8_t *packet = os->buf + os->pstart;
+    uint8_t *extradata;
+
+    if (!priv) {
+        priv = os->private = av_mallocz(sizeof(*priv));
+        if (!priv)
+            return AVERROR(ENOMEM);
+    }
+    if (os->flags & OGG_FLAG_BOS) {
+        if (os->psize < OPUS_HEAD_SIZE || (AV_RL8(packet + 8) & 0xF0) != 0)
+            return AVERROR_INVALIDDATA;
+        st->codec->codec_type  = AVMEDIA_TYPE_AUDIO;
+        st->codec->codec_id    = CODEC_ID_OPUS;
+        st->codec->channels    = AV_RL8 (packet + 9);
+        priv->pre_skip         = AV_RL16(packet + 10);
+        /*orig_sample_rate     = AV_RL32(packet + 12);*/
+        /*gain                 = AV_RL16(packet + 16);*/
+        /*channel_map          = AV_RL8 (packet + 18);*/
+
+        extradata = av_malloc(os->psize + FF_INPUT_BUFFER_PADDING_SIZE);
+        if (!extradata)
+            return AVERROR(ENOMEM);
+        memcpy(extradata, packet, os->psize);
+        st->codec->extradata = extradata;
+        st->codec->extradata_size = os->psize;
+
+        st->codec->sample_rate = 48000;
+        avpriv_set_pts_info(st, 64, 1, 48000);
+        priv->need_comments = 1;
+        return 1;
+    }
+
+    if (priv->need_comments) {
+        if (os->psize < 8 || memcmp(packet, "OpusTags", 8))
+            return AVERROR_INVALIDDATA;
+        ff_vorbis_comment(avf, &st->metadata, packet + 8, os->psize - 8);
+        priv->need_comments--;
+        return 1;
+    }
+    return 0;
+}
+
+static int opus_packet(AVFormatContext *avf, int idx)
+{
+    struct ogg *ogg = avf->priv_data;
+    struct ogg_stream *os = &ogg->streams[idx];
+    AVStream *st = avf->streams[idx];
+    struct oggopus_private *priv = os->private;
+    uint8_t *packet = os->buf + os->pstart;
+    unsigned toc, toc_config, toc_count, frame_size, nb_frames = 1;
+
+    if (!os->psize)
+        return AVERROR_INVALIDDATA;
+    toc = *packet;
+    toc_config = toc >> 3;
+    toc_count  = toc & 3;
+    frame_size = toc_config < 12 ? FFMAX(480, 960 * (toc_config & 3)) :
+                 toc_config < 16 ? 480 << (toc_config & 1) :
+                                   120 << (toc_config & 3);
+    if (toc_count == 3) {
+        if (os->psize < 2)
+            return AVERROR_INVALIDDATA;
+        nb_frames = packet[1] & 0x3F;
+    } else if (toc_count) {
+        nb_frames = 2;
+    }
+    os->pduration = frame_size * nb_frames;
+    if (os->lastpts != AV_NOPTS_VALUE) {
+        if (st->start_time == AV_NOPTS_VALUE)
+            st->start_time = os->lastpts;
+        priv->cur_dts = os->lastdts = os->lastpts -= priv->pre_skip;
+    }
+    priv->cur_dts += os->pduration;
+    if ((os->flags & OGG_FLAG_EOS)) {
+        int64_t skip = priv->cur_dts - os->granule + priv->pre_skip;
+        skip = FFMIN(skip, os->pduration);
+        if (skip > 0) {
+            os->pduration = skip < os->pduration ? os->pduration - skip : 1;
+            av_log(avf, AV_LOG_WARNING,
+                   "Last packet must be truncated to %d (unimplemented).\n",
+                   os->pduration);
+        }
+    }
+    return 0;
+}
+
+const struct ogg_codec ff_opus_codec = {
+    .name      = "Opus",
+    .magic     = "OpusHead",
+    .magicsize = 8,
+    .header    = opus_header,
+    .packet    = opus_packet,
+};

libavformat/version.h

@@ -31,7 +31,7 @@
 
 #define LIBAVFORMAT_VERSION_MAJOR 54
 #define LIBAVFORMAT_VERSION_MINOR 17
-#define LIBAVFORMAT_VERSION_MICRO 100
+#define LIBAVFORMAT_VERSION_MICRO 101
 
 #define LIBAVFORMAT_VERSION_INT AV_VERSION_INT(LIBAVFORMAT_VERSION_MAJOR, \
                                                LIBAVFORMAT_VERSION_MINOR, \