[FFmpeg-devel] [PATCH v2] avformat/ogg: Add partial support for OggPCM demuxing

A G oreo639 at outlook.com
Thu May 28 03:34:08 EEST 2020


This adds partial support for OggPCM muxing.

It is effectively just an updated version of this:
https://ffmpeg.org/pipermail/ffmpeg-devel/2013-July/145556.html
---
 libavformat/Makefile      |   1 +
 libavformat/oggdec.c      |   1 +
 libavformat/oggdec.h      |   1 +
 libavformat/oggparsepcm.c | 123 ++++++++++++++++++++++++++++++++++++++
 4 files changed, 126 insertions(+)
 create mode 100644 libavformat/oggparsepcm.c

diff --git a/libavformat/Makefile b/libavformat/Makefile
index efe82f9f08..145407bb40 100644
--- a/libavformat/Makefile
+++ b/libavformat/Makefile
@@ -364,6 +364,7 @@ OBJS-$(CONFIG_OGG_DEMUXER)               += oggdec.o         \
                                             oggparseflac.o   \
                                             oggparseogm.o    \
                                             oggparseopus.o   \
+                                            oggparsepcm.o    \
                                             oggparseskeleton.o \
                                             oggparsespeex.o  \
                                             oggparsetheora.o \
diff --git a/libavformat/oggdec.c b/libavformat/oggdec.c
index 1a3acbb55e..6a95485680 100644
--- a/libavformat/oggdec.c
+++ b/libavformat/oggdec.c
@@ -49,6 +49,7 @@ static const struct ogg_codec * const ogg_codecs[] = {
     &ff_flac_codec,
     &ff_celt_codec,
     &ff_opus_codec,
+    &ff_pcm_codec,
     &ff_vp8_codec,
     &ff_old_dirac_codec,
     &ff_old_flac_codec,
diff --git a/libavformat/oggdec.h b/libavformat/oggdec.h
index 629a1d6262..ae001b4ded 100644
--- a/libavformat/oggdec.h
+++ b/libavformat/oggdec.h
@@ -124,6 +124,7 @@ 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_pcm_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;
diff --git a/libavformat/oggparsepcm.c b/libavformat/oggparsepcm.c
new file mode 100644
index 0000000000..3a1470ac99
--- /dev/null
+++ b/libavformat/oggparsepcm.c
@@ -0,0 +1,123 @@
+/*
+ * PCM parser for Ogg
+ * Copyright (c) 2013 James Almer
+ *
+ * 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 "libavutil/intreadwrite.h"
+#include "avformat.h"
+#include "internal.h"
+#include "oggdec.h"
+
+struct oggpcm_private {
+    int vorbis_comment;
+    uint32_t extra_headers;
+};
+
+static const struct ogg_pcm_codec {
+    uint32_t codec_id;
+    uint32_t format_id;
+} ogg_pcm_codecs[] = {
+    { AV_CODEC_ID_PCM_S8,    0x00 },
+    { AV_CODEC_ID_PCM_U8,    0x01 },
+    { AV_CODEC_ID_PCM_S16LE, 0x02 },
+    { AV_CODEC_ID_PCM_S16BE, 0x03 },
+    { AV_CODEC_ID_PCM_S24LE, 0x04 },
+    { AV_CODEC_ID_PCM_S24BE, 0x05 },
+    { AV_CODEC_ID_PCM_S32LE, 0x06 },
+    { AV_CODEC_ID_PCM_S32BE, 0x07 },
+    { AV_CODEC_ID_PCM_F32LE, 0x20 },
+    { AV_CODEC_ID_PCM_F32BE, 0x21 },
+    { AV_CODEC_ID_PCM_F64LE, 0x22 },
+    { AV_CODEC_ID_PCM_F64BE, 0x23 },
+};
+
+static const struct ogg_pcm_codec *ogg_get_pcm_codec_id(uint32_t format_id)
+{
+    int i;
+
+    for (i = 0; i < FF_ARRAY_ELEMS(ogg_pcm_codecs); i++)
+        if (ogg_pcm_codecs[i].format_id == format_id)
+            return &ogg_pcm_codecs[i];
+
+    return NULL;
+}
+
+static int pcm_header(AVFormatContext *as, int idx)
+{
+    struct ogg *ogg = as->priv_data;
+    struct ogg_stream *os = ogg->streams + idx;
+    struct oggpcm_private *priv = os->private;
+    const struct ogg_pcm_codec *pcm;
+    AVStream *st = as->streams[idx];
+    uint8_t *p = os->buf + os->pstart;
+    uint16_t major, minor;
+    uint32_t format_id;
+
+    if (!priv) {
+        priv = os->private = av_mallocz(sizeof(*priv));
+        if (!priv)
+            return AVERROR(ENOMEM);
+    }
+
+    if (os->flags & OGG_FLAG_BOS) {
+        if (os->psize < 28) {
+            av_log(as, AV_LOG_ERROR, "Invalid OggPCM header packet");
+            return AVERROR_INVALIDDATA;
+        }
+
+        major = AV_RB16(p + 8);
+        minor = AV_RB16(p + 10);
+        if (major) {
+            av_log(as, AV_LOG_ERROR, "Unsupported OggPCM version %u.%u\n", major, minor);
+            return AVERROR_INVALIDDATA;
+        }
+
+        format_id = AV_RB32(p + 12);
+        pcm = ogg_get_pcm_codec_id(format_id);
+        if (!pcm) {
+            av_log(as, AV_LOG_ERROR, "Unsupported PCM format ID 0x%X\n", format_id);
+            return AVERROR_INVALIDDATA;
+        }
+
+        st->codecpar->codec_type  = AVMEDIA_TYPE_AUDIO;
+        st->codecpar->codec_id    = pcm->codec_id;
+        st->codecpar->sample_rate = AV_RB32(p + 16);
+        st->codecpar->channels    = AV_RB8 (p + 21);
+        priv->extra_headers    = AV_RB32(p + 24);
+        priv->vorbis_comment   = 1;
+        avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
+    } else if (priv->vorbis_comment) {
+        ff_vorbis_stream_comment(as, st, p, os->psize);
+        priv->vorbis_comment   = 0;
+    } else if (priv->extra_headers) {
+        // TODO: Support for channel mapping and conversion headers.
+        priv->extra_headers--;
+    } else
+        return 0;
+
+    return 1;
+}
+
+const struct ogg_codec ff_pcm_codec = {
+    .name      = "OggPCM",
+    .magic     = "PCM     ",
+    .magicsize = 8,
+    .header    = pcm_header,
+    .nb_header = 2,
+};
--
2.26.2



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