[FFmpeg-devel] [PATCH] avformat: add genh demuxer

[Paul B Mahol]

Signed-off-by: Paul B Mahol <onemda at gmail.com>
---
 libavformat/Makefile     |   1 +
 libavformat/allformats.c |   1 +
 libavformat/genh.c       | 113 +++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 115 insertions(+)
 create mode 100644 libavformat/genh.c

diff --git a/libavformat/Makefile b/libavformat/Makefile
index 2971912..a66bd17 100644
--- a/libavformat/Makefile
+++ b/libavformat/Makefile
@@ -177,6 +177,7 @@ OBJS-$(CONFIG_G722_MUXER)                += rawenc.o
 OBJS-$(CONFIG_G723_1_DEMUXER)            += g723_1.o
 OBJS-$(CONFIG_G723_1_MUXER)              += rawenc.o
 OBJS-$(CONFIG_G729_DEMUXER)              += g729dec.o
+OBJS-$(CONFIG_GENH_DEMUXER)              += genh.o
 OBJS-$(CONFIG_H261_DEMUXER)              += h261dec.o rawdec.o
 OBJS-$(CONFIG_H261_MUXER)                += rawenc.o
 OBJS-$(CONFIG_H263_DEMUXER)              += h263dec.o rawdec.o
diff --git a/libavformat/allformats.c b/libavformat/allformats.c
index 0ccde9d..dbd7719 100644
--- a/libavformat/allformats.c
+++ b/libavformat/allformats.c
@@ -138,6 +138,7 @@ void av_register_all(void)
     REGISTER_MUXDEMUX(G722,             g722);
     REGISTER_MUXDEMUX(G723_1,           g723_1);
     REGISTER_DEMUXER (G729,             g729);
+    REGISTER_DEMUXER (GENH,             genh);
     REGISTER_MUXDEMUX(GIF,              gif);
     REGISTER_DEMUXER (GSM,              gsm);
     REGISTER_MUXDEMUX(GXF,              gxf);
diff --git a/libavformat/genh.c b/libavformat/genh.c
new file mode 100644
index 0000000..b9b9c46
--- /dev/null
+++ b/libavformat/genh.c
@@ -0,0 +1,113 @@
+/*
+ * GENH demuxer
+ * Copyright (c) 2015 Paul B Mahol
+ *
+ * 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"
+
+static int genh_probe(AVProbeData *p)
+{
+    if (AV_RL32(p->buf) != MKTAG('G','E','N','H'))
+        return 0;
+
+    return AVPROBE_SCORE_MAX / 3 * 2;
+}
+
+static int genh_read_header(AVFormatContext *s)
+{
+    unsigned start_offset, header_size, codec;
+    int align;
+    AVStream *st;
+
+    avio_skip(s->pb, 4);
+
+    st = avformat_new_stream(s, NULL);
+    if (!st)
+        return AVERROR(ENOMEM);
+
+    st->codec->codec_type  = AVMEDIA_TYPE_AUDIO;
+    st->codec->channels    = avio_rl32(s->pb);
+    if (st->codec->channels <= 0)
+        return AVERROR_INVALIDDATA;
+    if (st->codec->channels == 2)
+        st->codec->channel_layout = AV_CH_LAYOUT_STEREO;
+    align                  = avio_rl32(s->pb);
+    if (align < 0 || align > INT_MAX / st->codec->channels)
+        return AVERROR_INVALIDDATA;
+    st->codec->block_align = align * st->codec->channels;
+    st->codec->sample_rate = avio_rl32(s->pb);
+    avio_skip(s->pb, 4);
+    st->duration = avio_rl32(s->pb);
+
+    codec = avio_rl32(s->pb);
+    switch (codec) {
+    case  1:
+    case 11: st->codec->bits_per_coded_sample = 4;
+             st->codec->codec_id = AV_CODEC_ID_ADPCM_IMA_WAV;    break;
+    case  3: st->codec->codec_id = st->codec->block_align > 0 ?
+                                   AV_CODEC_ID_PCM_S16BE_PLANAR :
+                                   AV_CODEC_ID_PCM_S16BE;        break;
+    case  4: st->codec->codec_id = st->codec->block_align > 0 ?
+                                   AV_CODEC_ID_PCM_S16LE_PLANAR :
+                                   AV_CODEC_ID_PCM_S16LE;        break;
+    case  5: st->codec->codec_id = st->codec->block_align > 0 ?
+                                   AV_CODEC_ID_PCM_S8_PLANAR :
+                                   AV_CODEC_ID_PCM_S8;           break;
+    case 13: st->codec->codec_id = AV_CODEC_ID_PCM_U8;           break;
+    default:
+             avpriv_request_sample(s, "codec %d", codec);
+             return AVERROR_PATCHWELCOME;
+    }
+
+    start_offset = avio_rl32(s->pb);
+    header_size  = avio_rl32(s->pb);
+
+    if (header_size > start_offset)
+        return AVERROR_INVALIDDATA;
+
+    if (header_size == 0)
+        start_offset = 0x800;
+
+    avio_skip(s->pb, start_offset - avio_tell(s->pb));
+
+    avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
+
+    return 0;
+}
+
+static int genh_read_packet(AVFormatContext *s, AVPacket *pkt)
+{
+    AVCodecContext *codec = s->streams[0]->codec;
+    int ret;
+
+    ret = av_get_packet(s->pb, pkt, codec->block_align ? codec->block_align : 1024 * codec->channels);
+    pkt->stream_index = 0;
+    return ret;
+}
+
+AVInputFormat ff_genh_demuxer = {
+    .name           = "genh",
+    .long_name      = NULL_IF_CONFIG_SMALL("GENeric Header"),
+    .read_probe     = genh_probe,
+    .read_header    = genh_read_header,
+    .read_packet    = genh_read_packet,
+    .extensions     = "genh",
+};
-- 
1.9.1