[FFmpeg-devel] [PATCH] avformat: add Sample Dump eXchange demuxer

Paul B Mahol onemda at gmail.com
Sat Jan 21 20:30:34 EET 2017


Signed-off-by: Paul B Mahol <onemda at gmail.com>
---
 libavformat/Makefile     |  1 +
 libavformat/allformats.c |  1 +
 libavformat/sdxdec.c     | 90 ++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 92 insertions(+)
 create mode 100644 libavformat/sdxdec.c

diff --git a/libavformat/Makefile b/libavformat/Makefile
index f30bc94..036e7a9 100644
--- a/libavformat/Makefile
+++ b/libavformat/Makefile
@@ -437,6 +437,7 @@ OBJS-$(CONFIG_SBG_DEMUXER)               += sbgdec.o
 OBJS-$(CONFIG_SDP_DEMUXER)               += rtsp.o
 OBJS-$(CONFIG_SDR2_DEMUXER)              += sdr2.o
 OBJS-$(CONFIG_SDS_DEMUXER)               += sdsdec.o
+OBJS-$(CONFIG_SDX_DEMUXER)               += sdxdec.o
 OBJS-$(CONFIG_SEGAFILM_DEMUXER)          += segafilm.o
 OBJS-$(CONFIG_SEGMENT_MUXER)             += segment.o
 OBJS-$(CONFIG_SHORTEN_DEMUXER)           += shortendec.o rawdec.o
diff --git a/libavformat/allformats.c b/libavformat/allformats.c
index e30305b..b8590ce 100644
--- a/libavformat/allformats.c
+++ b/libavformat/allformats.c
@@ -276,6 +276,7 @@ void av_register_all(void)
     REGISTER_DEMUXER (SDP,              sdp);
     REGISTER_DEMUXER (SDR2,             sdr2);
     REGISTER_DEMUXER (SDS,              sds);
+    REGISTER_DEMUXER (SDX,              sdx);
 #if CONFIG_RTPDEC
     ff_register_rtp_dynamic_payload_handlers();
     ff_register_rdt_dynamic_payload_handlers();
diff --git a/libavformat/sdxdec.c b/libavformat/sdxdec.c
new file mode 100644
index 0000000..e8e7a4f
--- /dev/null
+++ b/libavformat/sdxdec.c
@@ -0,0 +1,90 @@
+/*
+ * SDX demuxer
+ * Copyright (c) 2017 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/avstring.h"
+#include "libavutil/intreadwrite.h"
+#include "avformat.h"
+#include "internal.h"
+#include "pcm.h"
+
+static int sdx_probe(AVProbeData *p)
+{
+    if (AV_RB32(p->buf) == AV_RB32("SDX:"))
+        return AVPROBE_SCORE_EXTENSION;
+    return 0;
+}
+
+static int sdx_read_header(AVFormatContext *s)
+{
+    AVStream *st;
+    int depth, length;
+
+    avio_skip(s->pb, 4);
+    while (!avio_feof(s->pb)) {
+        if (avio_r8(s->pb) == 0x1a)
+            break;
+    }
+    if (avio_r8(s->pb) != 1)
+        return AVERROR_INVALIDDATA;
+    length = avio_r8(s->pb);
+    avio_skip(s->pb, length);
+    avio_skip(s->pb, 4);
+    depth = avio_r8(s->pb);
+
+    st = avformat_new_stream(s, NULL);
+    if (!st)
+        return AVERROR(ENOMEM);
+
+    st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
+    st->codecpar->channels = 1;
+    st->codecpar->sample_rate = avio_rl32(s->pb);
+    switch (depth) {
+    case 8:
+        st->codecpar->codec_id = AV_CODEC_ID_PCM_U8;
+        break;
+    case 16:
+        st->codecpar->codec_id = AV_CODEC_ID_PCM_U16LE;
+        break;
+    case 24:
+        st->codecpar->codec_id = AV_CODEC_ID_PCM_U24LE;
+        break;
+    case 32:
+        st->codecpar->codec_id = AV_CODEC_ID_PCM_U32LE;
+        break;
+    default:
+        return AVERROR_INVALIDDATA;
+    }
+    avio_skip(s->pb, 16);
+    st->codecpar->block_align = depth / 8;
+
+    return 0;
+}
+
+AVInputFormat ff_sdx_demuxer = {
+    .name           = "sdx",
+    .long_name      = NULL_IF_CONFIG_SMALL("Sample Dump eXchange"),
+    .read_probe     = sdx_probe,
+    .read_header    = sdx_read_header,
+    .read_packet    = ff_pcm_read_packet,
+    .read_seek      = ff_pcm_read_seek,
+    .extensions     = "sdx",
+    .flags          = AVFMT_GENERIC_INDEX,
+};
-- 
2.9.3



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