[FFmpeg-devel] [PATCH] AVR demuxer

[Paul B Mahol]

Signed-off-by: Paul B Mahol <onemda at gmail.com>
---
 doc/general.texi         |  2 +
 libavformat/Makefile     |  1 +
 libavformat/allformats.c |  1 +
 libavformat/avr.c        | 95 ++++++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 99 insertions(+)
 create mode 100644 libavformat/avr.c

diff --git a/doc/general.texi b/doc/general.texi
index 8ec1d28..9768339 100644
--- a/doc/general.texi
+++ b/doc/general.texi
@@ -150,6 +150,8 @@ library:
 @item ASF                       @tab X @tab X
 @item AVI                       @tab X @tab X
 @item AVISynth                  @tab   @tab X
+ at item AVR                       @tab   @tab X
+    @tab Audio format used on Mac.
 @item AVS                       @tab   @tab X
     @tab Multimedia format used by the Creature Shock game.
 @item Beam Software SIFF        @tab   @tab X
diff --git a/libavformat/Makefile b/libavformat/Makefile
index ff16b3b..5176c4f 100644
--- a/libavformat/Makefile
+++ b/libavformat/Makefile
@@ -56,6 +56,7 @@ OBJS-$(CONFIG_AVI_DEMUXER)               += avidec.o
 OBJS-$(CONFIG_AVI_MUXER)                 += avienc.o
 OBJS-$(CONFIG_AVISYNTH)                  += avisynth.o
 OBJS-$(CONFIG_AVM2_MUXER)                += swfenc.o swf.o
+OBJS-$(CONFIG_AVR_DEMUXER)               += avr.o
 OBJS-$(CONFIG_AVS_DEMUXER)               += avs.o vocdec.o voc.o
 OBJS-$(CONFIG_BETHSOFTVID_DEMUXER)       += bethsoftvid.o
 OBJS-$(CONFIG_BFI_DEMUXER)               += bfi.o
diff --git a/libavformat/allformats.c b/libavformat/allformats.c
index 3551394..ea345e5 100644
--- a/libavformat/allformats.c
+++ b/libavformat/allformats.c
@@ -69,6 +69,7 @@ void av_register_all(void)
     REGISTER_MUXDEMUX (AVI, avi);
     REGISTER_DEMUXER  (AVISYNTH, avisynth);
     REGISTER_MUXER    (AVM2, avm2);
+    REGISTER_DEMUXER  (AVR, avr);
     REGISTER_DEMUXER  (AVS, avs);
     REGISTER_DEMUXER  (BETHSOFTVID, bethsoftvid);
     REGISTER_DEMUXER  (BFI, bfi);
diff --git a/libavformat/avr.c b/libavformat/avr.c
new file mode 100644
index 0000000..1e212fc
--- /dev/null
+++ b/libavformat/avr.c
@@ -0,0 +1,95 @@
+/*
+ * AVR demuxer
+ * Copyright (c) 2012 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"
+#include "rawdec.h"
+
+static int avr_probe(AVProbeData *p)
+{
+    if (AV_RL32(p->buf) == MKTAG('2', 'B', 'I', 'T'))
+        return AVPROBE_SCORE_MAX / 2;
+    return 0;
+}
+
+static int avr_read_header(AVFormatContext *s)
+{
+    uint16_t chan, sign, bps;
+    AVStream *st;
+
+    st = avformat_new_stream(s, NULL);
+    if (!st)
+        return AVERROR(ENOMEM);
+
+    st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
+
+    avio_skip(s->pb, 4); // magic
+    avio_skip(s->pb, 8); // sample_name
+
+    chan = avio_rb16(s->pb);
+    if (!chan) {
+        st->codec->channels = 1;
+    } else if (chan == 0xFFFFu) {
+        st->codec->channels = 2;
+    } else {
+        av_log_ask_for_sample(s, "unknown number of channels\n");
+        return AVERROR_PATCHWELCOME;
+    }
+
+    st->codec->bits_per_coded_sample = bps = avio_rb16(s->pb);
+
+    sign = avio_rb16(s->pb);
+
+    avio_skip(s->pb, 2); // loop
+    avio_skip(s->pb, 2); // midi
+
+    st->codec->sample_rate = avio_rb32(s->pb);
+    avio_skip(s->pb, 4 * 3);
+    avio_skip(s->pb, 2 * 3);
+    avio_skip(s->pb, 20);
+    avio_skip(s->pb, 64);
+
+    if (!sign && bps == 8) {
+        st->codec->codec_id = AV_CODEC_ID_PCM_U8;
+    } else if (!sign && bps == 16) {
+        st->codec->codec_id = AV_CODEC_ID_PCM_U16BE;
+    } else if (sign == 0xFFFFu && bps == 8) {
+        st->codec->codec_id = AV_CODEC_ID_PCM_S8;
+    } else if (sign == 0xFFFFu && bps == 16) {
+        st->codec->codec_id = AV_CODEC_ID_PCM_S16BE;
+    } else {
+        av_log_ask_for_sample(s, "unknown bits per sample\n");
+        return AVERROR_PATCHWELCOME;
+    }
+
+    avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
+    return 0;
+}
+
+AVInputFormat ff_avr_demuxer = {
+    .name           = "avr",
+    .long_name      = NULL_IF_CONFIG_SMALL("Audio Visual Resarch (AVR)"),
+    .read_probe     = avr_probe,
+    .read_header    = avr_read_header,
+    .read_packet    = ff_raw_read_partial_packet,
+    .extensions     = "avr",
+};
-- 
1.7.11.2