AVR demuxer

Signed-off-by: Paul B Mahol <onemda@gmail.com>

1 files changed, 95 insertions, 0 deletions

diff --git a/libavformat/avr.c b/libavformat/avr.c
new file mode 100644
index 0000000000..1e212fc828
--- /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",
+};