avformat: add APAC demuxer

1 files changed, 86 insertions, 0 deletions

diff --git a/libavformat/apac.c b/libavformat/apac.c
new file mode 100644
index 0000000000..18970e19dd
--- /dev/null
+++ b/libavformat/apac.c
@@ -0,0 +1,86 @@
+/*
+ * APAC demuxer
+ * Copyright (c) 2022 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 "demux.h"
+#include "internal.h"
+#include "rawdec.h"
+
+static int apac_probe(const AVProbeData *p)
+{
+    if (AV_RB32(p->buf) == MKBETAG('A','P','A','C') &&
+        AV_RB32(p->buf + 8) == MKBETAG('P','R','O','F') &&
+        AV_RB32(p->buf + 12) == MKBETAG('N','A','D',' '))
+        return AVPROBE_SCORE_MAX;
+
+    return 0;
+}
+
+static int apac_read_header(AVFormatContext *s)
+{
+    AVIOContext *pb = s->pb;
+    uint32_t chunk_size;
+    AVStream *st;
+    int64_t pos;
+
+    avio_skip(pb, 16);
+    chunk_size = avio_rl32(pb);
+    avio_skip(pb, chunk_size);
+    if (avio_rb32(pb) != MKBETAG('P','F','M','T'))
+        return AVERROR_INVALIDDATA;
+    chunk_size = avio_rl32(pb);
+    pos = avio_tell(pb);
+    avio_skip(pb, 2);
+    st = avformat_new_stream(s, NULL);
+    if (!st)
+        return AVERROR(ENOMEM);
+    st->codecpar->codec_type  = AVMEDIA_TYPE_AUDIO;
+    st->codecpar->codec_id    = AV_CODEC_ID_APAC;
+    st->codecpar->ch_layout.nb_channels = avio_rl16(pb);
+    st->codecpar->sample_rate = avio_rl32(pb);
+    if (st->codecpar->ch_layout.nb_channels <= 0 ||
+        st->codecpar->ch_layout.nb_channels >  2 ||
+        st->codecpar->sample_rate <= 0)
+        return AVERROR_INVALIDDATA;
+    avio_skip(pb, 2);
+    st->codecpar->bits_per_coded_sample = avio_rl16(pb);
+    avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
+    avio_skip(pb, (chunk_size + pos) - avio_tell(pb) + (chunk_size & 1));
+    if (avio_rb32(pb) != MKBETAG('P','A','D',' '))
+        return AVERROR_INVALIDDATA;
+    avio_skip(pb, 4);
+
+    return 0;
+}
+
+const AVInputFormat ff_apac_demuxer = {
+    .name           = "apac",
+    .long_name      = NULL_IF_CONFIG_SMALL("raw APAC"),
+    .read_probe     = apac_probe,
+    .read_header    = apac_read_header,
+    .read_packet    = ff_raw_read_partial_packet,
+    .extensions     = "apc",
+    .flags          = AVFMT_NOBINSEARCH | AVFMT_NOGENSEARCH | AVFMT_NO_BYTE_SEEK | AVFMT_NOTIMESTAMPS,
+    .raw_codec_id   = AV_CODEC_ID_APAC,
+    .priv_data_size = sizeof(FFRawDemuxerContext),
+    .priv_class     = &ff_raw_demuxer_class,
+};