ast: Rename ast.c -> astdec.c

Signed-off-by: James Almer <jamrial@gmail.com>

1 files changed, 127 insertions, 0 deletions

diff --git a/libavformat/astdec.c b/libavformat/astdec.c
new file mode 100644
index 0000000000..5f69f47d44
--- /dev/null
+++ b/libavformat/astdec.c
@@ -0,0 +1,127 @@
+/*
+ * AST 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/channel_layout.h"
+#include "libavutil/intreadwrite.h"
+#include "avformat.h"
+#include "internal.h"
+
+static int ast_probe(AVProbeData *p)
+{
+    if (AV_RL32(p->buf) == MKTAG('S','T','R','M') &&
+        AV_RB16(p->buf + 10) &&
+        AV_RB16(p->buf + 12) &&
+        AV_RB32(p->buf + 16))
+        return AVPROBE_SCORE_MAX / 3 * 2;
+    return 0;
+}
+
+static int ast_read_header(AVFormatContext *s)
+{
+    int codec, depth;
+    AVStream *st;
+
+    st = avformat_new_stream(s, NULL);
+    if (!st)
+        return AVERROR(ENOMEM);
+
+    avio_skip(s->pb, 8);
+    codec = avio_rb16(s->pb);
+    switch (codec) {
+    case 0:
+        st->codec->codec_id = AV_CODEC_ID_ADPCM_AFC;
+        break;
+    case 1:
+        st->codec->codec_id = AV_CODEC_ID_PCM_S16BE_PLANAR;
+        break;
+    default:
+        av_log(s, AV_LOG_ERROR, "unsupported codec %d\n", codec);
+    }
+
+    depth = avio_rb16(s->pb);
+    if (depth != 16) {
+        av_log_ask_for_sample(s, "unsupported depth %d\n", depth);
+        return AVERROR_INVALIDDATA;
+    }
+
+    st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
+    st->codec->channels = avio_rb16(s->pb);
+    if (!st->codec->channels)
+        return AVERROR_INVALIDDATA;
+
+    if (st->codec->channels == 2)
+        st->codec->channel_layout = AV_CH_LAYOUT_STEREO;
+    else if (st->codec->channels == 4)
+        st->codec->channel_layout = AV_CH_LAYOUT_4POINT0;
+
+    avio_skip(s->pb, 2);
+    st->codec->sample_rate = avio_rb32(s->pb);
+    if (st->codec->sample_rate <= 0)
+        return AVERROR_INVALIDDATA;
+    st->start_time         = 0;
+    st->duration           = avio_rb32(s->pb);
+    avio_skip(s->pb, 40);
+    avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
+
+    return 0;
+}
+
+static int ast_read_packet(AVFormatContext *s, AVPacket *pkt)
+{
+    uint32_t type, size;
+    int64_t pos;
+    int ret;
+
+    if (url_feof(s->pb))
+        return AVERROR_EOF;
+
+    pos  = avio_tell(s->pb);
+    type = avio_rl32(s->pb);
+    size = avio_rb32(s->pb);
+    if (size > INT_MAX / s->streams[0]->codec->channels)
+        return AVERROR_INVALIDDATA;
+
+    size *= s->streams[0]->codec->channels;
+    if ((ret = avio_skip(s->pb, 24)) < 0) // padding
+        return ret;
+
+    if (type == MKTAG('B','L','C','K')) {
+        ret = av_get_packet(s->pb, pkt, size);
+        pkt->stream_index = 0;
+        pkt->pos = pos;
+    } else {
+        av_log(s, AV_LOG_ERROR, "unknown chunk %x\n", type);
+        avio_skip(s->pb, size);
+        ret = AVERROR_INVALIDDATA;
+    }
+
+    return ret;
+}
+
+AVInputFormat ff_ast_demuxer = {
+    .name           = "ast",
+    .long_name      = NULL_IF_CONFIG_SMALL("AST (Audio Stream)"),
+    .read_probe     = ast_probe,
+    .read_header    = ast_read_header,
+    .read_packet    = ast_read_packet,
+    .extensions     = "ast",
+    .flags          = AVFMT_GENERIC_INDEX,
+};