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authorAurelien Jacobs <aurel@gnuage.org>2010-08-30 21:17:34 +0000
committerAurelien Jacobs <aurel@gnuage.org>2010-08-30 21:17:34 +0000
commite94204dfd88b80c21f8756ea354dc12e1c4b206e (patch)
tree65a2d898465227b31bb1ebc700312783e9564720 /libavformat/pcm.c
parent79ce0f002e3078ceb68375dd80805cafbd2fcf9e (diff)
downloadffmpeg-e94204dfd88b80c21f8756ea354dc12e1c4b206e.tar.gz
move pcm demuxers to their own file
Originally committed as revision 24993 to svn://svn.ffmpeg.org/ffmpeg/trunk
Diffstat (limited to 'libavformat/pcm.c')
-rw-r--r--libavformat/pcm.c55
1 files changed, 55 insertions, 0 deletions
diff --git a/libavformat/pcm.c b/libavformat/pcm.c
new file mode 100644
index 0000000000..5de23af1cb
--- /dev/null
+++ b/libavformat/pcm.c
@@ -0,0 +1,55 @@
+/*
+ * PCM common functions
+ * Copyright (c) 2003 Fabrice Bellard
+ *
+ * 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 "avformat.h"
+#include "pcm.h"
+
+int pcm_read_seek(AVFormatContext *s,
+ int stream_index, int64_t timestamp, int flags)
+{
+ AVStream *st;
+ int block_align, byte_rate;
+ int64_t pos, ret;
+
+ st = s->streams[0];
+
+ block_align = st->codec->block_align ? st->codec->block_align :
+ (av_get_bits_per_sample(st->codec->codec_id) * st->codec->channels) >> 3;
+ byte_rate = st->codec->bit_rate ? st->codec->bit_rate >> 3 :
+ block_align * st->codec->sample_rate;
+
+ if (block_align <= 0 || byte_rate <= 0)
+ return -1;
+ if (timestamp < 0) timestamp = 0;
+
+ /* compute the position by aligning it to block_align */
+ pos = av_rescale_rnd(timestamp * byte_rate,
+ st->time_base.num,
+ st->time_base.den * (int64_t)block_align,
+ (flags & AVSEEK_FLAG_BACKWARD) ? AV_ROUND_DOWN : AV_ROUND_UP);
+ pos *= block_align;
+
+ /* recompute exact position */
+ st->cur_dts = av_rescale(pos, st->time_base.den, byte_rate * (int64_t)st->time_base.num);
+ if ((ret = url_fseek(s->pb, pos + s->data_offset, SEEK_SET)) < 0)
+ return ret;
+ return 0;
+}