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mirror of https://git.videolan.org/git/ffmpeg.git synced 2024-09-12 02:14:56 +02:00
ffmpeg/libavfilter/asrc_anullsrc.c
Reinhard Tartler 737eb5976f Merge libavcore into libavutil
It is pretty hopeless that other considerable projects will adopt
libavutil alone in other projects. Projects that need small footprint
are better off with more specialized libraries such as gnulib or rather
just copy the necessary parts that they need. With this in mind, nobody
is helped by having libavutil and libavcore split. In order to ease
maintenance inside and around FFmpeg and to reduce confusion where to
put common code, avcore's functionality is merged (back) to avutil.

Signed-off-by: Reinhard Tartler <siretart@tauware.de>
2011-02-15 16:18:21 +01:00

97 lines
3.0 KiB
C

/*
* 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
*/
/**
* @file
* null audio source
*/
#include "avfilter.h"
#include "libavutil/audioconvert.h"
typedef struct {
int64_t channel_layout;
int64_t sample_rate;
} ANullContext;
static int init(AVFilterContext *ctx, const char *args, void *opaque)
{
ANullContext *priv = ctx->priv;
char channel_layout_str[128] = "";
priv->sample_rate = 44100;
priv->channel_layout = AV_CH_LAYOUT_STEREO;
if (args)
sscanf(args, "%"PRId64":%s", &priv->sample_rate, channel_layout_str);
if (priv->sample_rate < 0) {
av_log(ctx, AV_LOG_ERROR, "Invalid negative sample rate: %"PRId64"\n", priv->sample_rate);
return AVERROR(EINVAL);
}
if (*channel_layout_str)
if (!(priv->channel_layout = av_get_channel_layout(channel_layout_str))
&& sscanf(channel_layout_str, "%"PRId64, &priv->channel_layout) != 1) {
av_log(ctx, AV_LOG_ERROR, "Invalid value '%s' for channel layout\n",
channel_layout_str);
return AVERROR(EINVAL);
}
return 0;
}
static int config_props(AVFilterLink *outlink)
{
ANullContext *priv = outlink->src->priv;
char buf[128];
int chans_nb;
outlink->sample_rate = priv->sample_rate;
outlink->channel_layout = priv->channel_layout;
chans_nb = av_get_channel_layout_nb_channels(priv->channel_layout);
av_get_channel_layout_string(buf, sizeof(buf), chans_nb, priv->channel_layout);
av_log(outlink->src, AV_LOG_INFO,
"sample_rate:%"PRId64 " channel_layout:%"PRId64 " channel_layout_description:'%s'\n",
priv->sample_rate, priv->channel_layout, buf);
return 0;
}
static int request_frame(AVFilterLink *link)
{
return -1;
}
AVFilter avfilter_asrc_anullsrc = {
.name = "anullsrc",
.description = NULL_IF_CONFIG_SMALL("Null audio source, never return audio frames."),
.init = init,
.priv_size = sizeof(ANullContext),
.inputs = (AVFilterPad[]) {{ .name = NULL}},
.outputs = (AVFilterPad[]) {{ .name = "default",
.type = AVMEDIA_TYPE_AUDIO,
.config_props = config_props,
.request_frame = request_frame, },
{ .name = NULL}},
};