Commit ad8159e0 authored by Nicolas George's avatar Nicolas George Committed by Anton Khirnov

libavfilter: Add asettb filter for setting timebase for audio

Ported asettb (including the sr option for audio sample rate) from FFmpeg,
and copied/modified the existing settb documentation for asettb.
Signed-off-by: default avatarKaterina Barone-Adesi <katerinab+libav@gmail.com>
Signed-off-by: default avatarAnton Khirnov <anton@khirnov.net>
parent f6774f90
......@@ -18,6 +18,7 @@ version <next>:
- LucasArts SMUSH VIMA audio decoder (ADPCM)
- LucasArts SMUSH demuxer
- MP2 encoding via TwoLAME
- asettb filter
version 10:
......
......@@ -260,6 +260,47 @@ asetpts=expr=N/SR/TB
asetpts='(RTCTIME - RTCSTART) / (TB * 1000000)"
@end example
@section asettb
Set the timebase to use for the output frames timestamps.
It is mainly useful for testing timebase configuration.
This filter accepts the following parameters:
@table @option
@item expr
The expression which is evaluated into the output timebase.
@end table
The expression can contain the constants @var{PI}, @var{E}, @var{PHI}, @var{AVTB} (the
default timebase), @var{intb} (the input timebase), and @var{sr} (the sample rate,
audio only).
The default value for the input is @var{intb}.
Some examples:
@example
# Set the timebase to 1/25:
settb=1/25
# Set the timebase to 1/10:
settb=0.1
# Set the timebase to 1001/1000:
settb=1+0.001
# Set the timebase to 2*intb:
settb=2*intb
# Set the default timebase value:
settb=AVTB
# Set the timebase to twice the sample rate:
asettb=sr*2
@end example
@section ashowinfo
......
......@@ -28,6 +28,7 @@ OBJS-$(CONFIG_AFORMAT_FILTER) += af_aformat.o
OBJS-$(CONFIG_AMIX_FILTER) += af_amix.o
OBJS-$(CONFIG_ANULL_FILTER) += af_anull.o
OBJS-$(CONFIG_ASETPTS_FILTER) += setpts.o
OBJS-$(CONFIG_ASETTB_FILTER) += settb.o
OBJS-$(CONFIG_ASHOWINFO_FILTER) += af_ashowinfo.o
OBJS-$(CONFIG_ASPLIT_FILTER) += split.o
OBJS-$(CONFIG_ASYNCTS_FILTER) += af_asyncts.o
......
......@@ -48,6 +48,7 @@ void avfilter_register_all(void)
REGISTER_FILTER(AMIX, amix, af);
REGISTER_FILTER(ANULL, anull, af);
REGISTER_FILTER(ASETPTS, asetpts, af);
REGISTER_FILTER(ASETTB, asettb, af);
REGISTER_FILTER(ASHOWINFO, ashowinfo, af);
REGISTER_FILTER(ASPLIT, asplit, af);
REGISTER_FILTER(ASYNCTS, asyncts, af);
......
......@@ -32,6 +32,7 @@
#include "libavutil/mathematics.h"
#include "libavutil/opt.h"
#include "libavutil/rational.h"
#include "audio.h"
#include "avfilter.h"
#include "internal.h"
#include "video.h"
......@@ -42,6 +43,7 @@ static const char *const var_names[] = {
"PI",
"AVTB", /* default timebase 1/AV_TIME_BASE */
"intb", /* input timebase */
"sr", /* sample rate */
NULL
};
......@@ -51,6 +53,7 @@ enum var_name {
VAR_PI,
VAR_AVTB,
VAR_INTB,
VAR_SR,
VAR_VARS_NB
};
......@@ -74,6 +77,7 @@ static int config_output_props(AVFilterLink *outlink)
settb->var_values[VAR_PI] = M_PI;
settb->var_values[VAR_AVTB] = av_q2d(AV_TIME_BASE_Q);
settb->var_values[VAR_INTB] = av_q2d(inlink->time_base);
settb->var_values[VAR_SR] = inlink->sample_rate;
outlink->w = inlink->w;
outlink->h = inlink->h;
......@@ -116,12 +120,13 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
}
#define OFFSET(x) offsetof(SetTBContext, x)
#define FLAGS AV_OPT_FLAG_VIDEO_PARAM
#define FLAGS AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_AUDIO_PARAM
static const AVOption options[] = {
{ "expr", "Expression determining the output timebase", OFFSET(tb_expr), AV_OPT_TYPE_STRING, { .str = "intb" }, .flags = FLAGS },
{ NULL },
};
#if CONFIG_SETTB_FILTER
static const AVClass settb_class = {
.class_name = "settb",
.item_name = av_default_item_name,
......@@ -150,7 +155,7 @@ static const AVFilterPad avfilter_vf_settb_outputs[] = {
AVFilter ff_vf_settb = {
.name = "settb",
.description = NULL_IF_CONFIG_SMALL("Set timebase for the output link."),
.description = NULL_IF_CONFIG_SMALL("Set timebase for the video output link."),
.priv_size = sizeof(SetTBContext),
.priv_class = &settb_class,
......@@ -159,3 +164,41 @@ AVFilter ff_vf_settb = {
.outputs = avfilter_vf_settb_outputs,
};
#endif /* CONFIG_SETTB_FILTER */
#if CONFIG_ASETTB_FILTER
static const AVClass asettb_class = {
.class_name = "asettb",
.item_name = av_default_item_name,
.option = options,
.version = LIBAVUTIL_VERSION_INT,
};
static const AVFilterPad avfilter_af_asettb_inputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_AUDIO,
.get_audio_buffer = ff_null_get_audio_buffer,
.filter_frame = filter_frame,
},
{ NULL }
};
static const AVFilterPad avfilter_af_asettb_outputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_AUDIO,
.config_props = config_output_props,
},
{ NULL }
};
AVFilter ff_af_asettb = {
.name = "asettb",
.description = NULL_IF_CONFIG_SMALL("Set timebase for the audio output link."),
.priv_size = sizeof(SetTBContext),
.inputs = avfilter_af_asettb_inputs,
.outputs = avfilter_af_asettb_outputs,
.priv_class = &asettb_class,
};
#endif /* CONFIG_ASETTB_FILTER */
......@@ -30,7 +30,7 @@
#include "libavutil/version.h"
#define LIBAVFILTER_VERSION_MAJOR 4
#define LIBAVFILTER_VERSION_MINOR 3
#define LIBAVFILTER_VERSION_MINOR 4
#define LIBAVFILTER_VERSION_MICRO 0
#define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \
......
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