af_sidechaincompress.c File Reference

Sidechain compressor filter. More...

#include "libavutil/avassert.h"
#include "libavutil/channel_layout.h"
#include "libavutil/common.h"
#include "libavutil/opt.h"
#include "audio.h"
#include "avfilter.h"
#include "formats.h"
#include "internal.h"

Go to the source code of this file.

Data Structures
struct	SidechainCompressContext

Macros
#define	OFFSET(x)   offsetof(SidechainCompressContext, x)
#define	A   AV_OPT_FLAG_AUDIO_PARAM
#define	F   AV_OPT_FLAG_FILTERING_PARAM
#define	FAKE_INFINITY   (65536.0 * 65536.0)
#define	IS_FAKE_INFINITY(value)   (fabs(value-FAKE_INFINITY) < 1.0)

Functions
	AVFILTER_DEFINE_CLASS (sidechaincompress)
static av_cold int	init (AVFilterContext *ctx)
static float	hermite_interpolation (float x, float x0, float x1, float p0, float p1, float m0, float m1)
static double	output_gain (double lin_slope, double ratio, double thres, double knee, double knee_start, double knee_stop, double compressed_knee_stop, int detection)
static int	filter_frame (AVFilterLink *link, AVFrame *frame)
static int	request_frame (AVFilterLink *outlink)
static int	query_formats (AVFilterContext *ctx)
static int	config_output (AVFilterLink *outlink)

Variables
static const AVOption	sidechaincompress_options []
static const AVFilterPad	sidechaincompress_inputs []
static const AVFilterPad	sidechaincompress_outputs []
AVFilter	ff_af_sidechaincompress

Detailed Description

Sidechain compressor filter.

Definition in file af_sidechaincompress.c.

Macro Definition Documentation

#define OFFSET

(

x

)

offsetof(SidechainCompressContext, x)

Definition at line 58 of file af_sidechaincompress.c.

#define A   AV_OPT_FLAG_AUDIO_PARAM

Definition at line 59 of file af_sidechaincompress.c.

#define F   AV_OPT_FLAG_FILTERING_PARAM

Definition at line 60 of file af_sidechaincompress.c.

#define FAKE_INFINITY   (65536.0 * 65536.0)

Definition at line 117 of file af_sidechaincompress.c.

#define IS_FAKE_INFINITY

(

value

)

(fabs(value-FAKE_INFINITY) < 1.0)

Definition at line 120 of file af_sidechaincompress.c.

Referenced by output_gain().

Function Documentation

AVFILTER_DEFINE_CLASS

(

sidechaincompress

)

static av_cold int init ( AVFilterContext *  ctx )

static

Definition at line 80 of file af_sidechaincompress.c.

static float hermite_interpolation ( float  x, float  x0, float  x1, float  p0, float  p1, float  m0, float  m1  )

inlinestatic

Definition at line 93 of file af_sidechaincompress.c.

Referenced by output_gain().

static double output_gain ( double  lin_slope, double  ratio, double  thres, double  knee, double  knee_start, double  knee_stop, double  compressed_knee_stop, int  detection  )

static

Definition at line 122 of file af_sidechaincompress.c.

Referenced by filter_frame().

static int filter_frame ( AVFilterLink *  link, AVFrame *  frame  )

static

Definition at line 149 of file af_sidechaincompress.c.

static int request_frame ( AVFilterLink *  outlink )

static

Definition at line 216 of file af_sidechaincompress.c.

static int query_formats ( AVFilterContext *  ctx )

static

Definition at line 237 of file af_sidechaincompress.c.

static int config_output ( AVFilterLink *  outlink )

static

Definition at line 279 of file af_sidechaincompress.c.

Variable Documentation

const AVOption sidechaincompress_options[]

static

Initial value:

= {
    { "threshold", "set threshold",    OFFSET(threshold), AV_OPT_TYPE_DOUBLE, {.dbl=0.125}, 0.000976563,    1, A|F },
    { "ratio",     "set ratio",        OFFSET(ratio),     AV_OPT_TYPE_DOUBLE, {.dbl=2},               1,   20, A|F },
    { "attack",    "set attack",       OFFSET(attack),    AV_OPT_TYPE_DOUBLE, {.dbl=20},           0.01, 2000, A|F },
    { "release",   "set release",      OFFSET(release),   AV_OPT_TYPE_DOUBLE, {.dbl=250},          0.01, 9000, A|F },
    { "makeup",    "set make up gain", OFFSET(makeup),    AV_OPT_TYPE_DOUBLE, {.dbl=2},               1,   64, A|F },
    { "knee",      "set knee",         OFFSET(knee),      AV_OPT_TYPE_DOUBLE, {.dbl=2.82843},         1,    8, A|F },
    { "link",      "set link type",    OFFSET(link),      AV_OPT_TYPE_INT,    {.i64=0},               0,    1, A|F, "link" },
    {   "average", 0,                  0,                 AV_OPT_TYPE_CONST,  {.i64=0},               0,    0, A|F, "link" },
    {   "maximum", 0,                  0,                 AV_OPT_TYPE_CONST,  {.i64=1},               0,    0, A|F, "link" },
    { "detection", "set detection",    OFFSET(detection), AV_OPT_TYPE_INT,    {.i64=1},               0,    1, A|F, "detection" },
    {   "peak",    0,                  0,                 AV_OPT_TYPE_CONST,  {.i64=0},               0,    0, A|F, "detection" },
    {   "rms",     0,                  0,                 AV_OPT_TYPE_CONST,  {.i64=1},               0,    0, A|F, "detection" },
    { NULL }
}

Definition at line 62 of file af_sidechaincompress.c.

const AVFilterPad sidechaincompress_inputs[]

static

Initial value:

= {
    {
        .name           = "main",
        .type           = AVMEDIA_TYPE_AUDIO,
        .filter_frame   = filter_frame,
        .needs_writable = 1,
        .needs_fifo     = 1,
    },{
        .name           = "sidechain",
        .type           = AVMEDIA_TYPE_AUDIO,
        .filter_frame   = filter_frame,
        .needs_fifo     = 1,
    },
    { NULL }
}

Definition at line 303 of file af_sidechaincompress.c.

const AVFilterPad sidechaincompress_outputs[]

static

Initial value:

= {
    {
        .name          = "default",
        .type          = AVMEDIA_TYPE_AUDIO,
        .config_props  = config_output,
        .request_frame = request_frame,
    },
    { NULL }
}

Definition at line 319 of file af_sidechaincompress.c.

AVFilter ff_af_sidechaincompress

Initial value:

= {
    .name           = "sidechaincompress",
    .description    = NULL_IF_CONFIG_SMALL("Sidechain compressor."),
    .priv_size      = sizeof(SidechainCompressContext),
    .priv_class     = &sidechaincompress_class,
    .init           = init,
    .query_formats  = query_formats,
    .inputs         = sidechaincompress_inputs,
    .outputs        = sidechaincompress_outputs,
}

Definition at line 329 of file af_sidechaincompress.c.