af_compand.c File Reference

audio compand filter More...

#include "libavutil/avassert.h"
#include "libavutil/avstring.h"
#include "libavutil/ffmath.h"
#include "libavutil/opt.h"
#include "libavutil/samplefmt.h"
#include "audio.h"
#include "avfilter.h"
#include "internal.h"

Go to the source code of this file.

Data Structures
struct	ChanParam
struct	CompandSegment
struct	CompandContext

Macros
#define	OFFSET(x)   offsetof(CompandContext, x)
#define	A   AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
#define	MOD(a, b)   (((a) >= (b)) ? (a) - (b) : (a))
#define	S(x)   s->segments[2 * ((x) + 1)]
#define	S(x)   s->segments[2 * (x)]
#define	L(x)   s->segments[i - (x)]

Functions
	AVFILTER_DEFINE_CLASS (compand)
static av_cold int	init (AVFilterContext *ctx)
static av_cold void	uninit (AVFilterContext *ctx)
static int	query_formats (AVFilterContext *ctx)
static void	count_items (char *item_str, int *nb_items)
static void	update_volume (ChanParam *cp, double in)
static double	get_volume (CompandContext *s, double in_lin)
static int	compand_nodelay (AVFilterContext *ctx, AVFrame *frame)
static int	compand_delay (AVFilterContext *ctx, AVFrame *frame)
static int	compand_drain (AVFilterLink *outlink)
static int	config_output (AVFilterLink *outlink)
static int	filter_frame (AVFilterLink *inlink, AVFrame *frame)
static int	request_frame (AVFilterLink *outlink)

Variables
static const AVOption	compand_options []
static const AVFilterPad	compand_inputs []
static const AVFilterPad	compand_outputs []
AVFilter	ff_af_compand

Detailed Description

audio compand filter

Definition in file af_compand.c.

Macro Definition Documentation

#define OFFSET

(

x

)

offsetof(CompandContext, x)

Definition at line 71 of file af_compand.c.

#define A   AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM

Definition at line 72 of file af_compand.c.

#define MOD	(		a,
			b
	)		(((a) >= (b)) ? (a) - (b) : (a))

Definition at line 219 of file af_compand.c.

Referenced by compand_delay().

#define S

(

x

)

s->segments[2 * ((x) + 1)]

Referenced by config_output().

#define S

(

x

)

s->segments[2 * (x)]

#define L

(

x

)

s->segments[i - (x)]

Referenced by config_output().

Function Documentation

AVFILTER_DEFINE_CLASS

(

compand

)

static av_cold int init ( AVFilterContext *  ctx )

static

Definition at line 87 of file af_compand.c.

static av_cold void uninit ( AVFilterContext *  ctx )

static

Definition at line 94 of file af_compand.c.

Referenced by config_output().

static int query_formats ( AVFilterContext *  ctx )

static

Definition at line 103 of file af_compand.c.

static void count_items ( char *  item_str, int *  nb_items  )

static

Definition at line 133 of file af_compand.c.

Referenced by config_output().

static void update_volume ( ChanParam *  cp, double  in  )

static

Definition at line 144 of file af_compand.c.

Referenced by compand_delay(), and compand_nodelay().

static double get_volume ( CompandContext *  s, double  in_lin  )

static

Definition at line 154 of file af_compand.c.

Referenced by compand_delay(), and compand_nodelay().

static int compand_nodelay ( AVFilterContext *  ctx, AVFrame *  frame  )

static

Definition at line 175 of file af_compand.c.

Referenced by config_output().

static int compand_delay ( AVFilterContext *  ctx, AVFrame *  frame  )

static

Definition at line 221 of file af_compand.c.

Referenced by config_output().

static int compand_drain ( AVFilterLink *  outlink )

static

Definition at line 293 of file af_compand.c.

Referenced by request_frame().

static int config_output ( AVFilterLink *  outlink )

static

Definition at line 328 of file af_compand.c.

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

static

Definition at line 545 of file af_compand.c.

static int request_frame ( AVFilterLink *  outlink )

static

Definition at line 553 of file af_compand.c.

Variable Documentation

const AVOption compand_options[]

static

Initial value:

= {
    { "attacks", "set time over which increase of volume is determined", OFFSET(attacks), AV_OPT_TYPE_STRING, { .str = "0" }, 0, 0, A },
    { "decays", "set time over which decrease of volume is determined", OFFSET(decays), AV_OPT_TYPE_STRING, { .str = "0.8" }, 0, 0, A },
    { "points", "set points of transfer function", OFFSET(points), AV_OPT_TYPE_STRING, { .str = "-70/-70|-60/-20|1/0" }, 0, 0, A },
    { "soft-knee", "set soft-knee", OFFSET(curve_dB), AV_OPT_TYPE_DOUBLE, { .dbl = 0.01 }, 0.01, 900, A },
    { "gain", "set output gain", OFFSET(gain_dB), AV_OPT_TYPE_DOUBLE, { .dbl = 0 }, -900, 900, A },
    { "volume", "set initial volume", OFFSET(initial_volume), AV_OPT_TYPE_DOUBLE, { .dbl = 0 }, -900, 0, A },
    { "delay", "set delay for samples before sending them to volume adjuster", OFFSET(delay), AV_OPT_TYPE_DOUBLE, { .dbl = 0 }, 0, 20, A },
    { NULL }
}

Definition at line 74 of file af_compand.c.

const AVFilterPad compand_inputs[]

static

Initial value:

= {
    {
        .name         = "default",
        .type         = AVMEDIA_TYPE_AUDIO,
        .filter_frame = filter_frame,
    },
    { NULL }
}

Definition at line 567 of file af_compand.c.

const AVFilterPad compand_outputs[]

static

Initial value:

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

Definition at line 576 of file af_compand.c.

AVFilter ff_af_compand

Initial value:

= {
    .name           = "compand",
    .description    = NULL_IF_CONFIG_SMALL(
            "Compress or expand audio dynamic range."),
    .query_formats  = query_formats,
    .priv_size      = sizeof(CompandContext),
    .priv_class     = &compand_class,
    .init           = init,
    .uninit         = uninit,
    .inputs         = compand_inputs,
    .outputs        = compand_outputs,
}

Definition at line 587 of file af_compand.c.