af_axcorrelate.c File Reference

#include "libavutil/audio_fifo.h"
#include "libavutil/channel_layout.h"
#include "libavutil/common.h"
#include "libavutil/opt.h"
#include "audio.h"
#include "avfilter.h"
#include "filters.h"
#include "internal.h"

Go to the source code of this file.

Data Structures
struct	AudioXCorrelateContext

Macros
#define	MEAN_SUM(suffix, type, zero)
#define	SQUARE_SUM(suffix, type, zero)
#define	XCORRELATE(suffix, type, zero, small, sqrtfun)
#define	XCORRELATE_SLOW(suffix, type)
#define	clipf(x)   (av_clipf(x, -1.f, 1.f))
#define	clipd(x)   (av_clipd(x, -1.0, 1.0))
#define	XCORRELATE_FAST(suffix, type, zero, small, sqrtfun, CLIP)
#define	XCORRELATE_BEST(suffix, type, zero, small, sqrtfun, FMAX, CLIP)
#define	AF   AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
#define	OFFSET(x)   offsetof(AudioXCorrelateContext, x)

Functions
static int	activate (AVFilterContext *ctx)
static int	config_output (AVFilterLink *outlink)
static av_cold void	uninit (AVFilterContext *ctx)
	AVFILTER_DEFINE_CLASS (axcorrelate)

Variables
static const AVFilterPad	inputs []
static const AVFilterPad	outputs []
static const AVOption	axcorrelate_options []
const AVFilter	ff_af_axcorrelate

Macro Definition Documentation

MEAN_SUM

#define MEAN_SUM	(		suffix,
			type,
			zero
	)

Value:

static type mean_sum_##suffix(const type *in,  \
                              int size)        \
{                                              \
    type mean_sum = zero;                      \
                                               \
    for (int i = 0; i < size; i++)             \
        mean_sum += in[i];                     \
                                               \
    return mean_sum;                           \
}

Definition at line 49 of file af_axcorrelate.c.

SQUARE_SUM

#define SQUARE_SUM	(		suffix,
			type,
			zero
	)

Value:

static type square_sum_##suffix(const type *x, \
                        const type *y,         \
                        int size)              \
{                                              \
    type square_sum = zero;                    \
                                               \
    for (int i = 0; i < size; i++)             \
        square_sum += x[i] * y[i];             \
                                               \
    return square_sum;                         \
}

Definition at line 64 of file af_axcorrelate.c.

XCORRELATE

#define XCORRELATE	(		suffix,
			type,
			zero,
			small,
			sqrtfun
	)

Value:

static type xcorrelate_##suffix(const type *x,       \
                                const type *y,       \
                                type sumx,           \
                                type sumy, int size) \
{                                                    \
    const type xm = sumx / size, ym = sumy / size;   \
    type num = zero, den, den0 = zero, den1 = zero;  \
                                                     \
    for (int i = 0; i < size; i++) {                 \
        type xd = x[i] - xm;                         \
        type yd = y[i] - ym;                         \
                                                     \
        num += xd * yd;                              \
        den0 += xd * xd;                             \
        den1 += yd * yd;                             \
    }                                                \
                                                     \
    num /= size;                                     \
    den  = sqrtfun((den0 * den1) / size / size);     \
                                                     \
    return den <= small ? zero : num / den;          \
}

Definition at line 80 of file af_axcorrelate.c.

XCORRELATE_SLOW

#define XCORRELATE_SLOW	(		suffix,
			type
	)

Definition at line 107 of file af_axcorrelate.c.

clipf

#define clipf

(

x

)

(av_clipf(x, -1.f, 1.f))

Definition at line 149 of file af_axcorrelate.c.

clipd

#define clipd

(

x

)

(av_clipd(x, -1.0, 1.0))

Definition at line 150 of file af_axcorrelate.c.

XCORRELATE_FAST

#define XCORRELATE_FAST	(		suffix,
			type,
			zero,
			small,
			sqrtfun,
			CLIP
	)

Definition at line 152 of file af_axcorrelate.c.

XCORRELATE_BEST

#define XCORRELATE_BEST	(		suffix,
			type,
			zero,
			small,
			sqrtfun,
			FMAX,
			CLIP
	)

Definition at line 202 of file af_axcorrelate.c.

AF

#define AF   AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM

Definition at line 444 of file af_axcorrelate.c.

OFFSET

#define OFFSET

(

x

)

offsetof(AudioXCorrelateContext, x)

Definition at line 445 of file af_axcorrelate.c.

Function Documentation

activate()

static int activate ( AVFilterContext *  ctx )

static

Definition at line 263 of file af_axcorrelate.c.

config_output()

static int config_output ( AVFilterLink *  outlink )

static

Definition at line 372 of file af_axcorrelate.c.

uninit()

static av_cold void uninit ( AVFilterContext *  ctx )

static

Definition at line 410 of file af_axcorrelate.c.

AVFILTER_DEFINE_CLASS()

AVFILTER_DEFINE_CLASS

(

axcorrelate

)

Variable Documentation

inputs

const AVFilterPad inputs[]

static

Initial value:

= {
    {
        .name = "axcorrelate0",
        .type = AVMEDIA_TYPE_AUDIO,
    },
    {
        .name = "axcorrelate1",
        .type = AVMEDIA_TYPE_AUDIO,
    },
}

Definition at line 425 of file af_axcorrelate.c.

outputs

const AVFilterPad outputs[]

static

Initial value:

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

Definition at line 436 of file af_axcorrelate.c.

axcorrelate_options

const AVOption axcorrelate_options[]

static

Initial value:

= {
    { "size", "set the segment size", OFFSET(size), AV_OPT_TYPE_INT, {.i64=256}, 2, 131072, AF },
    { "algo", "set the algorithm",    OFFSET(algo), AV_OPT_TYPE_INT, {.i64=2},   0,      2, AF, .unit = "algo" },
    { "slow", "slow algorithm",   0,            AV_OPT_TYPE_CONST, {.i64=0},   0,      0, AF, .unit = "algo" },
    { "fast", "fast algorithm",   0,            AV_OPT_TYPE_CONST, {.i64=1},   0,      0, AF, .unit = "algo" },
    { "best", "best algorithm",   0,            AV_OPT_TYPE_CONST, {.i64=2},   0,      0, AF, .unit = "algo" },
    { NULL }
}

Definition at line 447 of file af_axcorrelate.c.

ff_af_axcorrelate

const AVFilter ff_af_axcorrelate

Initial value:

= {
    .name           = "axcorrelate",
    .description    = NULL_IF_CONFIG_SMALL("Cross-correlate two audio streams."),
    .priv_size      = sizeof(AudioXCorrelateContext),
    .priv_class     = &axcorrelate_class,
    .activate       = activate,
    .uninit         = uninit,
    FILTER_INPUTS(inputs),
    FILTER_OUTPUTS(outputs),
    FILTER_SAMPLEFMTS(AV_SAMPLE_FMT_FLTP, AV_SAMPLE_FMT_DBLP),
}

Definition at line 458 of file af_axcorrelate.c.