libavcodec/resample2.c File Reference

audio resampling More...

#include "libavutil/avassert.h"
#include "avcodec.h"
#include "dsputil.h"
#include "libavutil/common.h"

Go to the source code of this file.

Data Structures
struct	AVResampleContext
Defines
#define	FILTER_SHIFT   15
#define	FELEM   int16_t
#define	FELEM2   int32_t
#define	FELEML   int64_t
#define	FELEM_MAX   INT16_MAX
#define	FELEM_MIN   INT16_MIN
#define	WINDOW_TYPE   9
Functions
static double	bessel (double x)
	0th order modified bessel function of the first kind.
static int	build_filter (FELEM *filter, double factor, int tap_count, int phase_count, int scale, int type)
	Build a polyphase filterbank.
AVResampleContext *	av_resample_init (int out_rate, int in_rate, int filter_size, int phase_shift, int linear, double cutoff)
	Initialize an audio resampler.
void	av_resample_close (AVResampleContext *c)
void	av_resample_compensate (AVResampleContext *c, int sample_delta, int compensation_distance)
	Compensate samplerate/timestamp drift.
int	av_resample (AVResampleContext *c, short *dst, short *src, int *consumed, int src_size, int dst_size, int update_ctx)
	Resample an array of samples using a previously configured context.

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Detailed Description

audio resampling

Author:

Michael Niedermayer <michaelni@gmx.at>

Definition in file resample2.c.

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Define Documentation

#define FELEM   int16_t

Definition at line 36 of file resample2.c.

Referenced by av_resample(), av_resample_init(), resample_one(), set_filter(), and swri_resample_TMPL().

#define FELEM2   int32_t

Definition at line 37 of file resample2.c.

Referenced by av_resample(), resample_one(), and swri_resample_TMPL().

#define FELEM_MAX   INT16_MAX

Definition at line 39 of file resample2.c.

Referenced by build_filter().

#define FELEM_MIN   INT16_MIN

Definition at line 40 of file resample2.c.

Referenced by build_filter().

#define FELEML   int64_t

Definition at line 38 of file resample2.c.

Referenced by av_resample(), resample_one(), and swri_resample_TMPL().

#define FILTER_SHIFT   15

Definition at line 34 of file resample2.c.

Referenced by av_resample(), av_resample_init(), build_filter(), and swri_resample_TMPL().

#define WINDOW_TYPE   9

Definition at line 41 of file resample2.c.

Referenced by av_resample_init().

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Function Documentation

static double bessel

(

double

x

)

[static]

0th order modified bessel function of the first kind.

Definition at line 79 of file resample2.c.

Referenced by build_filter(), and ff_kbd_window_init().

static int build_filter	(	FELEM *	filter,
		double	factor,
		int	tap_count,
		int	phase_count,
		int	scale,
		int	type
	)			[static]

Build a polyphase filterbank.

Parameters:

	factor	resampling factor
	scale	wanted sum of coefficients for each filter
	type	0->cubic, 1->blackman nuttall windowed sinc, 2..16->kaiser windowed sinc beta=2..16

Returns:

0 on success, negative on error

Definition at line 101 of file resample2.c.

Referenced by av_resample_init(), ff_audio_resample_init(), and swri_resample_init().