resample.c File Reference

samplerate conversion for both audio and video More...

#include "avcodec.h"
#include "audioconvert.h"
#include "libavutil/opt.h"
#include "libavutil/samplefmt.h"

Go to the source code of this file.

Data Structures
struct	ReSampleContext

Macros
#define	MAX_CHANNELS   8

Functions
static const char *	context_to_name (void *ptr)
static void	stereo_to_mono (short *output, short *input, int n1)
static void	mono_to_stereo (short *output, short *input, int n1)
static void	deinterleave (short **output, short *input, int channels, int samples)
static void	interleave (short *output, short **input, int channels, int samples)
static void	ac3_5p1_mux (short *output, short *input1, short *input2, int n)
ReSampleContext *	av_audio_resample_init (int output_channels, int input_channels, int output_rate, int input_rate, enum AVSampleFormat sample_fmt_out, enum AVSampleFormat sample_fmt_in, int filter_length, int log2_phase_count, int linear, double cutoff)
	Initialize audio resampling context.
int	audio_resample (ReSampleContext *s, short *output, short *input, int nb_samples)
void	audio_resample_close (ReSampleContext *s)
	Free resample context.

Variables
static const AVOption	options [] = {{NULL}}
static const AVClass	audioresample_context_class

Detailed Description

samplerate conversion for both audio and video

Definition in file resample.c.

Macro Definition Documentation

#define MAX_CHANNELS   8

Definition at line 32 of file resample.c.

Referenced by audio_resample(), and av_audio_resample_init().

Function Documentation

static void ac3_5p1_mux ( short *  output, short *  input1, short *  input2, int  n  )

static

Definition at line 133 of file resample.c.

Referenced by audio_resample().

int audio_resample	(	ReSampleContext *	s,
		short *	output,
		short *	input,
		int	nb_samples
	)

Definition at line 228 of file resample.c.

Referenced by do_audio_out().

void audio_resample_close

(

ReSampleContext *

s

)

Free resample context.

Parameters

s	a non-NULL pointer to a resample context previously created with av_audio_resample_init()

Definition at line 359 of file resample.c.

Referenced by do_audio_out(), and transcode().

ReSampleContext* av_audio_resample_init	(	int	output_channels,
		int	input_channels,
		int	output_rate,
		int	input_rate,
		enum AVSampleFormat	sample_fmt_out,
		enum AVSampleFormat	sample_fmt_in,
		int	filter_length,
		int	log2_phase_count,
		int	linear,
		double	cutoff
	)

Initialize audio resampling context.

Parameters

output_channels	number of output channels
input_channels	number of input channels
output_rate	output sample rate
input_rate	input sample rate
sample_fmt_out	requested output sample format
sample_fmt_in	input sample format
filter_length	length of each FIR filter in the filterbank relative to the cutoff frequency
log2_phase_count	log2 of the number of entries in the polyphase filterbank
linear	if 1 then the used FIR filter will be linearly interpolated between the 2 closest, if 0 the closest will be used
cutoff	cutoff frequency, 1.0 corresponds to half the output sampling rate

Returns

allocated ReSampleContext, NULL if error occurred

Definition at line 150 of file resample.c.

Referenced by do_audio_out().

static const char* context_to_name ( void *  ptr )

static

Definition at line 36 of file resample.c.

static void deinterleave ( short **  output, short *  input, int  channels, int  samples  )

static

Definition at line 111 of file resample.c.

Referenced by audio_resample().

static void interleave ( short *  output, short **  input, int  channels, int  samples  )

static

Definition at line 122 of file resample.c.

Referenced by audio_resample().

static void mono_to_stereo ( short *  output, short *  input, int  n1  )

static

Definition at line 86 of file resample.c.

Referenced by audio_resample().

static void stereo_to_mono ( short *  output, short *  input, int  n1  )

static

Definition at line 61 of file resample.c.

Referenced by audio_resample().

Variable Documentation

const AVClass audioresample_context_class

static

Initial value:

 {
    "ReSampleContext", context_to_name, options, LIBAVUTIL_VERSION_INT
}

Definition at line 42 of file resample.c.

const AVOption options[] = {{NULL}}

static

Definition at line 41 of file resample.c.