SwrContext Struct Reference

The libswresample context. More...

#include <swresample_internal.h>

Data Fields
const AVClass *	av_class
	AVClass used for AVOption and av_log()
int	log_level_offset
	logging level offset
void *	log_ctx
	parent logging context
enum AVSampleFormat	in_sample_fmt
	input sample format
enum AVSampleFormat	int_sample_fmt
	internal sample format (AV_SAMPLE_FMT_FLTP or AV_SAMPLE_FMT_S16P)
enum AVSampleFormat	out_sample_fmt
	output sample format
int64_t	in_ch_layout
	input channel layout
int64_t	out_ch_layout
	output channel layout
int	in_sample_rate
	input sample rate
int	out_sample_rate
	output sample rate
int	flags
	miscellaneous flags such as SWR_FLAG_RESAMPLE
float	slev
	surround mixing level
float	clev
	center mixing level
float	lfe_mix_level
	LFE mixing level.
float	rematrix_volume
	rematrixing volume coefficient
float	rematrix_maxval
	maximum value for rematrixing output
int	matrix_encoding
	matrixed stereo encoding
const int *	channel_map
	channel index (or -1 if muted channel) map
int	used_ch_count
	number of used input channels (mapped channel count if channel_map, otherwise in.ch_count)
int	engine
struct DitherContext	dither
int	filter_size
	length of each FIR filter in the resampling filterbank relative to the cutoff frequency
int	phase_shift
	log2 of the number of entries in the resampling polyphase filterbank
int	linear_interp
	if 1 then the resampling FIR filter will be linearly interpolated
double	cutoff
	resampling cutoff frequency (swr: 6dB point; soxr: 0dB point).
int	filter_type
	swr resampling filter type
int	kaiser_beta
	swr beta value for Kaiser window (only applicable if filter_type == AV_FILTER_TYPE_KAISER)
double	precision
	soxr resampling precision (in bits)
int	cheby
	soxr: if 1 then passband rolloff will be none (Chebyshev) & irrational ratio approximation precision will be higher
float	min_compensation
	swr minimum below which no compensation will happen
float	min_hard_compensation
	swr minimum below which no silence inject / sample drop will happen
float	soft_compensation_duration
	swr duration over which soft compensation is applied
float	max_soft_compensation
	swr maximum soft compensation in seconds over soft_compensation_duration
float	async
	swr simple 1 parameter async, similar to ffmpegs -async
int64_t	firstpts_in_samples
	swr first pts in samples
int	resample_first
	1 if resampling must come first, 0 if rematrixing
int	rematrix
	flag to indicate if rematrixing is needed (basically if input and output layouts mismatch)
int	rematrix_custom
	flag to indicate that a custom matrix has been defined
AudioData	in
	input audio data
AudioData	postin
	post-input audio data: used for rematrix/resample
AudioData	midbuf
	intermediate audio data (postin/preout)
AudioData	preout
	pre-output audio data: used for rematrix/resample
AudioData	out
	converted output audio data
AudioData	in_buffer
	cached audio data (convert and resample purpose)
AudioData	silence
	temporary with silence
AudioData	drop_temp
	temporary used to discard output
int	in_buffer_index
	cached buffer position
int	in_buffer_count
	cached buffer length
int	resample_in_constraint
	1 if the input end was reach before the output end, 0 otherwise
int	flushed
	1 if data is to be flushed and no further input is expected
int64_t	outpts
	output PTS
int64_t	firstpts
	first PTS
int	drop_output
	number of output samples to drop
struct AudioConvert *	in_convert
	input conversion context
struct AudioConvert *	out_convert
	output conversion context
struct AudioConvert *	full_convert
	full conversion context (single conversion for input and output)
struct ResampleContext *	resample
	resampling context
struct Resampler const *	resampler
	resampler virtual function table
float	matrix [SWR_CH_MAX][SWR_CH_MAX]
	floating point rematrixing coefficients
uint8_t *	native_matrix
uint8_t *	native_one
uint8_t *	native_simd_one
uint8_t *	native_simd_matrix
int32_t	matrix32 [SWR_CH_MAX][SWR_CH_MAX]
	17.15 fixed point rematrixing coefficients
uint8_t	matrix_ch [SWR_CH_MAX][SWR_CH_MAX+1]
	Lists of input channels per output channel that have non zero rematrixing coefficients.
mix_1_1_func_type *	mix_1_1_f
mix_1_1_func_type *	mix_1_1_simd
mix_2_1_func_type *	mix_2_1_f
mix_2_1_func_type *	mix_2_1_simd
mix_any_func_type *	mix_any_f

Detailed Description

The libswresample context.

Unlike libavcodec and libavformat, this structure is opaque. This means that if you would like to set options, you must use the AVOptions API and cannot directly set values to members of the structure.

Examples:

muxing.c, resampling_audio.c, and transcode_aac.c.

Definition at line 93 of file swresample_internal.h.

Field Documentation

const AVClass* SwrContext::av_class

AVClass used for AVOption and av_log()

Definition at line 94 of file swresample_internal.h.

Referenced by swr_alloc().

int SwrContext::log_level_offset

logging level offset

Definition at line 95 of file swresample_internal.h.

Referenced by swr_alloc_set_opts().

void* SwrContext::log_ctx

parent logging context

Definition at line 96 of file swresample_internal.h.

Referenced by swr_alloc_set_opts().

enum AVSampleFormat SwrContext::in_sample_fmt

input sample format

Definition at line 97 of file swresample_internal.h.

Referenced by config_changed(), main(), swr_convert_internal(), and swr_init().

enum AVSampleFormat SwrContext::int_sample_fmt

internal sample format (AV_SAMPLE_FMT_FLTP or AV_SAMPLE_FMT_S16P)

Definition at line 98 of file swresample_internal.h.

Referenced by auto_matrix(), swr_convert_internal(), swr_init(), and swri_rematrix().

enum AVSampleFormat SwrContext::out_sample_fmt

output sample format

Definition at line 99 of file swresample_internal.h.

Referenced by auto_matrix(), config_changed(), swr_convert_internal(), and swr_init().

int64_t SwrContext::in_ch_layout

input channel layout

Definition at line 100 of file swresample_internal.h.

Referenced by auto_matrix(), config_changed(), swr_init(), swr_set_matrix(), and swri_rematrix_init().

int64_t SwrContext::out_ch_layout

output channel layout

Definition at line 101 of file swresample_internal.h.

Referenced by auto_matrix(), config_changed(), swr_alloc_set_opts(), swr_init(), swr_set_matrix(), swri_rematrix(), and swri_rematrix_init().

int SwrContext::in_sample_rate

input sample rate

Definition at line 102 of file swresample_internal.h.

Referenced by config_changed(), get_delay(), swr_convert(), swr_convert_frame(), swr_get_delay(), swr_init(), and swr_next_pts().

int SwrContext::out_sample_rate

output sample rate

Definition at line 103 of file swresample_internal.h.

Referenced by config_changed(), get_delay(), swr_convert_frame(), swr_init(), swr_next_pts(), and swri_dither_init().

int SwrContext::flags

miscellaneous flags such as SWR_FLAG_RESAMPLE

Definition at line 104 of file swresample_internal.h.

Referenced by swr_init(), and swr_set_compensation().

float SwrContext::slev

surround mixing level

Definition at line 105 of file swresample_internal.h.

Referenced by auto_matrix().

float SwrContext::clev

center mixing level

Definition at line 106 of file swresample_internal.h.

Referenced by auto_matrix().

float SwrContext::lfe_mix_level

LFE mixing level.

Definition at line 107 of file swresample_internal.h.

Referenced by auto_matrix().

float SwrContext::rematrix_volume

rematrixing volume coefficient

Definition at line 108 of file swresample_internal.h.

Referenced by auto_matrix(), and swr_init().

float SwrContext::rematrix_maxval

maximum value for rematrixing output

Definition at line 109 of file swresample_internal.h.

Referenced by auto_matrix().

int SwrContext::matrix_encoding

matrixed stereo encoding

Definition at line 110 of file swresample_internal.h.

Referenced by auto_matrix().

const int* SwrContext::channel_map

channel index (or -1 if muted channel) map

Definition at line 111 of file swresample_internal.h.

Referenced by ff_opus_parse_extradata(), swr_convert_internal(), swr_init(), and swr_set_channel_mapping().

int SwrContext::used_ch_count

number of used input channels (mapped channel count if channel_map, otherwise in.ch_count)

Definition at line 112 of file swresample_internal.h.

Referenced by swr_convert_internal(), and swr_init().

int SwrContext::engine

Definition at line 113 of file swresample_internal.h.

Referenced by resample(), and swr_init().

struct DitherContext SwrContext::dither

Definition at line 115 of file swresample_internal.h.

Referenced by clear_context(), swr_convert_internal(), swr_init(), swri_dither_init(), and swri_get_dither().

int SwrContext::filter_size

length of each FIR filter in the resampling filterbank relative to the cutoff frequency

Definition at line 117 of file swresample_internal.h.

Referenced by swr_init().

int SwrContext::phase_shift

log2 of the number of entries in the resampling polyphase filterbank

Definition at line 118 of file swresample_internal.h.

Referenced by swr_init().

int SwrContext::linear_interp

if 1 then the resampling FIR filter will be linearly interpolated

Definition at line 119 of file swresample_internal.h.

Referenced by swr_init().

double SwrContext::cutoff

resampling cutoff frequency (swr: 6dB point; soxr: 0dB point).

1.0 corresponds to half the output sample rate

Definition at line 120 of file swresample_internal.h.

Referenced by swr_init().

int SwrContext::filter_type

swr resampling filter type

Definition at line 121 of file swresample_internal.h.

Referenced by swr_init().

int SwrContext::kaiser_beta

swr beta value for Kaiser window (only applicable if filter_type == AV_FILTER_TYPE_KAISER)

Definition at line 122 of file swresample_internal.h.

Referenced by swr_init().

double SwrContext::precision

soxr resampling precision (in bits)

Definition at line 123 of file swresample_internal.h.

Referenced by swr_init().

int SwrContext::cheby

soxr: if 1 then passband rolloff will be none (Chebyshev) & irrational ratio approximation precision will be higher

Definition at line 124 of file swresample_internal.h.

Referenced by swr_init().

float SwrContext::min_compensation

swr minimum below which no compensation will happen

Definition at line 126 of file swresample_internal.h.

Referenced by swr_init(), and swr_next_pts().

float SwrContext::min_hard_compensation

swr minimum below which no silence inject / sample drop will happen

Definition at line 127 of file swresample_internal.h.

Referenced by swr_next_pts().

float SwrContext::soft_compensation_duration

swr duration over which soft compensation is applied

Definition at line 128 of file swresample_internal.h.

Referenced by swr_next_pts().

float SwrContext::max_soft_compensation

swr maximum soft compensation in seconds over soft_compensation_duration

Definition at line 129 of file swresample_internal.h.

Referenced by swr_init(), and swr_next_pts().

float SwrContext::async

swr simple 1 parameter async, similar to ffmpegs -async

Definition at line 130 of file swresample_internal.h.

Referenced by swr_init().

int64_t SwrContext::firstpts_in_samples

swr first pts in samples

Definition at line 131 of file swresample_internal.h.

Referenced by swr_init().

int SwrContext::resample_first

1 if resampling must come first, 0 if rematrixing

Definition at line 133 of file swresample_internal.h.

Referenced by swr_convert_internal(), and swr_init().

int SwrContext::rematrix

flag to indicate if rematrixing is needed (basically if input and output layouts mismatch)

Definition at line 134 of file swresample_internal.h.

Referenced by swr_convert_internal(), and swr_init().

int SwrContext::rematrix_custom

flag to indicate that a custom matrix has been defined

Definition at line 135 of file swresample_internal.h.

Referenced by swr_init(), swr_set_matrix(), and swri_rematrix_init().

AudioData SwrContext::in

input audio data

Definition at line 137 of file swresample_internal.h.

Referenced by clear_context(), swr_convert(), swr_convert_internal(), and swr_init().

AudioData SwrContext::postin

post-input audio data: used for rematrix/resample

Definition at line 138 of file swresample_internal.h.

Referenced by clear_context(), swr_convert_internal(), and swr_init().

AudioData SwrContext::midbuf

intermediate audio data (postin/preout)

Definition at line 139 of file swresample_internal.h.

Referenced by clear_context(), swr_convert_internal(), swr_init(), and swri_rematrix_init().

AudioData SwrContext::preout

pre-output audio data: used for rematrix/resample

Definition at line 140 of file swresample_internal.h.

Referenced by clear_context(), swr_convert_internal(), swr_init(), and swri_dither_init().

AudioData SwrContext::out

converted output audio data

Definition at line 141 of file swresample_internal.h.

Referenced by clear_context(), swr_convert(), swr_convert_internal(), and swr_init().

AudioData SwrContext::in_buffer

cached audio data (convert and resample purpose)

Definition at line 142 of file swresample_internal.h.

Referenced by clear_context(), resample(), resample_flush(), swr_convert(), swr_init(), and swr_is_initialized().

AudioData SwrContext::silence

temporary with silence

Definition at line 143 of file swresample_internal.h.

Referenced by clear_context(), swr_init(), and swr_inject_silence().

AudioData SwrContext::drop_temp

temporary used to discard output

Definition at line 144 of file swresample_internal.h.

Referenced by clear_context(), swr_convert(), and swr_init().

int SwrContext::in_buffer_index

cached buffer position

Definition at line 145 of file swresample_internal.h.

Referenced by clear_context(), resample(), resample_flush(), and swr_convert().

int SwrContext::in_buffer_count

cached buffer length

Definition at line 146 of file swresample_internal.h.

Referenced by clear_context(), get_delay(), resample(), resample_flush(), swr_convert(), and swr_get_delay().

int SwrContext::resample_in_constraint

1 if the input end was reach before the output end, 0 otherwise

Definition at line 147 of file swresample_internal.h.

Referenced by clear_context(), resample(), and swr_convert().

int SwrContext::flushed

1 if data is to be flushed and no further input is expected

Definition at line 148 of file swresample_internal.h.

Referenced by clear_context(), resample(), and swr_convert().

int64_t SwrContext::outpts

output PTS

Definition at line 149 of file swresample_internal.h.

Referenced by filter_frame(), swr_convert(), swr_init(), and swr_next_pts().

int64_t SwrContext::firstpts

first PTS

Definition at line 150 of file swresample_internal.h.

Referenced by swr_init(), and swr_next_pts().

int SwrContext::drop_output

number of output samples to drop

Definition at line 151 of file swresample_internal.h.

Referenced by swr_convert(), swr_drop_output(), and swr_next_pts().

struct AudioConvert* SwrContext::in_convert

input conversion context

Definition at line 153 of file swresample_internal.h.

Referenced by clear_context(), swr_convert_internal(), swr_init(), swr_set_channel_mapping(), and swr_set_matrix().

struct AudioConvert* SwrContext::out_convert

output conversion context

Definition at line 154 of file swresample_internal.h.

Referenced by clear_context(), swr_convert_internal(), and swr_init().

struct AudioConvert* SwrContext::full_convert

full conversion context (single conversion for input and output)

Definition at line 155 of file swresample_internal.h.

Referenced by clear_context(), swr_convert_internal(), and swr_init().

struct ResampleContext* SwrContext::resample

resampling context

Definition at line 156 of file swresample_internal.h.

Referenced by flush(), get_delay(), resample(), swr_convert(), swr_convert_internal(), swr_free(), swr_get_delay(), swr_init(), and swr_set_compensation().

struct Resampler const* SwrContext::resampler

resampler virtual function table

Definition at line 157 of file swresample_internal.h.

Referenced by resample(), swr_convert(), swr_free(), swr_get_delay(), swr_init(), and swr_set_compensation().

float SwrContext::matrix[SWR_CH_MAX][SWR_CH_MAX]

floating point rematrixing coefficients

Definition at line 159 of file swresample_internal.h.

Referenced by auto_matrix(), swr_set_matrix(), swri_rematrix(), and swri_rematrix_init().

uint8_t* SwrContext::native_matrix

Definition at line 160 of file swresample_internal.h.

Referenced by swri_rematrix(), swri_rematrix_free(), and swri_rematrix_init().

uint8_t* SwrContext::native_one

Definition at line 161 of file swresample_internal.h.

Referenced by swr_convert_internal(), swri_rematrix_free(), and swri_rematrix_init().

uint8_t* SwrContext::native_simd_one

Definition at line 162 of file swresample_internal.h.

Referenced by swr_convert_internal(), and swri_rematrix_free().

uint8_t* SwrContext::native_simd_matrix

Definition at line 163 of file swresample_internal.h.

Referenced by swri_rematrix(), and swri_rematrix_free().

int32_t SwrContext::matrix32[SWR_CH_MAX][SWR_CH_MAX]

17.15 fixed point rematrixing coefficients

Definition at line 164 of file swresample_internal.h.

Referenced by swri_rematrix(), and swri_rematrix_init().

uint8_t SwrContext::matrix_ch[SWR_CH_MAX][SWR_CH_MAX+1]

Lists of input channels per output channel that have non zero rematrixing coefficients.

Definition at line 165 of file swresample_internal.h.

Referenced by swri_rematrix(), and swri_rematrix_init().

mix_1_1_func_type* SwrContext::mix_1_1_f

Definition at line 166 of file swresample_internal.h.

Referenced by swri_rematrix(), and swri_rematrix_init().

mix_1_1_func_type* SwrContext::mix_1_1_simd

Definition at line 167 of file swresample_internal.h.

Referenced by swri_rematrix().

mix_2_1_func_type* SwrContext::mix_2_1_f

Definition at line 169 of file swresample_internal.h.

Referenced by swr_convert_internal(), swri_rematrix(), and swri_rematrix_init().

mix_2_1_func_type* SwrContext::mix_2_1_simd

Definition at line 170 of file swresample_internal.h.

Referenced by swr_convert_internal(), and swri_rematrix().

mix_any_func_type* SwrContext::mix_any_f

Definition at line 172 of file swresample_internal.h.

Referenced by swri_rematrix(), and swri_rematrix_init().

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The documentation for this struct was generated from the following file:

• libswresample/swresample_internal.h