Audio related
[Common utility functions]


Modules
	Audio channel masks
	Audio channel convenience macros
Typedefs
typedef struct AVAudioFifo	AVAudioFifo
	Context for an Audio FIFO Buffer.
Functions
void	av_audio_fifo_free (AVAudioFifo *af)
	Free an AVAudioFifo.
AVAudioFifo *	av_audio_fifo_alloc (enum AVSampleFormat sample_fmt, int channels, int nb_samples)
	Allocate an AVAudioFifo.
int	av_audio_fifo_realloc (AVAudioFifo *af, int nb_samples)
	Reallocate an AVAudioFifo.
int	av_audio_fifo_write (AVAudioFifo af, void *data, int nb_samples)
	Write data to an AVAudioFifo.
int	av_audio_fifo_read (AVAudioFifo af, void *data, int nb_samples)
	Read data from an AVAudioFifo.
int	av_audio_fifo_drain (AVAudioFifo *af, int nb_samples)
	Drain data from an AVAudioFifo.
void	av_audio_fifo_reset (AVAudioFifo *af)
	Reset the AVAudioFifo buffer.
int	av_audio_fifo_size (AVAudioFifo *af)
	Get the current number of samples in the AVAudioFifo available for reading.
int	av_audio_fifo_space (AVAudioFifo *af)
	Get the current number of samples in the AVAudioFifo available for writing.
uint64_t	av_get_channel_layout (const char *name)
	Return a channel layout id that matches name, or 0 if no match is found.
void	av_get_channel_layout_string (char *buf, int buf_size, int nb_channels, uint64_t channel_layout)
	Return a description of a channel layout.
void	av_bprint_channel_layout (struct AVBPrint *bp, int nb_channels, uint64_t channel_layout)
	Append a description of a channel layout to a bprint buffer.
int	av_get_channel_layout_nb_channels (uint64_t channel_layout)
	Return the number of channels in the channel layout.
int64_t	av_get_default_channel_layout (int nb_channels)
	Return default channel layout for a given number of channels.
int	av_get_channel_layout_channel_index (uint64_t channel_layout, uint64_t channel)
	Get the index of a channel in channel_layout.
uint64_t	av_channel_layout_extract_channel (uint64_t channel_layout, int index)
	Get the channel with the given index in channel_layout.
const char *	av_get_channel_name (uint64_t channel)
	Get the name of a given channel.
const char *	av_get_channel_description (uint64_t channel)
	Get the description of a given channel.
int	av_get_standard_channel_layout (unsigned index, uint64_t layout, const char *name)
	Get the value and name of a standard channel layout.

Typedef Documentation

typedef struct AVAudioFifo AVAudioFifo

Context for an Audio FIFO Buffer.

Operates at the sample level rather than the byte level.
Supports multiple channels with either planar or packed sample format.
Automatic reallocation when writing to a full buffer.

Definition at line 46 of file audio_fifo.h.

Function Documentation

AVAudioFifo* av_audio_fifo_alloc	(	enum AVSampleFormat	sample_fmt,
		int	channels,
		int	nb_samples
	)

Allocate an AVAudioFifo.

Parameters:

	sample_fmt	sample format
	channels	number of channels
	nb_samples	initial allocation size, in samples

Returns:: newly allocated AVAudioFifo, or NULL on error

Definition at line 60 of file audio_fifo.c.

Referenced by avresample_open(), config_output(), config_props_output(), and ff_buffersink_read_samples_compat().

int av_audio_fifo_drain	(	AVAudioFifo *	af,
		int	nb_samples
	)

Drain data from an AVAudioFifo.

Removes the data without reading it.

Parameters:

	af	AVAudioFifo to drain
	nb_samples	number of samples to drain

Returns:: 0 if OK, or negative AVERROR code on failure

Definition at line 159 of file audio_fifo.c.

Referenced by avresample_read().

void av_audio_fifo_free ( AVAudioFifo * af )

Free an AVAudioFifo.

Parameters:

af

AVAudioFifo to free

Definition at line 45 of file audio_fifo.c.

Referenced by av_audio_fifo_alloc(), avresample_close(), and uninit().

int av_audio_fifo_read	(	AVAudioFifo *	af,
		void **	data,
		int	nb_samples
	)

Read data from an AVAudioFifo.

See also:: enum AVSampleFormat The documentation for AVSampleFormat describes the data layout.

Parameters:

	af	AVAudioFifo to read from
	data	audio data plane pointers
	nb_samples	number of samples to read

Returns:: number of samples actually read, or negative AVERROR code on failure.

Definition at line 139 of file audio_fifo.c.

Referenced by avresample_read(), ff_audio_data_read_from_fifo(), output_frame(), push_samples(), and read_from_fifo().

int av_audio_fifo_realloc	(	AVAudioFifo *	af,
		int	nb_samples
	)

Reallocate an AVAudioFifo.

Parameters:

	af	AVAudioFifo to reallocate
	nb_samples	new allocation size, in samples

Returns:: 0 if OK, or negative AVERROR code on failure

Definition at line 97 of file audio_fifo.c.

Referenced by av_audio_fifo_write(), and filter_samples().

void av_audio_fifo_reset ( AVAudioFifo * af )

Reset the AVAudioFifo buffer.

This empties all data in the buffer.

Parameters:

af

AVAudioFifo to reset

Definition at line 176 of file audio_fifo.c.

int av_audio_fifo_size ( AVAudioFifo * af )

Get the current number of samples in the AVAudioFifo available for reading.

Parameters:

af

the AVAudioFifo to query

Returns:: number of samples available for reading

Definition at line 186 of file audio_fifo.c.

Referenced by av_audio_fifo_write(), avresample_available(), avresample_set_compensation(), ff_buffersink_read_samples_compat(), filter_samples(), get_available_samples(), handle_buffered_output(), push_samples(), and request_samples().

int av_audio_fifo_space ( AVAudioFifo * af )

Get the current number of samples in the AVAudioFifo available for writing.

Parameters:

af

the AVAudioFifo to query

Returns:: number of samples available for writing

Definition at line 191 of file audio_fifo.c.

Referenced by av_audio_fifo_write(), and filter_samples().

int av_audio_fifo_write	(	AVAudioFifo *	af,
		void **	data,
		int	nb_samples
	)

Write data to an AVAudioFifo.

The AVAudioFifo will be reallocated automatically if the available space is less than nb_samples.

See also:: enum AVSampleFormat The documentation for AVSampleFormat describes the data layout.

Parameters:

	af	AVAudioFifo to write to
	data	audio data plane pointers
	nb_samples	number of samples to write

Returns:: number of samples actually written, or negative AVERROR code on failure.

Definition at line 113 of file audio_fifo.c.

Referenced by ff_audio_data_add_to_fifo(), ff_buffersink_read_samples_compat(), and filter_samples().

void av_bprint_channel_layout	(	struct AVBPrint *	bp,
		int	nb_channels,
		uint64_t	channel_layout
	)

Append a description of a channel layout to a bprint buffer.

Definition at line 147 of file audioconvert.c.

Referenced by av_get_channel_layout_string(), config_output(), and show_frame().

uint64_t av_channel_layout_extract_channel	(	uint64_t	channel_layout,
		int	index
	)

Get the channel with the given index in channel_layout.

Definition at line 235 of file audioconvert.c.

Referenced by filter_samples(), guess_map_any(), init(), join_config_output(), join_init(), and query_formats().

const char* av_get_channel_description ( uint64_t channel )

Get the description of a given channel.

Parameters:

channel

a channel layout with a single channel

Returns:: channel description on success, NULL on error

Definition at line 224 of file audioconvert.c.

Referenced by show_layouts().

uint64_t av_get_channel_layout ( const char * name )

Return a channel layout id that matches name, or 0 if no match is found.

name can be one or several of the following notations, separated by '+' or '|':

the name of an usual channel layout (mono, stereo, 4.0, quad, 5.0, 5.0(side), 5.1, 5.1(side), 7.1, 7.1(wide), downmix);
the name of a single channel (FL, FR, FC, LFE, BL, BR, FLC, FRC, BC, SL, SR, TC, TFL, TFC, TFR, TBL, TBC, TBR, DL, DR);
a number of channels, in decimal, optionally followed by 'c', yielding the default channel layout for that number of channels (
See also:
av_get_default_channel_layout);
a channel layout mask, in hexadecimal starting with "0x" (see the AV_CH_* macros).

Example: "stereo+FC" = "2+FC" = "2c+1c" = "0x7"

Definition at line 131 of file audioconvert.c.

Referenced by channelmap_init(), ff_parse_channel_layout(), get_channel(), init(), init_audio(), join_init(), opt_channel_layout(), and parse_channel_name().

int av_get_channel_layout_channel_index	(	uint64_t	channel_layout,
		uint64_t	channel
	)

Get the index of a channel in channel_layout.

Parameters:

channel

a channel layout describing exactly one channel which must be present in channel_layout.

Returns:: index of channel in channel_layout on success, a negative AVERROR on error.

Definition at line 203 of file audioconvert.c.

Referenced by channelmap_config_input(), channelmap_init(), join_config_output(), and parse_maps().

int av_get_channel_layout_nb_channels ( uint64_t channel_layout )

Return the number of channels in the channel layout.

Definition at line 190 of file audioconvert.c.

Referenced by audio_decode_frame(), audio_encode_example(), audio_open(), auto_matrix(), av_asrc_buffer_add_buffer(), av_bprint_channel_layout(), av_buffersink_read_samples(), av_channel_layout_extract_channel(), av_get_channel_description(), av_get_channel_layout_channel_index(), av_get_channel_name(), avcodec_open2(), avfilter_copy_buf_props(), avfilter_get_audio_buffer_ref_from_arrays(), avfilter_ref_buffer(), avresample_build_matrix(), avresample_get_matrix(), avresample_open(), avresample_set_matrix(), buffer_offset(), calc_ptr_alignment(), channelmap_filter_samples(), channelmap_init(), config_output(), config_props(), config_props_output(), ff_buffersink_read_samples_compat(), ff_copy_buffer_ref(), ff_default_get_audio_buffer(), ff_filter_samples(), ff_filter_samples_framed(), ff_mov_get_channel_layout_tag(), filter_samples(), get_channel(), init(), join_init(), lavfi_read_header(), lavfi_read_packet(), main(), mov_read_dec3(), opt_channel_layout(), plot_spectrum_column(), print_samplesref(), push_samples(), query_formats(), read_major_sync(), return_audio_frame(), sane_layout(), select_channel_layout(), send_silence(), swap_channel_layouts_on_filter(), swr_alloc_set_opts(), swr_init(), swr_set_matrix(), swri_rematrix(), swri_rematrix_init(), swri_rematrix_init_x86(), and transcode_init().

void av_get_channel_layout_string	(	char *	buf,
		int	buf_size,
		int	nb_channels,
		uint64_t	channel_layout
	)

Return a description of a channel layout.

If nb_channels is <= 0, it is guessed from the channel_layout.

Parameters:

	buf	put here the string containing the channel layout
	buf_size	size in bytes of the buffer

Definition at line 181 of file audioconvert.c.

Referenced by auto_matrix(), avcodec_string(), channelmap_config_input(), channelmap_init(), clean_layout(), config_output(), config_props(), decode_audio(), dprint_options(), ff_alsa_open(), ff_audio_mix_init(), ff_tlog_link(), filter_samples(), guess_channel_layout(), guess_input_channel_layout(), init_filters(), main(), oggvorbis_init_encoder(), print_digraph(), print_link_prop(), and query_formats().

const char* av_get_channel_name ( uint64_t channel )

Get the name of a given channel.

Returns:: channel name on success, NULL on error.

Definition at line 213 of file audioconvert.c.

Referenced by channelmap_config_input(), init(), join_config_output(), and show_layouts().

int64_t av_get_default_channel_layout ( int nb_channels )

Return default channel layout for a given number of channels.

Definition at line 195 of file audioconvert.c.

Referenced by audio_decode_frame(), audio_open(), channelmap_init(), configure_output_audio_filter(), encode_init(), get_channel_layout_single(), guess_channel_layout(), guess_input_channel_layout(), init(), init_filters(), query_formats(), set_channel_info(), and swr_init().

int av_get_standard_channel_layout	(	unsigned	index,
		uint64_t *	layout,
		const char **	name
	)

Get the value and name of a standard channel layout.

Parameters:

`[in]`	index	index in an internal list, starting at 0
`[out]`	layout	channel layout mask
`[out]`	name	name of the layout

Returns:: 0 if the layout exists, <0 if index is beyond the limits

Definition at line 249 of file audioconvert.c.

Referenced by show_layouts().

Audio related [Common utility functions]

Modules

Typedefs

Functions

Typedef Documentation

Function Documentation

Audio related
[Common utility functions]