libavutil/samplefmt.h File Reference

#include <stdint.h>
#include "avutil.h"
#include "attributes.h"

Go to the source code of this file.

Enumerations

enum AVSampleFormat {
  AV_SAMPLE_FMT_NONE = -1, AV_SAMPLE_FMT_U8, AV_SAMPLE_FMT_S16, AV_SAMPLE_FMT_S32,
  AV_SAMPLE_FMT_FLT, AV_SAMPLE_FMT_DBL, AV_SAMPLE_FMT_U8P, AV_SAMPLE_FMT_S16P,
  AV_SAMPLE_FMT_S32P, AV_SAMPLE_FMT_FLTP, AV_SAMPLE_FMT_DBLP, AV_SAMPLE_FMT_NB
}

Audio Sample Formats. More...

Functions

const char * av_get_sample_fmt_name (enum AVSampleFormat sample_fmt)

Return the name of sample_fmt, or NULL if sample_fmt is not recognized.

enum AVSampleFormat av_get_sample_fmt (const char *name)

Return a sample format corresponding to name, or AV_SAMPLE_FMT_NONE on error.

enum AVSampleFormat av_get_alt_sample_fmt (enum AVSampleFormat sample_fmt, int planar)

Return the planar<->packed alternative form of the given sample format, or AV_SAMPLE_FMT_NONE on error.

enum AVSampleFormat av_get_packed_sample_fmt (enum AVSampleFormat sample_fmt)

Get the packed alternative form of the given sample format.

enum AVSampleFormat av_get_planar_sample_fmt (enum AVSampleFormat sample_fmt)

Get the planar alternative form of the given sample format.

char * av_get_sample_fmt_string (char *buf, int buf_size, enum AVSampleFormat sample_fmt)

Generate a string corresponding to the sample format with sample_fmt, or a header if sample_fmt is negative.

attribute_deprecated int av_get_bits_per_sample_fmt (enum AVSampleFormat sample_fmt)

int av_get_bytes_per_sample (enum AVSampleFormat sample_fmt)

Return number of bytes per sample.

int av_sample_fmt_is_planar (enum AVSampleFormat sample_fmt)

Check if the sample format is planar.

int av_samples_get_buffer_size (int *linesize, int nb_channels, int nb_samples, enum AVSampleFormat sample_fmt, int align)

Get the required buffer size for the given audio parameters.

int av_samples_fill_arrays (uint8_t **audio_data, int *linesize, const uint8_t *buf, int nb_channels, int nb_samples, enum AVSampleFormat sample_fmt, int align)

Fill plane data pointers and linesize for samples with sample format sample_fmt.

int av_samples_alloc (uint8_t **audio_data, int *linesize, int nb_channels, int nb_samples, enum AVSampleFormat sample_fmt, int align)

Allocate a samples buffer for nb_samples samples, and fill data pointers and linesize accordingly.

int av_samples_copy (uint8_t **dst, uint8_t *const *src, int dst_offset, int src_offset, int nb_samples, int nb_channels, enum AVSampleFormat sample_fmt)

Copy samples from src to dst.

int av_samples_set_silence (uint8_t **audio_data, int offset, int nb_samples, int nb_channels, enum AVSampleFormat sample_fmt)

Fill an audio buffer with silence.

Enumeration Type Documentation

enum AVSampleFormat

Audio Sample Formats.

: The data described by the sample format is always in native-endian order. Sample values can be expressed by native C types, hence the lack of a signed 24-bit sample format even though it is a common raw audio data format.

: The floating-point formats are based on full volume being in the range [-1.0, 1.0]. Any values outside this range are beyond full volume level.

: The data layout as used in av_samples_fill_arrays() and elsewhere in Libav (such as AVFrame in libavcodec) is as follows:

For planar sample formats, each audio channel is in a separate data plane, and linesize is the buffer size, in bytes, for a single plane. All data planes must be the same size. For packed sample formats, only the first data plane is used, and samples for each channel are interleaved. In this case, linesize is the buffer size, in bytes, for the 1 plane.

Enumerator:

AV_SAMPLE_FMT_NONE
AV_SAMPLE_FMT_U8	unsigned 8 bits
AV_SAMPLE_FMT_S16	signed 16 bits
AV_SAMPLE_FMT_S32	signed 32 bits
AV_SAMPLE_FMT_FLT	float
AV_SAMPLE_FMT_DBL	double
AV_SAMPLE_FMT_U8P	unsigned 8 bits, planar
AV_SAMPLE_FMT_S16P	signed 16 bits, planar
AV_SAMPLE_FMT_S32P	signed 32 bits, planar
AV_SAMPLE_FMT_FLTP	float, planar
AV_SAMPLE_FMT_DBLP	double, planar
AV_SAMPLE_FMT_NB	Number of sample formats. DO NOT USE if linking dynamically.

Definition at line 49 of file samplefmt.h.

Function Documentation

enum AVSampleFormat av_get_alt_sample_fmt	(	enum AVSampleFormat	sample_fmt,
		int	planar
	)

Return the planar<->packed alternative form of the given sample format, or AV_SAMPLE_FMT_NONE on error.

If the passed sample_fmt is already in the requested planar/packed format, the format returned is the same as the input.

Definition at line 64 of file samplefmt.c.

Referenced by get(), set(), and shift().

attribute_deprecated int av_get_bits_per_sample_fmt ( enum AVSampleFormat sample_fmt )

Deprecated:: Use av_get_bytes_per_sample() instead.

Definition at line 111 of file samplefmt.c.

int av_get_bytes_per_sample ( enum AVSampleFormat sample_fmt )

Return number of bytes per sample.

Parameters:

sample_fmt

the sample format

Returns:: number of bytes per sample or zero if unknown for the given sample format

Definition at line 104 of file samplefmt.c.

Referenced by audio_decode_frame(), audio_resample(), av_asrc_buffer_add_buffer(), av_audio_resample_init(), av_samples_copy(), av_samples_get_buffer_size(), av_samples_set_silence(), avresample_open(), buffer_offset(), config_output(), decode_frame(), decode_init(), ff_audio_data_alloc(), ff_audio_data_init(), ff_audio_resample_init(), filter_samples(), flac_set_bps(), lavfi_read_packet(), mkv_write_tracks(), mp3lame_encode_init(), open_audio(), sdl_audio_callback(), set_audiodata_fmt(), setup_array(), shift(), swap_sample_fmts_on_filter(), swri_rematrix(), swri_resample_init(), vmdaudio_decode_init(), wavpack_decode_block(), write_audio_frame(), and yae_reset().

enum AVSampleFormat av_get_packed_sample_fmt ( enum AVSampleFormat sample_fmt )

Get the packed alternative form of the given sample format.

If the passed sample_fmt is already in packed format, the format returned is the same as the input.

Returns:: the packed alternative form of the given sample format or AV_SAMPLE_FMT_NONE on error.

Definition at line 73 of file samplefmt.c.

Referenced by auto_matrix(), ff_audio_convert_set_func(), PUT_FUNC(), swap_sample_fmts_on_filter(), and swri_get_dither().

enum AVSampleFormat av_get_planar_sample_fmt ( enum AVSampleFormat sample_fmt )

Get the planar alternative form of the given sample format.

If the passed sample_fmt is already in planar format, the format returned is the same as the input.

Returns:: the planar alternative form of the given sample format or AV_SAMPLE_FMT_NONE on error.

Definition at line 82 of file samplefmt.c.

Referenced by avresample_open(), swap_sample_fmts_on_filter(), and swr_init().

enum AVSampleFormat av_get_sample_fmt ( const char * name )

Return a sample format corresponding to name, or AV_SAMPLE_FMT_NONE on error.

Definition at line 54 of file samplefmt.c.

Referenced by ff_parse_sample_format(), init(), init_audio(), and new_audio_stream().

const char* av_get_sample_fmt_name ( enum AVSampleFormat sample_fmt )

Return the name of sample_fmt, or NULL if sample_fmt is not recognized.

Definition at line 47 of file samplefmt.c.

Referenced by audio_decode_frame(), audio_encode_example(), av_audio_resample_init(), avcodec_string(), avresample_open(), choose_sample_fmt(), config_output(), config_props(), configure_input_audio_filter(), decode_audio(), dprint_options(), ff_audio_convert_set_func(), ff_audio_mix_init(), ff_audio_mix_set_func(), ff_audio_resample_init(), ff_tlog_link(), filter_samples(), get_format_from_sample_fmt(), init_filters(), lavfi_read_header(), main(), mix_function_init(), print_digraph(), print_link_prop(), show_frame(), show_stream(), and swr_init().

char* av_get_sample_fmt_string	(	char *	buf,
		int	buf_size,
		enum AVSampleFormat	sample_fmt
	)

Generate a string corresponding to the sample format with sample_fmt, or a header if sample_fmt is negative.

Parameters:

	buf	the buffer where to write the string
	buf_size	the size of buf
	sample_fmt	the number of the sample format to print the corresponding info string, or a negative value to print the corresponding header.

Returns:: the pointer to the filled buffer or NULL if sample_fmt is unknown or in case of other errors

Definition at line 91 of file samplefmt.c.

Referenced by show_sample_fmts().

int av_sample_fmt_is_planar ( enum AVSampleFormat sample_fmt )

Check if the sample format is planar.

Parameters:

sample_fmt

the sample format to inspect

Returns:: 1 if the sample format is planar, 0 if it is interleaved

Definition at line 118 of file samplefmt.c.

Referenced by alac_decode_init(), allocate_buffers(), av_audio_fifo_alloc(), av_samples_copy(), av_samples_fill_arrays(), av_samples_get_buffer_size(), av_samples_set_silence(), avcodec_decode_audio3(), avcodec_encode_audio2(), avcodec_fill_audio_frame(), avfilter_copy_buf_props(), avfilter_get_audio_buffer_ref_from_arrays(), buffer_offset(), calc_ptr_alignment(), config_output(), decode_element(), ff_audio_data_alloc(), ff_audio_data_init(), ff_default_get_audio_buffer(), ff_planar_sample_fmts(), filter_samples(), flac_set_bps(), get(), main(), set(), set_audiodata_fmt(), setup_array(), and shift().

int av_samples_alloc	(	uint8_t **	audio_data,
		int *	linesize,
		int	nb_channels,
		int	nb_samples,
		enum AVSampleFormat	sample_fmt,
		int	align
	)

Allocate a samples buffer for nb_samples samples, and fill data pointers and linesize accordingly.

The allocated samples buffer can be freed by using av_freep(&audio_data[0])

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

Parameters:

`[out]`	audio_data	array to be filled with the pointer for each channel
`[out]`	linesize	aligned size for audio buffer(s), may be NULL
	nb_channels	number of audio channels
	nb_samples	number of samples per channel
	align	buffer size alignment (0 = default, 1 = no alignment)

Returns:: 0 on success or a negative error code on failure

See also:: av_samples_fill_arrays()

Definition at line 177 of file samplefmt.c.

Referenced by decode_packet(), ff_audio_data_realloc(), and ff_default_get_audio_buffer().

int av_samples_copy	(	uint8_t **	dst,
		uint8_t const	src,
		int	dst_offset,
		int	src_offset,
		int	nb_samples,
		int	nb_channels,
		enum AVSampleFormat	sample_fmt
	)

Copy samples from src to dst.

Parameters:

	dst	destination array of pointers to data planes
	src	source array of pointers to data planes
	dst_offset	offset in samples at which the data will be written to dst
	src_offset	offset in samples at which the data will be read from src
	nb_samples	number of samples to be copied
	nb_channels	number of audio channels
	sample_fmt	audio sample format

Definition at line 199 of file samplefmt.c.

Referenced by av_buffersink_read_samples(), avcodec_decode_audio4(), decode_packet(), ff_copy_buffer_ref(), ff_filter_samples(), ff_filter_samples_framed(), pad_last_frame(), and return_audio_frame().

int av_samples_fill_arrays	(	uint8_t **	audio_data,
		int *	linesize,
		const uint8_t *	buf,
		int	nb_channels,
		int	nb_samples,
		enum AVSampleFormat	sample_fmt,
		int	align
	)

Fill plane data pointers and linesize for samples with sample format sample_fmt.

The audio_data array is filled with the pointers to the samples data planes: for planar, set the start point of each channel's data within the buffer, for packed, set the start point of the entire buffer only.

The value pointed to by linesize is set to the aligned size of each channel's data buffer for planar layout, or to the aligned size of the buffer for all channels for packed layout.

The buffer in buf must be big enough to contain all the samples (use av_samples_get_buffer_size() to compute its minimum size), otherwise the audio_data pointers will point to invalid data.

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

Parameters:

`[out]`	audio_data	array to be filled with the pointer for each channel
`[out]`	linesize	calculated linesize, may be NULL
	buf	the pointer to a buffer containing the samples
	nb_channels	the number of channels
	nb_samples	the number of samples in a single channel
	sample_fmt	the sample format
	align	buffer size alignment (0 = default, 1 = no alignment)

Returns:: 0 on success or a negative error code on failure

Definition at line 155 of file samplefmt.c.

Referenced by av_asrc_buffer_add_buffer(), av_samples_alloc(), avcodec_fill_audio_frame(), ff_audio_data_realloc(), and main().

int av_samples_get_buffer_size	(	int *	linesize,
		int	nb_channels,
		int	nb_samples,
		enum AVSampleFormat	sample_fmt,
		int	align
	)

Get the required buffer size for the given audio parameters.

Parameters:

`[out]`	linesize	calculated linesize, may be NULL
	nb_channels	the number of channels
	nb_samples	the number of samples in a single channel
	sample_fmt	the sample format
	align	buffer size alignment (0 = default, 1 = no alignment)

Returns:: required buffer size, or negative error code on failure

Definition at line 125 of file samplefmt.c.

Referenced by audio_decode_example(), audio_decode_frame(), audio_encode_example(), audio_get_buffer(), av_audio_fifo_alloc(), av_audio_fifo_realloc(), av_samples_alloc(), av_samples_fill_arrays(), avcodec_decode_audio3(), avcodec_encode_audio(), avcodec_fill_audio_frame(), decode_packet(), ff_audio_data_realloc(), main(), pad_last_frame(), sdl_audio_callback(), and stream_component_open().

int av_samples_set_silence	(	uint8_t **	audio_data,
		int	offset,
		int	nb_samples,
		int	nb_channels,
		enum AVSampleFormat	sample_fmt
	)

Fill an audio buffer with silence.

Parameters:

	audio_data	array of pointers to data planes
	offset	offset in samples at which to start filling
	nb_samples	number of samples to fill
	nb_channels	number of audio channels
	sample_fmt	audio sample format

Definition at line 223 of file samplefmt.c.

Referenced by filter_samples(), pad_last_frame(), push_samples(), return_audio_frame(), and send_silence().


Enumerations
enum	AVSampleFormat { AV_SAMPLE_FMT_NONE = -1, AV_SAMPLE_FMT_U8, AV_SAMPLE_FMT_S16, AV_SAMPLE_FMT_S32, AV_SAMPLE_FMT_FLT, AV_SAMPLE_FMT_DBL, AV_SAMPLE_FMT_U8P, AV_SAMPLE_FMT_S16P, AV_SAMPLE_FMT_S32P, AV_SAMPLE_FMT_FLTP, AV_SAMPLE_FMT_DBLP, AV_SAMPLE_FMT_NB }
	Audio Sample Formats. More...
Functions
const char *	av_get_sample_fmt_name (enum AVSampleFormat sample_fmt)
	Return the name of sample_fmt, or NULL if sample_fmt is not recognized.
enum AVSampleFormat	av_get_sample_fmt (const char *name)
	Return a sample format corresponding to name, or AV_SAMPLE_FMT_NONE on error.
enum AVSampleFormat	av_get_alt_sample_fmt (enum AVSampleFormat sample_fmt, int planar)
	Return the planar<->packed alternative form of the given sample format, or AV_SAMPLE_FMT_NONE on error.
enum AVSampleFormat	av_get_packed_sample_fmt (enum AVSampleFormat sample_fmt)
	Get the packed alternative form of the given sample format.
enum AVSampleFormat	av_get_planar_sample_fmt (enum AVSampleFormat sample_fmt)
	Get the planar alternative form of the given sample format.
char *	av_get_sample_fmt_string (char *buf, int buf_size, enum AVSampleFormat sample_fmt)
	Generate a string corresponding to the sample format with sample_fmt, or a header if sample_fmt is negative.
attribute_deprecated int	av_get_bits_per_sample_fmt (enum AVSampleFormat sample_fmt)
int	av_get_bytes_per_sample (enum AVSampleFormat sample_fmt)
	Return number of bytes per sample.
int	av_sample_fmt_is_planar (enum AVSampleFormat sample_fmt)
	Check if the sample format is planar.
int	av_samples_get_buffer_size (int *linesize, int nb_channels, int nb_samples, enum AVSampleFormat sample_fmt, int align)
	Get the required buffer size for the given audio parameters.
int	av_samples_fill_arrays (uint8_t *audio_data, int linesize, const uint8_t *buf, int nb_channels, int nb_samples, enum AVSampleFormat sample_fmt, int align)
	Fill plane data pointers and linesize for samples with sample format sample_fmt.
int	av_samples_alloc (uint8_t *audio_data, int linesize, int nb_channels, int nb_samples, enum AVSampleFormat sample_fmt, int align)
	Allocate a samples buffer for nb_samples samples, and fill data pointers and linesize accordingly.
int	av_samples_copy (uint8_t *dst, uint8_t const *src, int dst_offset, int src_offset, int nb_samples, int nb_channels, enum AVSampleFormat sample_fmt)
	Copy samples from src to dst.
int	av_samples_set_silence (uint8_t **audio_data, int offset, int nb_samples, int nb_channels, enum AVSampleFormat sample_fmt)
	Fill an audio buffer with silence.