libavutil/samplefmt.c File Reference

#include "samplefmt.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

Go to the source code of this file.

Data Structures
struct	SampleFmtInfo
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.
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.
int	av_get_bits_per_sample_fmt (enum AVSampleFormat sample_fmt)
	Return sample format bits per sample.
int	av_samples_fill_arrays (uint8_t *pointers[8], int linesizes[8], uint8_t *buf, int nb_channels, int nb_samples, enum AVSampleFormat sample_fmt, int planar, int align)
	Fill channel data pointers and linesizes for samples with sample format sample_fmt.
int	av_samples_alloc (uint8_t *pointers[8], int linesizes[8], int nb_samples, int nb_channels, enum AVSampleFormat sample_fmt, int planar, int align)
	Allocate a samples buffer for nb_samples samples, and fill pointers and linesizes accordingly.
Variables
static const SampleFmtInfo	sample_fmt_info [AV_SAMPLE_FMT_NB]
	this table gives more information about formats

---

Function Documentation

int av_get_bits_per_sample_fmt

(

enum AVSampleFormat

sample_fmt

)

Return sample format bits per sample.

Parameters:

sample_fmt

the sample format

Returns:

number of bits per sample or zero if unknown for the given sample format

Definition at line 69 of file samplefmt.c.

Referenced by audio_decode_frame(), av_audio_resample_init(), av_get_bits_per_sample_format(), av_samples_fill_arrays(), avfilter_default_get_audio_buffer(), decode_frame(), decode_init(), do_audio_out(), mkv_write_tracks(), output_packet(), and vmdaudio_decode_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 46 of file samplefmt.c.

Referenced by avcodec_get_sample_fmt(), and opt_audio_sample_fmt().

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 39 of file samplefmt.c.

Referenced by audio_decode_frame(), av_audio_resample_init(), avcodec_get_sample_fmt_name(), avcodec_string(), choose_sample_fmt(), do_audio_out(), ff_dlog_link(), and print_digraph().

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 56 of file samplefmt.c.

Referenced by avcodec_sample_fmt_string(), and opt_audio_sample_fmt().

int av_samples_alloc	(	uint8_t *	pointers[8],
		int	linesizes[8],
		int	nb_samples,
		int	nb_channels,
		enum AVSampleFormat	sample_fmt,
		int	planar,
		int	align
	)

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

The allocated samples buffer has to be freed by using av_freep(&pointers[0]).

Parameters:

	nb_samples	number of samples per channel
	planar	1 if the samples layout is planar, 0 if packed,
	align	the value to use for buffer size alignment

Returns:

the size in bytes required for the samples buffer, a negative error code in case of failure

See also:

av_samples_fill_arrays()

Definition at line 103 of file samplefmt.c.

int av_samples_fill_arrays	(	uint8_t *	pointers[8],
		int	linesizes[8],
		uint8_t *	buf,
		int	nb_channels,
		int	nb_samples,
		enum AVSampleFormat	sample_fmt,
		int	planar,
		int	align
	)

Fill channel data pointers and linesizes for samples with sample format sample_fmt.

The pointers array is filled with the pointers to the samples data: data[c] points to the first sample of channel c. data[c] + linesize[0] points to the second sample of channel c

Parameters:

	pointers	array to be filled with the pointer for each plane, may be NULL
	linesizes	array to be filled with the linesize, may be NULL
	buf	the pointer to a buffer containing the samples
	nb_samples	the number of samples in a single channel
	planar	1 if the samples layout is planar, 0 if it is packed
	nb_channels	the number of channels

Returns:

the total size of the buffer, a negative error code in case of failure

Definition at line 75 of file samplefmt.c.

Referenced by av_samples_alloc().

---

Variable Documentation

const SampleFmtInfo sample_fmt_info[AV_SAMPLE_FMT_NB] [static]

Initial value:

 {
    [AV_SAMPLE_FMT_U8]  = { .name = "u8",  .bits = 8 },
    [AV_SAMPLE_FMT_S16] = { .name = "s16", .bits = 16 },
    [AV_SAMPLE_FMT_S32] = { .name = "s32", .bits = 32 },
    [AV_SAMPLE_FMT_FLT] = { .name = "flt", .bits = 32 },
    [AV_SAMPLE_FMT_DBL] = { .name = "dbl", .bits = 64 },
}

this table gives more information about formats

Definition at line 31 of file samplefmt.c.