pcm_volume.h File Reference

#include "pcm_prng.h"
#include <stdint.h>
#include <stdbool.h>

Go to the source code of this file.

Enumerations
enum	{ PCM_VOLUME_1 = 1024 }

Functions
static int	pcm_float_to_volume (float volume)
	Converts a float value (0.0 = silence, 1.0 = 100% volume) to an integer volume value (1000 = 100%).
static int	pcm_volume_dither (void)
	Returns the next volume dithering number, between -511 and +511.
bool	pcm_volume (void *buffer, int length, const struct audio_format *format, int volume)
	Adjust the volume of the specified PCM buffer.

Enumeration Type Documentation

anonymous enum

Enumerator:

PCM_VOLUME_1

this value means "100% volume"

Definition at line 28 of file pcm_volume.h.

Function Documentation

static int pcm_float_to_volume ( float  volume )

inlinestatic

Converts a float value (0.0 = silence, 1.0 = 100% volume) to an integer volume value (1000 = 100%).

Definition at line 40 of file pcm_volume.h.

bool pcm_volume	(	void *	buffer,
		int	length,
		const struct audio_format *	format,
		int	volume
	)

Adjust the volume of the specified PCM buffer.

Parameters

buffer	the PCM buffer
length	the length of the PCM buffer
format	the audio format of the PCM buffer
volume	the volume between 0 and PCM_VOLUME_1

Returns

true on success, false if the audio format is not supported

static int pcm_volume_dither ( void  )

inlinestatic

Returns the next volume dithering number, between -511 and +511.

This number is taken from a global PRNG, see pcm_prng().

Definition at line 50 of file pcm_volume.h.