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#ifndef foosamplehfoo
#define foosamplehfoo
/* $Id$ */
/***
This file is part of polypaudio.
polypaudio is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published
by the Free Software Foundation; either version 2 of the License,
or (at your option) any later version.
polypaudio is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public License
along with polypaudio; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
USA.
***/
#include <inttypes.h>
#include <sys/types.h>
#include "cdecl.h"
/** \file
* Constants and routines for sample type handling */
PA_C_DECL_BEGIN
/** Sample format */
enum pa_sample_format {
PA_SAMPLE_U8, /**< Unsigned 8 Bit PCM */
PA_SAMPLE_ALAW, /**< 8 Bit a-Law */
PA_SAMPLE_ULAW, /**< 8 Bit mu-Law */
PA_SAMPLE_S16LE, /**< Signed 16 Bit PCM, little endian (PC) */
PA_SAMPLE_S16BE, /**< Signed 16 Bit PCM, big endian */
PA_SAMPLE_FLOAT32LE, /**< 32 Bit IEEE floating point, little endian, range -1..1 */
PA_SAMPLE_FLOAT32BE, /**< 32 Bit IEEE floating point, big endian, range -1..1 */
PA_SAMPLE_MAX /**< Upper limit of valid sample types */
};
#ifdef WORDS_BIGENDIAN
/** Signed 16 Bit PCM, native endian */
#define PA_SAMPLE_S16NE PA_SAMPLE_S16BE
/** 32 Bit IEEE floating point, native endian */
#define PA_SAMPLE_FLOAT32NE PA_SAMPLE_FLOAT32BE
#else
/** Signed 16 Bit PCM, native endian */
#define PA_SAMPLE_S16NE PA_SAMPLE_S16LE
/** 32 Bit IEEE floating point, native endian */
#define PA_SAMPLE_FLOAT32NE PA_SAMPLE_FLOAT32LE
#endif
/** A Shortcut for PA_SAMPLE_FLOAT32NE */
#define PA_SAMPLE_FLOAT32 PA_SAMPLE_FLOAT32NE
/** A sample format and attribute specification */
struct pa_sample_spec {
enum pa_sample_format format; /**< The sample format */
uint32_t rate; /**< The sample rate. (e.g. 44100) */
uint8_t channels; /**< Audio channels. (1 for mono, 2 for stereo, ...) */
};
/** Type for usec specifications */
typedef uint32_t pa_usec_t;
/** Return the amount of bytes playback of a second of audio with the speicified sample type takes */
size_t pa_bytes_per_second(const struct pa_sample_spec *spec);
/** Return the size of a frame with the specific sample type */
size_t pa_frame_size(const struct pa_sample_spec *spec);
/** Calculate the time the specified bytes take to play with the specified sample type */
pa_usec_t pa_bytes_to_usec(size_t length, const struct pa_sample_spec *spec);
/** Return non-zero when the sample type specification is valid */
int pa_sample_spec_valid(const struct pa_sample_spec *spec);
/** Return non-zero when the two sample type specifications match */
int pa_sample_spec_equal(const struct pa_sample_spec*a, const struct pa_sample_spec*b);
/** Maximum required string length for pa_sample_spec_snprint() */
#define PA_SAMPLE_SNPRINT_MAX_LENGTH 32
/** Pretty print a sample type specification to a string */
void pa_sample_spec_snprint(char *s, size_t l, const struct pa_sample_spec *spec);
/** Volume specification: 0: silence; < 256: diminished volume; 256: normal volume; > 256 amplified volume */
typedef uint32_t pa_volume_t;
/** Normal volume (100%) */
#define PA_VOLUME_NORM (0x100)
/** Muted volume (0%) */
#define PA_VOLUME_MUTED (0)
/** Multiply two volumes specifications, return the result. This uses PA_VOLUME_NORM as neutral element of multiplication. */
pa_volume_t pa_volume_multiply(pa_volume_t a, pa_volume_t b);
/** Convert volume from decibel to linear level */
pa_volume_t pa_volume_from_dB(double f);
/** Convert volume from linear level to decibel */
double pa_volume_to_dB(pa_volume_t v);
PA_C_DECL_END
#endif
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