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|
#ifndef foosamplehfoo
#define foosamplehfoo
/***
This file is part of PulseAudio.
Copyright 2004-2006 Lennart Poettering
Copyright 2006 Pierre Ossman <ossman@cendio.se> for Cendio AB
PulseAudio is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published
by the Free Software Foundation; either version 2.1 of the License,
or (at your option) any later version.
PulseAudio 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 Lesser General Public License
along with PulseAudio; if not, see <http://www.gnu.org/licenses/>.
***/
#include <inttypes.h>
#include <sys/types.h>
#include <sys/param.h>
#include <pulse/gccmacro.h>
#include <pulse/cdecl.h>
#include <pulse/version.h>
/** \page sample Sample Format Specifications
*
* \section overv_sec Overview
*
* PulseAudio is capable of handling a multitude of sample formats, rates
* and channels, transparently converting and mixing them as needed.
*
* \section format_sec Sample Format
*
* PulseAudio supports the following sample formats:
*
* \li PA_SAMPLE_U8 - Unsigned 8 bit integer PCM.
* \li PA_SAMPLE_S16LE - Signed 16 integer bit PCM, little endian.
* \li PA_SAMPLE_S16BE - Signed 16 integer bit PCM, big endian.
* \li PA_SAMPLE_FLOAT32LE - 32 bit IEEE floating point PCM, little endian.
* \li PA_SAMPLE_FLOAT32BE - 32 bit IEEE floating point PCM, big endian.
* \li PA_SAMPLE_ALAW - 8 bit a-Law.
* \li PA_SAMPLE_ULAW - 8 bit mu-Law.
* \li PA_SAMPLE_S32LE - Signed 32 bit integer PCM, little endian.
* \li PA_SAMPLE_S32BE - Signed 32 bit integer PCM, big endian.
* \li PA_SAMPLE_S24LE - Signed 24 bit integer PCM packed, little endian.
* \li PA_SAMPLE_S24BE - Signed 24 bit integer PCM packed, big endian.
* \li PA_SAMPLE_S24_32LE - Signed 24 bit integer PCM in LSB of 32 bit words, little endian.
* \li PA_SAMPLE_S24_32BE - Signed 24 bit integer PCM in LSB of 32 bit words, big endian.
*
* The floating point sample formats have the range from -1.0 to 1.0.
*
* The sample formats that are sensitive to endianness have convenience
* macros for native endian (NE), and reverse endian (RE).
*
* \section rate_sec Sample Rates
*
* PulseAudio supports any sample rate between 1 Hz and 192000 Hz. There is no
* point trying to exceed the sample rate of the output device though as the
* signal will only get downsampled, consuming CPU on the machine running the
* server.
*
* \section chan_sec Channels
*
* PulseAudio supports up to 32 individual channels. The order of the
* channels is up to the application, but they must be continuous. To map
* channels to speakers, see \ref channelmap.
*
* \section calc_sec Calculations
*
* The PulseAudio library contains a number of convenience functions to do
* calculations on sample formats:
*
* \li pa_bytes_per_second() - The number of bytes one second of audio will
* take given a sample format.
* \li pa_frame_size() - The size, in bytes, of one frame (i.e. one set of
* samples, one for each channel).
* \li pa_sample_size() - The size, in bytes, of one sample.
* \li pa_bytes_to_usec() - Calculate the time it would take to play a buffer
* of a certain size.
*
* \section util_sec Convenience Functions
*
* The library also contains a couple of other convenience functions:
*
* \li pa_sample_spec_valid() - Tests if a sample format specification is
* valid.
* \li pa_sample_spec_equal() - Tests if the sample format specifications are
* identical.
* \li pa_sample_format_to_string() - Return a textual description of a
* sample format.
* \li pa_parse_sample_format() - Parse a text string into a sample format.
* \li pa_sample_spec_snprint() - Create a textual description of a complete
* sample format specification.
* \li pa_bytes_snprint() - Pretty print a byte value (e.g. 2.5 MiB).
*/
/** \file
* Constants and routines for sample type handling
*
* See also \subpage sample
*/
PA_C_DECL_BEGIN
#if !defined(WORDS_BIGENDIAN)
#if defined(__BYTE_ORDER)
#if __BYTE_ORDER == __BIG_ENDIAN
#define WORDS_BIGENDIAN
#endif
#endif
/* On Sparc, WORDS_BIGENDIAN needs to be set if _BIG_ENDIAN is defined. */
#if defined(__sparc__) && defined(_BIG_ENDIAN)
#define WORDS_BIGENDIAN
#endif
#endif
/** Maximum number of allowed channels */
#define PA_CHANNELS_MAX 32U
/** Maximum allowed sample rate */
#define PA_RATE_MAX (48000U*8U)
/** Sample format */
typedef 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 (PC), range -1.0 to 1.0 */
PA_SAMPLE_FLOAT32BE,
/**< 32 Bit IEEE floating point, big endian, range -1.0 to 1.0 */
PA_SAMPLE_S32LE,
/**< Signed 32 Bit PCM, little endian (PC) */
PA_SAMPLE_S32BE,
/**< Signed 32 Bit PCM, big endian */
PA_SAMPLE_S24LE,
/**< Signed 24 Bit PCM packed, little endian (PC). \since 0.9.15 */
PA_SAMPLE_S24BE,
/**< Signed 24 Bit PCM packed, big endian. \since 0.9.15 */
PA_SAMPLE_S24_32LE,
/**< Signed 24 Bit PCM in LSB of 32 Bit words, little endian (PC). \since 0.9.15 */
PA_SAMPLE_S24_32BE,
/**< Signed 24 Bit PCM in LSB of 32 Bit words, big endian. \since 0.9.15 */
PA_SAMPLE_MAX,
/**< Upper limit of valid sample types */
PA_SAMPLE_INVALID = -1
/**< An invalid value */
} pa_sample_format_t;
#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
/** Signed 32 Bit PCM, native endian */
#define PA_SAMPLE_S32NE PA_SAMPLE_S32BE
/** Signed 24 Bit PCM packed, native endian. \since 0.9.15 */
#define PA_SAMPLE_S24NE PA_SAMPLE_S24BE
/** Signed 24 Bit PCM in LSB of 32 Bit words, native endian. \since 0.9.15 */
#define PA_SAMPLE_S24_32NE PA_SAMPLE_S24_32BE
/** Signed 16 Bit PCM reverse endian */
#define PA_SAMPLE_S16RE PA_SAMPLE_S16LE
/** 32 Bit IEEE floating point, reverse endian */
#define PA_SAMPLE_FLOAT32RE PA_SAMPLE_FLOAT32LE
/** Signed 32 Bit PCM, reverse endian */
#define PA_SAMPLE_S32RE PA_SAMPLE_S32LE
/** Signed 24 Bit PCM, packed reverse endian. \since 0.9.15 */
#define PA_SAMPLE_S24RE PA_SAMPLE_S24LE
/** Signed 24 Bit PCM, in LSB of 32 Bit words, reverse endian. \since 0.9.15 */
#define PA_SAMPLE_S24_32RE PA_SAMPLE_S24_32LE
#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
/** Signed 32 Bit PCM, native endian */
#define PA_SAMPLE_S32NE PA_SAMPLE_S32LE
/** Signed 24 Bit PCM packed, native endian. \since 0.9.15 */
#define PA_SAMPLE_S24NE PA_SAMPLE_S24LE
/** Signed 24 Bit PCM in LSB of 32 Bit words, native endian. \since 0.9.15 */
#define PA_SAMPLE_S24_32NE PA_SAMPLE_S24_32LE
/** Signed 16 Bit PCM, reverse endian */
#define PA_SAMPLE_S16RE PA_SAMPLE_S16BE
/** 32 Bit IEEE floating point, reverse endian */
#define PA_SAMPLE_FLOAT32RE PA_SAMPLE_FLOAT32BE
/** Signed 32 Bit PCM, reverse endian */
#define PA_SAMPLE_S32RE PA_SAMPLE_S32BE
/** Signed 24 Bit PCM, packed reverse endian. \since 0.9.15 */
#define PA_SAMPLE_S24RE PA_SAMPLE_S24BE
/** Signed 24 Bit PCM, in LSB of 32 Bit words, reverse endian. \since 0.9.15 */
#define PA_SAMPLE_S24_32RE PA_SAMPLE_S24_32BE
#endif
/** A Shortcut for PA_SAMPLE_FLOAT32NE */
#define PA_SAMPLE_FLOAT32 PA_SAMPLE_FLOAT32NE
/** \cond fulldocs */
/* Allow clients to check with #ifdef for these sample formats */
#define PA_SAMPLE_U8 PA_SAMPLE_U8
#define PA_SAMPLE_ALAW PA_SAMPLE_ALAW
#define PA_SAMPLE_ULAW PA_SAMPLE_ULAW
#define PA_SAMPLE_S16LE PA_SAMPLE_S16LE
#define PA_SAMPLE_S16BE PA_SAMPLE_S16BE
#define PA_SAMPLE_FLOAT32LE PA_SAMPLE_FLOAT32LE
#define PA_SAMPLE_FLOAT32BE PA_SAMPLE_FLOAT32BE
#define PA_SAMPLE_S32LE PA_SAMPLE_S32LE
#define PA_SAMPLE_S32BE PA_SAMPLE_S32BE
#define PA_SAMPLE_S24LE PA_SAMPLE_S24LE
#define PA_SAMPLE_S24BE PA_SAMPLE_S24BE
#define PA_SAMPLE_S24_32LE PA_SAMPLE_S24_32LE
#define PA_SAMPLE_S24_32BE PA_SAMPLE_S24_32BE
/** \endcond */
/** A sample format and attribute specification */
typedef struct pa_sample_spec {
pa_sample_format_t format;
/**< The sample format */
uint32_t rate;
/**< The sample rate. (e.g. 44100) */
uint8_t channels;
/**< Audio channels. (1 for mono, 2 for stereo, ...) */
} pa_sample_spec;
/** Type for usec specifications (unsigned). Always 64 bit. */
typedef uint64_t pa_usec_t;
/** Return the amount of bytes playback of a second of audio with the specified sample type takes */
size_t pa_bytes_per_second(const pa_sample_spec *spec) PA_GCC_PURE;
/** Return the size of a frame with the specific sample type */
size_t pa_frame_size(const pa_sample_spec *spec) PA_GCC_PURE;
/** Return the size of a sample with the specific sample type */
size_t pa_sample_size(const pa_sample_spec *spec) PA_GCC_PURE;
/** Similar to pa_sample_size() but take a sample format instead of a
* full sample spec. \since 0.9.15 */
size_t pa_sample_size_of_format(pa_sample_format_t f) PA_GCC_PURE;
/** Calculate the time the specified bytes take to play with the
* specified sample type. The return value will always be rounded
* down for non-integral return values. */
pa_usec_t pa_bytes_to_usec(uint64_t length, const pa_sample_spec *spec) PA_GCC_PURE;
/** Calculates the number of bytes that are required for the specified
* time. The return value will always be rounded down for non-integral
* return values. \since 0.9 */
size_t pa_usec_to_bytes(pa_usec_t t, const pa_sample_spec *spec) PA_GCC_PURE;
/** Initialize the specified sample spec and return a pointer to
* it. The sample spec will have a defined state but
* pa_sample_spec_valid() will fail for it. \since 0.9.13 */
pa_sample_spec* pa_sample_spec_init(pa_sample_spec *spec);
/** Return non-zero if the given integer is a valid sample format. \since 5.0 */
int pa_sample_format_valid(unsigned format) PA_GCC_PURE;
/** Return non-zero if the rate is within the supported range. \since 5.0 */
int pa_sample_rate_valid(uint32_t rate) PA_GCC_PURE;
/** Return non-zero if the channel count is within the supported range.
* \since 5.0 */
int pa_channels_valid(uint8_t channels) PA_GCC_PURE;
/** Return non-zero when the sample type specification is valid */
int pa_sample_spec_valid(const pa_sample_spec *spec) PA_GCC_PURE;
/** Return non-zero when the two sample type specifications match */
int pa_sample_spec_equal(const pa_sample_spec*a, const pa_sample_spec*b) PA_GCC_PURE;
/** Return a descriptive string for the specified sample format. \since 0.8 */
const char *pa_sample_format_to_string(pa_sample_format_t f) PA_GCC_PURE;
/** Parse a sample format text. Inverse of pa_sample_format_to_string() */
pa_sample_format_t pa_parse_sample_format(const char *format) PA_GCC_PURE;
/** Maximum required string length for
* pa_sample_spec_snprint(). Please note that this value can change
* with any release without warning and without being considered API
* or ABI breakage. You should not use this definition anywhere where
* it might become part of an ABI. */
#define PA_SAMPLE_SPEC_SNPRINT_MAX 32
/** Pretty print a sample type specification to a string */
char* pa_sample_spec_snprint(char *s, size_t l, const pa_sample_spec *spec);
/** Maximum required string length for pa_bytes_snprint(). Please note
* that this value can change with any release without warning and
* without being considered API or ABI breakage. You should not use
* this definition anywhere where it might become part of an
* ABI. \since 0.9.16 */
#define PA_BYTES_SNPRINT_MAX 11
/** Pretty print a byte size value (i.e.\ "2.5 MiB") */
char* pa_bytes_snprint(char *s, size_t l, unsigned v);
/** Return 1 when the specified format is little endian, return -1
* when endianness does not apply to this format. \since 0.9.16 */
int pa_sample_format_is_le(pa_sample_format_t f) PA_GCC_PURE;
/** Return 1 when the specified format is big endian, return -1 when
* endianness does not apply to this format. \since 0.9.16 */
int pa_sample_format_is_be(pa_sample_format_t f) PA_GCC_PURE;
#ifdef WORDS_BIGENDIAN
#define pa_sample_format_is_ne(f) pa_sample_format_is_be(f)
#define pa_sample_format_is_re(f) pa_sample_format_is_le(f)
#else
/** Return 1 when the specified format is native endian, return -1
* when endianness does not apply to this format. \since 0.9.16 */
#define pa_sample_format_is_ne(f) pa_sample_format_is_le(f)
/** Return 1 when the specified format is reverse endian, return -1
* when endianness does not apply to this format. \since 0.9.16 */
#define pa_sample_format_is_re(f) pa_sample_format_is_be(f)
#endif
PA_C_DECL_END
#endif
|