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Diffstat (limited to 'src/pulse/sample.h')
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diff --git a/src/pulse/sample.h b/src/pulse/sample.h new file mode 100644 index 0000000..35346a8 --- /dev/null +++ b/src/pulse/sample.h @@ -0,0 +1,364 @@ +#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 */ + + /* Remeber to update + * https://www.freedesktop.org/wiki/Software/PulseAudio/Documentation/User/SupportedAudioFormats/ + * when adding new formats! */ + + 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 that constitute playback of one second of + * audio, with the specified sample spec. */ +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 it would take to play a buffer of the specified + * size 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 size of a buffer required, for playback duration + * of the time specified, with the specified sample type. 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. Returns \a s. */ +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"). Returns \a s. */ +char* pa_bytes_snprint(char *s, size_t l, unsigned v); + +/** Returns 1 when the specified format is little endian, 0 when + * big endian. Returns -1 when endianness does not apply to the + * specified format, or endianess is unknown. \since 0.9.16 */ +int pa_sample_format_is_le(pa_sample_format_t f) PA_GCC_PURE; + +/** Returns 1 when the specified format is big endian, 0 when + * little endian. Returns -1 when endianness does not apply to the + * specified format, or endianess is unknown. \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 +/** Returns 1 when the specified format is native endian, 0 when + * not. Returns -1 when endianness does not apply to the + * specified format, or endianess is unknown. \since 0.9.16 */ +#define pa_sample_format_is_ne(f) pa_sample_format_is_le(f) +/** Returns 1 when the specified format is reverse endian, 0 when + * native. Returns -1 when endianness does not apply to the + * specified format, or endianess is unknown. \since 0.9.16 */ +#define pa_sample_format_is_re(f) pa_sample_format_is_be(f) +#endif + +PA_C_DECL_END + +#endif |