code.delx.au - pulseaudio/blob - src/pulse/sample.h

   1 #ifndef foosamplehfoo
   2 #define foosamplehfoo
   3
   4 /***
   5   This file is part of PulseAudio.
   6
   7   Copyright 2004-2006 Lennart Poettering
   8   Copyright 2006 Pierre Ossman <ossman@cendio.se> for Cendio AB
   9
  10   PulseAudio is free software; you can redistribute it and/or modify
  11   it under the terms of the GNU Lesser General Public License as published
  12   by the Free Software Foundation; either version 2.1 of the License,
  13   or (at your option) any later version.
  14
  15   PulseAudio is distributed in the hope that it will be useful, but
  16   WITHOUT ANY WARRANTY; without even the implied warranty of
  17   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  18   General Public License for more details.
  19
  20   You should have received a copy of the GNU Lesser General Public License
  21   along with PulseAudio; if not, write to the Free Software
  22   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  23   USA.
  24 ***/
  25
  26 #include <inttypes.h>
  27 #include <sys/types.h>
  28 #include <sys/param.h>
  29 #include <math.h>
  30
  31 #include <pulse/gccmacro.h>
  32 #include <pulse/cdecl.h>
  33 #include <pulse/version.h>
  34
  35 /** \page sample Sample Format Specifications
  36  *
  37  * \section overv_sec Overview
  38  *
  39  * PulseAudio is capable of handling a multitude of sample formats, rates
  40  * and channels, transparently converting and mixing them as needed.
  41  *
  42  * \section format_sec Sample Format
  43  *
  44  * PulseAudio supports the following sample formats:
  45  *
  46  * \li PA_SAMPLE_U8 - Unsigned 8 bit integer PCM.
  47  * \li PA_SAMPLE_S16LE - Signed 16 integer bit PCM, little endian.
  48  * \li PA_SAMPLE_S16BE - Signed 16 integer bit PCM, big endian.
  49  * \li PA_SAMPLE_FLOAT32LE - 32 bit IEEE floating point PCM, little endian.
  50  * \li PA_SAMPLE_FLOAT32BE - 32 bit IEEE floating point PCM, big endian.
  51  * \li PA_SAMPLE_ALAW - 8 bit a-Law.
  52  * \li PA_SAMPLE_ULAW - 8 bit mu-Law.
  53  * \li PA_SAMPLE_S32LE - Signed 32 bit integer PCM, little endian.
  54  * \li PA_SAMPLE_S32BE - Signed 32 bit integer PCM, big endian.
  55  * \li PA_SAMPLE_S24LE - Signed 24 bit integer PCM packed, little endian.
  56  * \li PA_SAMPLE_S24BE - Signed 24 bit integer PCM packed, big endian.
  57  * \li PA_SAMPLE_S24_32LE - Signed 24 bit integer PCM in LSB of 32 bit words, little endian.
  58  * \li PA_SAMPLE_S24_32BE - Signed 24 bit integer PCM in LSB of 32 bit words, big endian.
  59  *
  60  * The floating point sample formats have the range from -1.0 to 1.0.
  61  *
  62  * The sample formats that are sensitive to endianness have convenience
  63  * macros for native endian (NE), and reverse endian (RE).
  64  *
  65  * \section rate_sec Sample Rates
  66  *
  67  * PulseAudio supports any sample rate between 1 Hz and 192000 Hz. There is no
  68  * point trying to exceed the sample rate of the output device though as the
  69  * signal will only get downsampled, consuming CPU on the machine running the
  70  * server.
  71  *
  72  * \section chan_sec Channels
  73  *
  74  * PulseAudio supports up to 32 individual channels. The order of the
  75  * channels is up to the application, but they must be continous. To map
  76  * channels to speakers, see \ref channelmap.
  77  *
  78  * \section calc_sec Calculations
  79  *
  80  * The PulseAudio library contains a number of convenience functions to do
  81  * calculations on sample formats:
  82  *
  83  * \li pa_bytes_per_second() - The number of bytes one second of audio will
  84  *                             take given a sample format.
  85  * \li pa_frame_size() - The size, in bytes, of one frame (i.e. one set of
  86  *                       samples, one for each channel).
  87  * \li pa_sample_size() - The size, in bytes, of one sample.
  88  * \li pa_bytes_to_usec() - Calculate the time it would take to play a buffer
  89  *                          of a certain size.
  90  *
  91  * \section util_sec Convenience Functions
  92  *
  93  * The library also contains a couple of other convenience functions:
  94  *
  95  * \li pa_sample_spec_valid() - Tests if a sample format specification is
  96  *                              valid.
  97  * \li pa_sample_spec_equal() - Tests if the sample format specifications are
  98  *                              identical.
  99  * \li pa_sample_format_to_string() - Return a textual description of a
 100  *                                    sample format.
 101  * \li pa_parse_sample_format() - Parse a text string into a sample format.
 102  * \li pa_sample_spec_snprint() - Create a textual description of a complete
 103  *                                 sample format specification.
 104  * \li pa_bytes_snprint() - Pretty print a byte value (e.g. 2.5 MiB).
 105  */
 106
 107 /** \file
 108  * Constants and routines for sample type handling
 109  *
 110  * See also \subpage sample
 111  */
 112
 113 PA_C_DECL_BEGIN
 114
 115 #if !defined(WORDS_BIGENDIAN)
 116 #if defined(__BYTE_ORDER)
 117 #if __BYTE_ORDER == __BIG_ENDIAN
 118 #define WORDS_BIGENDIAN
 119 #endif
 120 #endif
 121 #endif
 122
 123 /** Maximum number of allowed channels */
 124 #define PA_CHANNELS_MAX 32U
 125
 126 /** Maximum allowed sample rate */
 127 #define PA_RATE_MAX (48000U*4U)
 128
 129 /** Sample format */
 130 typedef enum pa_sample_format {
 131     PA_SAMPLE_U8,
 132     /**< Unsigned 8 Bit PCM */
 133
 134     PA_SAMPLE_ALAW,
 135     /**< 8 Bit a-Law */
 136
 137     PA_SAMPLE_ULAW,
 138     /**< 8 Bit mu-Law */
 139
 140     PA_SAMPLE_S16LE,
 141     /**< Signed 16 Bit PCM, little endian (PC) */
 142
 143     PA_SAMPLE_S16BE,
 144     /**< Signed 16 Bit PCM, big endian */
 145
 146     PA_SAMPLE_FLOAT32LE,
 147     /**< 32 Bit IEEE floating point, little endian (PC), range -1.0 to 1.0 */
 148
 149     PA_SAMPLE_FLOAT32BE,
 150     /**< 32 Bit IEEE floating point, big endian, range -1.0 to 1.0 */
 151
 152     PA_SAMPLE_S32LE,
 153     /**< Signed 32 Bit PCM, little endian (PC) */
 154
 155     PA_SAMPLE_S32BE,
 156     /**< Signed 32 Bit PCM, big endian */
 157
 158     PA_SAMPLE_S24LE,
 159     /**< Signed 24 Bit PCM packed, little endian (PC). \since 0.9.15 */
 160
 161     PA_SAMPLE_S24BE,
 162     /**< Signed 24 Bit PCM packed, big endian. \since 0.9.15 */
 163
 164     PA_SAMPLE_S24_32LE,
 165     /**< Signed 24 Bit PCM in LSB of 32 Bit words, little endian (PC). \since 0.9.15 */
 166
 167     PA_SAMPLE_S24_32BE,
 168     /**< Signed 24 Bit PCM in LSB of 32 Bit words, big endian. \since 0.9.15 */
 169
 170     PA_SAMPLE_MAX,
 171     /**< Upper limit of valid sample types */
 172
 173     PA_SAMPLE_INVALID = -1
 174     /**< An invalid value */
 175 } pa_sample_format_t;
 176
 177 #ifdef WORDS_BIGENDIAN
 178 /** Signed 16 Bit PCM, native endian */
 179 #define PA_SAMPLE_S16NE PA_SAMPLE_S16BE
 180 /** 32 Bit IEEE floating point, native endian */
 181 #define PA_SAMPLE_FLOAT32NE PA_SAMPLE_FLOAT32BE
 182 /** Signed 32 Bit PCM, native endian */
 183 #define PA_SAMPLE_S32NE PA_SAMPLE_S32BE
 184 /** Signed 24 Bit PCM packed, native endian. \since 0.9.15 */
 185 #define PA_SAMPLE_S24NE PA_SAMPLE_S24BE
 186 /** Signed 24 Bit PCM in LSB of 32 Bit words, native endian. \since 0.9.15 */
 187 #define PA_SAMPLE_S24_32NE PA_SAMPLE_S24_32BE
 188
 189 /** Signed 16 Bit PCM reverse endian */
 190 #define PA_SAMPLE_S16RE PA_SAMPLE_S16LE
 191 /** 32 Bit IEEE floating point, reverse endian */
 192 #define PA_SAMPLE_FLOAT32RE PA_SAMPLE_FLOAT32LE
 193 /** Signed 32 Bit PCM, reverse endian */
 194 #define PA_SAMPLE_S32RE PA_SAMPLE_S32LE
 195 /** Signed 24 Bit PCM, packed reverse endian. \since 0.9.15 */
 196 #define PA_SAMPLE_S24RE PA_SAMPLE_S24LE
 197 /** Signed 24 Bit PCM, in LSB of 32 Bit words, reverse endian. \since 0.9.15 */
 198 #define PA_SAMPLE_S24_32RE PA_SAMPLE_S24_32LE
 199 #else
 200 /** Signed 16 Bit PCM, native endian */
 201 #define PA_SAMPLE_S16NE PA_SAMPLE_S16LE
 202 /** 32 Bit IEEE floating point, native endian */
 203 #define PA_SAMPLE_FLOAT32NE PA_SAMPLE_FLOAT32LE
 204 /** Signed 32 Bit PCM, native endian */
 205 #define PA_SAMPLE_S32NE PA_SAMPLE_S32LE
 206 /** Signed 24 Bit PCM packed, native endian. \since 0.9.15 */
 207 #define PA_SAMPLE_S24NE PA_SAMPLE_S24LE
 208 /** Signed 24 Bit PCM in LSB of 32 Bit words, native endian. \since 0.9.15 */
 209 #define PA_SAMPLE_S24_32NE PA_SAMPLE_S24_32LE
 210
 211 /** Signed 16 Bit PCM, reverse endian */
 212 #define PA_SAMPLE_S16RE PA_SAMPLE_S16BE
 213 /** 32 Bit IEEE floating point, reverse endian */
 214 #define PA_SAMPLE_FLOAT32RE PA_SAMPLE_FLOAT32BE
 215 /** Signed 32 Bit PCM, reverse endian */
 216 #define PA_SAMPLE_S32RE PA_SAMPLE_S32BE
 217 /** Signed 24 Bit PCM, packed reverse endian. \since 0.9.15 */
 218 #define PA_SAMPLE_S24RE PA_SAMPLE_S24BE
 219 /** Signed 24 Bit PCM, in LSB of 32 Bit words, reverse endian. \since 0.9.15 */
 220 #define PA_SAMPLE_S24_32RE PA_SAMPLE_S24_32BE
 221 #endif
 222
 223 /** A Shortcut for PA_SAMPLE_FLOAT32NE */
 224 #define PA_SAMPLE_FLOAT32 PA_SAMPLE_FLOAT32NE
 225
 226 /** \cond fulldocs */
 227 /* Allow clients to check with #ifdef for these sample formats */
 228 #define PA_SAMPLE_U8 PA_SAMPLE_U8
 229 #define PA_SAMPLE_ALAW PA_SAMPLE_ALAW
 230 #define PA_SAMPLE_ULAW PA_SAMPLE_ULAW
 231 #define PA_SAMPLE_S16LE PA_SAMPLE_S16LE
 232 #define PA_SAMPLE_S16BE PA_SAMPLE_S16BE
 233 #define PA_SAMPLE_FLOAT32LE PA_SAMPLE_FLOAT32LE
 234 #define PA_SAMPLE_FLOAT32BE PA_SAMPLE_FLOAT32BE
 235 #define PA_SAMPLE_S32LE PA_SAMPLE_S32LE
 236 #define PA_SAMPLE_S32BE PA_SAMPLE_S32BE
 237 #define PA_SAMPLE_S24LE PA_SAMPLE_S24LE
 238 #define PA_SAMPLE_S24BE PA_SAMPLE_S24BE
 239 #define PA_SAMPLE_S24_32LE PA_SAMPLE_S24_32LE
 240 #define PA_SAMPLE_S24_32BE PA_SAMPLE_S24_32BE
 241 /** \endcond */
 242
 243 /** A sample format and attribute specification */
 244 typedef struct pa_sample_spec {
 245     pa_sample_format_t format;
 246     /**< The sample format */
 247
 248     uint32_t rate;
 249     /**< The sample rate. (e.g. 44100) */
 250
 251     uint8_t channels;
 252     /**< Audio channels. (1 for mono, 2 for stereo, ...) */
 253 } pa_sample_spec;
 254
 255 /** Type for usec specifications (unsigned). Always 64 bit. */
 256 typedef uint64_t pa_usec_t;
 257
 258 /** Return the amount of bytes playback of a second of audio with the specified sample type takes */
 259 size_t pa_bytes_per_second(const pa_sample_spec *spec) PA_GCC_PURE;
 260
 261 /** Return the size of a frame with the specific sample type */
 262 size_t pa_frame_size(const pa_sample_spec *spec) PA_GCC_PURE;
 263
 264 /** Return the size of a sample with the specific sample type */
 265 size_t pa_sample_size(const pa_sample_spec *spec) PA_GCC_PURE;
 266
 267 /** Similar to pa_sample_size() but take a sample format instead of a
 268  * full sample spec. \since 0.9.15 */
 269 size_t pa_sample_size_of_format(pa_sample_format_t f) PA_GCC_PURE;
 270
 271 /** Calculate the time the specified bytes take to play with the
 272  * specified sample type. The return value will always be rounded
 273  * down for non-integral return values. */
 274 pa_usec_t pa_bytes_to_usec(uint64_t length, const pa_sample_spec *spec) PA_GCC_PURE;
 275
 276 /** Calculates the number of bytes that are required for the specified
 277  * time. The return value will always be rounded down for non-integral
 278  * return values. \since 0.9 */
 279 size_t pa_usec_to_bytes(pa_usec_t t, const pa_sample_spec *spec) PA_GCC_PURE;
 280
 281 /** Initialize the specified sample spec and return a pointer to
 282  * it. The sample spec will have a defined state but
 283  * pa_sample_spec_valid() will fail for it. \since 0.9.13 */
 284 pa_sample_spec* pa_sample_spec_init(pa_sample_spec *spec);
 285
 286 /** Return non-zero when the sample type specification is valid */
 287 int pa_sample_spec_valid(const pa_sample_spec *spec) PA_GCC_PURE;
 288
 289 /** Return non-zero when the two sample type specifications match */
 290 int pa_sample_spec_equal(const pa_sample_spec*a, const pa_sample_spec*b) PA_GCC_PURE;
 291
 292 /** Return a descriptive string for the specified sample format. \since 0.8 */
 293 const char *pa_sample_format_to_string(pa_sample_format_t f) PA_GCC_PURE;
 294
 295 /** Parse a sample format text. Inverse of pa_sample_format_to_string() */
 296 pa_sample_format_t pa_parse_sample_format(const char *format) PA_GCC_PURE;
 297
 298 /** Maximum required string length for
 299  * pa_sample_spec_snprint(). Please note that this value can change
 300  * with any release without warning and without being considered API
 301  * or ABI breakage. You should not use this definition anywhere where
 302  * it might become part of an ABI. */
 303 #define PA_SAMPLE_SPEC_SNPRINT_MAX 32
 304
 305 /** Pretty print a sample type specification to a string */
 306 char* pa_sample_spec_snprint(char *s, size_t l, const pa_sample_spec *spec);
 307
 308 /** Maximum required string length for pa_bytes_snprint(). Please note
 309  * that this value can change with any release without warning and
 310  * without being considered API or ABI breakage. You should not use
 311  * this definition anywhere where it might become part of an
 312  * ABI. \since 0.9.16 */
 313 #define PA_BYTES_SNPRINT_MAX 11
 314
 315 /** Pretty print a byte size value. (i.e. "2.5 MiB") */
 316 char* pa_bytes_snprint(char *s, size_t l, unsigned v);
 317
 318 /** Return 1 when the specified format is little endian, return -1
 319  * when endianess does not apply to this format. \since 0.9.16 */
 320 int pa_sample_format_is_le(pa_sample_format_t f) PA_GCC_PURE;
 321
 322 /** Return 1 when the specified format is big endian, return -1 when
 323  * endianess does not apply to this format. \since 0.9.16 */
 324 int pa_sample_format_is_be(pa_sample_format_t f) PA_GCC_PURE;
 325
 326 #ifdef WORDS_BIGENDIAN
 327 #define pa_sample_format_is_ne(f) pa_sample_format_is_be(f)
 328 #define pa_sample_format_is_re(f) pa_sample_format_is_le(f)
 329 #else
 330 /** Return 1 when the specified format is native endian, return -1
 331  * when endianess does not apply to this format. \since 0.9.16 */
 332 #define pa_sample_format_is_ne(f) pa_sample_format_is_le(f)
 333 /** Return 1 when the specified format is reverse endian, return -1
 334  * when endianess does not apply to this format. \since 0.9.16 */
 335 #define pa_sample_format_is_re(f) pa_sample_format_is_be(f)
 336 #endif
 337
 338 PA_C_DECL_END
 339
 340 #endif