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API documentation for libmpg123, libout123, and libsyn123

Note: This API doc is automatically generated from the current development version that you can get via Subversion or as a daily snapshot from http://mpg123.org/snapshot. There may be differences (additions) compared to the latest stable release. See NEWS.libmpg123, NEWS.libout123, NEWS.libsyn123, and the overall NEWS file on libmpg123 versions and important changes between them.
Let me emphasize that the policy for the lib*123 family is to always stay backwards compatible -- only additions are planned (and it's not yet planned to change the plans;-).
Go to the documentation of this file.
 /*
     syn123: some audio signal synthesis and format conversion
  
     copyright 2017-2023 by the mpg123 project,
     free software under the terms of the LGPL 2.1
     see COPYING and AUTHORS files in distribution or http://mpg123.org
  
     initially written by Thomas Orgis
  
     Consider defining SYN123_PORTABLE_API to limit the definitions to
     a safer subset without some problematic features (mainly off_t usage).
 */
  
 #ifndef SYN123_H
 #define SYN123_H
  
 /* Common audio encoding specification. */
 #include "fmt123.h"
  
 #define SYN123_API_VERSION 2
 #define SYN123_PATCHLEVEL  3
  
 #ifndef MPG123_EXPORT
 #ifdef BUILD_MPG123_DLL
 /* The dll exports. */
 #define MPG123_EXPORT __declspec(dllexport)
 #else
 #ifdef LINK_MPG123_DLL
 /* The exe imports. */
 #define MPG123_EXPORT __declspec(dllimport)
 #else
 /* Nothing on normal/UNIX builds */
 #define MPG123_EXPORT
 #endif
 #endif
 #endif
  
 #ifndef MPG123_RESTRICT
 #if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L
 #define MPG123_RESTRICT restrict
 #else
 #define MPG123_RESTRICT
 #endif
 #endif
  
 // for off_t and ssize_t
 #ifndef SYN123_PORTABLE_API
 #include <sys/types.h>
 #endif
  
 #include <stddef.h>
 #include <stdint.h>
  
 #ifdef __cplusplus
 extern "C" {
 #endif
  
 struct syn123_struct;
 typedef struct syn123_struct syn123_handle;
  
 MPG123_EXPORT
 const char *syn123_distversion(unsigned int *major, unsigned int *minor, unsigned int *patch);
  
 MPG123_EXPORT
 unsigned int syn123_libversion(unsigned int *patch);
  
 enum syn123_error
 {
     SYN123_OK = 0   
 ,   SYN123_BAD_HANDLE 
 ,   SYN123_BAD_FMT  
 ,   SYN123_BAD_ENC  
 ,   SYN123_BAD_CONV 
 ,   SYN123_BAD_SIZE 
 ,   SYN123_BAD_BUF  
 ,   SYN123_BAD_CHOP 
 ,   SYN123_DOOM     
 ,   SYN123_WEIRD    
 ,   SYN123_BAD_FREQ 
 ,   SYN123_BAD_SWEEP 
 ,   SYN123_OVERFLOW  
 ,   SYN123_NO_DATA   
 ,   SYN123_BAD_DATA  
 };
  
 const char* syn123_strerror(int errcode);
  
 MPG123_EXPORT
 syn123_handle* syn123_new( long rate, int channels, int encoding
 ,   size_t maxbuf, int *err );
  
 MPG123_EXPORT
 void syn123_del(syn123_handle *sh);
  
 MPG123_EXPORT
 int syn123_dither(syn123_handle *sh, int dither, unsigned long *seed);
  
 MPG123_EXPORT
 size_t syn123_read(syn123_handle *sh, void *dst, size_t dst_bytes);
  
 enum syn123_wave_id
 {
     SYN123_WAVE_INVALID = -1 
 ,   SYN123_WAVE_FLAT = 0 
 ,   SYN123_WAVE_SINE     
 ,   SYN123_WAVE_SQUARE   
 ,   SYN123_WAVE_TRIANGLE 
 ,   SYN123_WAVE_SAWTOOTH 
 ,   SYN123_WAVE_GAUSS    
 ,   SYN123_WAVE_PULSE    
 ,   SYN123_WAVE_SHOT     
 ,   SYN123_WAVE_LIMIT 
 };
  
 MPG123_EXPORT
 int syn123_setup_waves( syn123_handle* sh, size_t count
 ,   int *id, double *freq, double *phase, int* backwards
 ,   size_t *period );
  
 MPG123_EXPORT
 int syn123_query_waves( syn123_handle* sh, size_t *count
 ,   int *id, double *freq, double *phase, int* backwards
 ,   size_t *period );
  
 MPG123_EXPORT
 const char* syn123_wave_name(int id);
  
 MPG123_EXPORT
 int syn123_wave_id(const char *name);
  
 enum syn123_sweep_id
 {
     SYN123_SWEEP_LIN = 0 
 ,   SYN123_SWEEP_QUAD    
 ,   SYN123_SWEEP_EXP     
 ,   SYN123_SWEEP_LIMIT   
 };
  
 MPG123_EXPORT
 int syn123_setup_sweep( syn123_handle* sh
 ,   int wave_id, double phase, int backwards
 ,   int sweep_id, double *f1, double *f2, int smooth, size_t duration
 ,   double *endphase, size_t *period, size_t *buffer_period );
  
 MPG123_EXPORT
 int syn123_setup_pink( syn123_handle *sh, int rows, unsigned long seed
 ,   size_t *period );
  
 MPG123_EXPORT
 int syn123_setup_white(syn123_handle *sh, unsigned long seed, size_t *period);
  
 MPG123_EXPORT
 int syn123_setup_geiger( syn123_handle *sh, double activity
 ,   unsigned long seed, size_t *period );
  
 MPG123_EXPORT
 int syn123_setup_silence(syn123_handle *sh);
  
 MPG123_EXPORT
 int syn123_conv( void * MPG123_RESTRICT dst, int dst_enc, size_t dst_size
 ,   void * MPG123_RESTRICT src, int src_enc, size_t src_bytes
 ,   size_t *dst_bytes, size_t *clipped, syn123_handle * sh );
  
 #define SYN123_DB_LIMIT 500
  
 MPG123_EXPORT double syn123_db2lin(double db);
  
 MPG123_EXPORT double syn123_lin2db(double volume);
  
 MPG123_EXPORT
 int syn123_amp( void* buf, int encoding, size_t samples
 ,   double volume, double offset,   size_t *clipped, syn123_handle *sh );
  
 MPG123_EXPORT
 size_t syn123_clip(void *buf, int encoding, size_t samples);
  
 MPG123_EXPORT
 size_t syn123_soft_clip( void *buf, int encoding, size_t samples
 ,   double limit, double width, syn123_handle *sh );
  
 MPG123_EXPORT
 void syn123_interleave( void * MPG123_RESTRICT dst, void** MPG123_RESTRICT src
 ,   int channels, size_t samplesize, size_t samplecount );
  
 MPG123_EXPORT
 void syn123_deinterleave( void ** MPG123_RESTRICT dst, void * MPG123_RESTRICT src
 ,   int channels, size_t samplesize, size_t samplecount );
  
 MPG123_EXPORT
 void syn123_mono2many( void * MPG123_RESTRICT dst, void * MPG123_RESTRICT src
 , int channels, size_t samplesize, size_t samplecount );
  
 #define SYN123_IOFF(sample, channel, channels) ((sample)*(channels)+(channel))
  
 MPG123_EXPORT
 int syn123_mixenc(int src_enc, int dst_enc);
  
 MPG123_EXPORT
 int syn123_mix( void * MPG123_RESTRICT dst, int dst_enc, int dst_channels
 ,   void * MPG123_RESTRICT src, int src_enc, int src_channels
 ,   const double * mixmatrix
 ,   size_t samples, int silence, size_t *clipped, syn123_handle *sh );
  
 MPG123_EXPORT
 int syn123_setup_filter( syn123_handle *sh
 ,   int append, unsigned int order, double *b, double *a
 ,   int mixenc, int channels, int init_firstval );
  
 MPG123_EXPORT
 int syn123_query_filter( syn123_handle *sh, size_t position
 ,   size_t *count, unsigned int *order, double *b, double *a
 ,   int *mixenc, int *channels, int *init_firstval );
  
 MPG123_EXPORT
 void syn123_drop_filter(syn123_handle *sh, size_t count);
  
 MPG123_EXPORT
 int syn123_filter( syn123_handle *sh
 ,   void* buf, int encoding, size_t samples );
  
 MPG123_EXPORT
 int syn123_setup_resample( syn123_handle *sh, long inrate, long outrate
 ,   int channels, int dirty, int smooth );
  
 MPG123_EXPORT
 long syn123_resample_maxrate(void);
  
 MPG123_EXPORT
 size_t syn123_resample_count(long inrate, long outrate, size_t ins);
  
 MPG123_EXPORT
 size_t syn123_resample_history(long inrate, long outrate, int dirty);
  
 MPG123_EXPORT
 size_t syn123_resample_incount(long input_rate, long output_rate, size_t outs);
  
 MPG123_EXPORT
 size_t syn123_resample_fillcount(long input_rate, long output_rate, size_t outs);
  
  
 MPG123_EXPORT
 size_t syn123_resample_maxincount(long input_rate, long output_rate);
  
 MPG123_EXPORT
 size_t syn123_resample_out(syn123_handle *sh, size_t ins, int *err);
  
 MPG123_EXPORT
 size_t syn123_resample_in(syn123_handle *sh, size_t outs, int *err);
  
 MPG123_EXPORT
 int64_t syn123_resample_total64(long inrate, long outrate, int64_t ins);
  
 MPG123_EXPORT
 int64_t syn123_resample_intotal64(long inrate, long outrate, int64_t outs);
  
 MPG123_EXPORT
 size_t syn123_resample( syn123_handle *sh,
     float * MPG123_RESTRICT dst, float * MPG123_RESTRICT src, size_t samples );
  
 MPG123_EXPORT
 void syn123_swap_bytes(void* buf, size_t samplesize, size_t samplecount);
  
 /* Wrappers over the above to convert to/from syn123's native byte order
    from/to little or big endian. */
  
 MPG123_EXPORT
 void syn123_host2le(void *buf, size_t samplesize, size_t samplecount);
  
 MPG123_EXPORT
 void syn123_host2be(void *buf, size_t samplesize, size_t samplecount);
  
 MPG123_EXPORT
 void syn123_le2host(void *buf, size_t samplesize, size_t samplecount);
  
 MPG123_EXPORT
 void syn123_be2host(void *buf, size_t samplesize, size_t samplecount);
  
 // You are invited to defined SYN123_PORTABLE_API to avoid seeing shape-shifting off_t
 // anywhere, also to avoid using non-standard types like ssize_t.
 #if !defined(SYN123_PORTABLE_API) && !defined(SYN123_NO_LARGEFUNC)
  
 /* A little hack to help MSVC not having ssize_t, duplicated in internal header. */
 #ifdef _MSC_VER
 #include <stddef.h>
 typedef ptrdiff_t syn123_ssize_t;
 #else
 typedef ssize_t syn123_ssize_t;
 #endif
  
 MPG123_EXPORT
 syn123_ssize_t syn123_resample_expect(syn123_handle *sh, size_t ins);
  
 MPG123_EXPORT
 syn123_ssize_t syn123_resample_inexpect(syn123_handle *sh, size_t outs);
  
 /* Lightweight large file hackery to enable worry-reduced use of off_t.
    Depending on the size of off_t in your client build, the corresponding
    library function needs to be chosen. */
  
 #if defined(_FILE_OFFSET_BITS) && !defined(MPG123_NO_LARGENAME)
 #  if _FILE_OFFSET_BITS+0 == 32
 #    define syn123_resample_total   syn123_resample_total_32
 #    define syn123_resample_intotal syn123_resample_intotal_32
 #  elif _FILE_OFFSET_BITS+0 == 64
 #    define syn123_resample_total   syn123_resample_total_64
 #    define syn123_resample_intotal syn123_resample_intotal_64
 #  else
 #    error "Unpredicted _FILE_OFFSET_BITS value."
 #  endif
 #endif
  
 MPG123_EXPORT
 off_t syn123_resample_total(long inrate, long outrate, off_t ins);
  
 MPG123_EXPORT
 off_t syn123_resample_intotal(long inrate, long outrate, off_t outs);
  
 #endif
  
 #ifdef __cplusplus
 }
 #endif
  
 #endif