/*** Copyright (c) 2002-2016, Erik de Castro Lopo <erikd@mega-nerd.com>** All rights reserved.**** This code is released under 2-clause BSD license. Please see the** file at : https://github.com/libsndfile/libsamplerate/blob/master/COPYING*/ /*** API documentation is available here:**     http://libsndfile.github.io/libsamplerate/api.html*/ #ifndef SAMPLERATE_H#define SAMPLERATE_H #ifdef __cplusplusextern "C" {#endif	/* __cplusplus */  /* Opaque data type SRC_STATE. */typedef struct SRC_STATE_tag SRC_STATE ; /* SRC_DATA is used to pass data to src_simple() and src_process(). */typedef struct{	const float	*data_in ;	float	*data_out ; 	long	input_frames, output_frames ;	long	input_frames_used, output_frames_gen ; 	int		end_of_input ; 	double	src_ratio ;} SRC_DATA ; /*** User supplied callback function type for use with src_callback_new()** and src_callback_read(). First parameter is the same pointer that was** passed into src_callback_new(). Second parameter is pointer to a** pointer. The user supplied callback function must modify *data to** point to the start of the user supplied float array. The user supplied** function must return the number of frames that **data points to.*/ typedef long (*src_callback_t) (void *cb_data, float **data) ; /***	Standard initialisation function : return an anonymous pointer to the**	internal state of the converter. Choose a converter from the enums below.**	Error returned in *error.*/ SRC_STATE* src_new (int converter_type, int channels, int *error) ; /*** Clone a handle : return an anonymous pointer to a new converter** containing the same internal state as orig. Error returned in *error.*/SRC_STATE* src_clone (SRC_STATE* orig, int *error) ; /***	Initilisation for callback based API : return an anonymous pointer to the**	internal state of the converter. Choose a converter from the enums below.**	The cb_data pointer can point to any data or be set to NULL. Whatever the**	value, when processing, user supplied function "func" gets called with**	cb_data as first parameter.*/ SRC_STATE* src_callback_new (src_callback_t func, int converter_type, int channels,				int *error, void* cb_data) ; /***	Cleanup all internal allocations.**	Always returns NULL.*/ SRC_STATE* src_delete (SRC_STATE *state) ; /***	Standard processing function.**	Returns non zero on error.*/ int src_process (SRC_STATE *state, SRC_DATA *data) ; /***	Callback based processing function. Read up to frames worth of data from**	the converter int *data and return frames read or -1 on error.*/long src_callback_read (SRC_STATE *state, double src_ratio, long frames, float *data) ; /***	Simple interface for performing a single conversion from input buffer to**	output buffer at a fixed conversion ratio.**	Simple interface does not require initialisation as it can only operate on**	a single buffer worth of audio.*/ int src_simple (SRC_DATA *data, int converter_type, int channels) ; /*** This library contains a number of different sample rate converters,** numbered 0 through N.**** Return a string giving either a name or a more full description of each** sample rate converter or NULL if no sample rate converter exists for** the given value. The converters are sequentially numbered from 0 to N.*/ const char *src_get_name (int converter_type) ;const char *src_get_description (int converter_type) ;const char *src_get_version (void) ; /***	Set a new SRC ratio. This allows step responses**	in the conversion ratio.**	Returns non zero on error.*/ int src_set_ratio (SRC_STATE *state, double new_ratio) ; /***	Get the current channel count.**	Returns negative on error, positive channel count otherwise*/ int src_get_channels (SRC_STATE *state) ; /***	Reset the internal SRC state.**	Does not modify the quality settings.**	Does not free any memory allocations.**	Returns non zero on error.*/ int src_reset (SRC_STATE *state) ; /*** Return TRUE if ratio is a valid conversion ratio, FALSE** otherwise.*/ int src_is_valid_ratio (double ratio) ; /***	Return an error number.*/ int src_error (SRC_STATE *state) ; /***	Convert the error number into a string.*/const char* src_strerror (int error) ; /*** The following enums can be used to set the interpolator type** using the function src_set_converter().*/ enum{	SRC_SINC_BEST_QUALITY		= 0,	SRC_SINC_MEDIUM_QUALITY		= 1,	SRC_SINC_FASTEST			= 2,	SRC_ZERO_ORDER_HOLD			= 3,	SRC_LINEAR					= 4,} ; /*** Extra helper functions for converting from short to float and** back again.*/ void src_short_to_float_array (const short *in, float *out, int len) ;void src_float_to_short_array (const float *in, short *out, int len) ; void src_int_to_float_array (const int *in, float *out, int len) ;void src_float_to_int_array (const float *in, int *out, int len) ;  #ifdef __cplusplus}		/* extern "C" */#endif	/* __cplusplus */ #endif	/* SAMPLERATE_H */