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/**********************************************************************
resample.h
Real-time library interface by Dominic Mazzoni
Based on resample-1.7:
http://www-ccrma.stanford.edu/~jos/resample/
License: LGPL - see the file LICENSE.txt for more information
**********************************************************************/
/*!
* \file
* \brief libresample API
* \author Dominic Mazzoni
*/
#ifndef LIBRESAMPLE_INCLUDED
#define LIBRESAMPLE_INCLUDED
#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */
/*!
* \brief Create a resampler
*
* \arg highQuality Set this argument to non-zero to enable higher quality
* resampling.
* \arg minFactor This is the minimum resampling factor that will be used for
* this resampler. The resampling factor is calculated in the following
* way: ( from sample rate / to sample rate ).
* \arg maxFactor This is the maximum resampling factor that will be used for
* this resampler.
*
* Use this function to create a new resampler that will maintain state
* information about the stream of audio being resampled.
*
* \return A handle to a new resampler
*/
void *resample_open(int highQuality,
double minFactor,
double maxFactor);
/*!
* \brief Duplicate a resampler
*
* \arg handle the resampler to duplicate
*
* \return A new handle to a resampler, initialized with the same parameters
* used to create the original resampler.
*/
void *resample_dup(const void *handle);
/*!
* \brief Get filter width for resampler
*
* \arg handle the resampler
*
* \return the filter width.
*/
int resample_get_filter_width(const void *handle);
/*!
* \brief Resample a chunk of audio
*
* \arg handle the resampler
* \arg factor the resampling factor. This factor should be calculated as
* ( from sample rate / to sample rate ). So, for converting from 8 kHz
* to 16 kHz, this value would be 2.0.
* \arg inBuffer the input buffer for audio to resample.
* \arg inBufferLen the number of samples in the input buffer
* \arg lastFlag Set this argument to non-zero if the data in the input buffer
* is known to be the end of a stream. This would be used if you're
* resampling a file, for example.
* \arg inBufferUsed This is an output parameter that indicates how many
* samples were consumed from the input buffer. Generally, this function
* is called in a loop until you know that the entire input buffer has
* been consumed, as it may take multiple calls to complete.
* \arg outBuffer This is the output buffer. This function will write the
* resampled audio into this buffer.
* \arg outBufferLen This parameter specifies how many samples there is room
* for in the output buffer.
*
* This is the main function used for resampling audio. It should be called
* in a loop until all of the data from the input buffer is consumed, or the
* output buffer has been filled.
*
* \return the number of samples written to the output buffer. If the return
* value is equal to the value provided in the outBufferLen parameter,
* then the output buffer has been filled.
*/
int resample_process(void *handle,
double factor,
float *inBuffer,
int inBufferLen,
int lastFlag,
int *inBufferUsed,
float *outBuffer,
int outBufferLen);
/*!
* \brief Close a resampler
*
* \arg handle the resampler to close
*
* Use this function to release a handle to a resampler that was created using
* either resample_open() or resample_dup().
*
* \return nothing.
*/
void resample_close(void *handle);
#ifdef __cplusplus
} /* extern "C" */
#endif /* __cplusplus */
#endif /* LIBRESAMPLE_INCLUDED */
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