188 lines
6.3 KiB
C
188 lines
6.3 KiB
C
/*
|
|
* FreeSWITCH Modular Media Switching Software Library / Soft-Switch Application
|
|
* Copyright (C) 2005-2012, Anthony Minessale II <anthm@freeswitch.org>
|
|
*
|
|
* Version: MPL 1.1
|
|
*
|
|
* The contents of this file are subject to the Mozilla Public License Version
|
|
* 1.1 (the "License"); you may not use this file except in compliance with
|
|
* the License. You may obtain a copy of the License at
|
|
* http://www.mozilla.org/MPL/
|
|
*
|
|
* Software distributed under the License is distributed on an "AS IS" basis,
|
|
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
|
|
* for the specific language governing rights and limitations under the
|
|
* License.
|
|
*
|
|
* The Original Code is FreeSWITCH Modular Media Switching Software Library / Soft-Switch Application
|
|
*
|
|
* The Initial Developer of the Original Code is
|
|
* Anthony Minessale II <anthm@freeswitch.org>
|
|
* Portions created by the Initial Developer are Copyright (C)
|
|
* the Initial Developer. All Rights Reserved.
|
|
*
|
|
* Contributor(s):
|
|
*
|
|
* Anthony Minessale II <anthm@freeswitch.org>
|
|
*
|
|
*
|
|
* switch_caller.h -- Caller Identification
|
|
*
|
|
*/
|
|
/*! \file switch_resample.h
|
|
\brief Audio Resample Code
|
|
|
|
This module implements a generic interface for doing audio resampling it currently uses libresample but can be ported to
|
|
any resample library with a little effort. I decided against making this interface pluggable because there are not many
|
|
options in terms of resample libraries so it seemed like a waste but I did opt to frontend the interface in case a better
|
|
way comes along some day. =D
|
|
|
|
*/
|
|
#define switch_normalize_volume(x) if (x > 4) x = 4; if (x < -4) x = -4;
|
|
#define switch_normalize_volume_granular(x) if (x > 12) x = 12; if (x < -12) x = -12;
|
|
|
|
#ifndef SWITCH_RESAMPLE_H
|
|
#define SWITCH_RESAMPLE_H
|
|
#define SWITCH_RESAMPLE_QUALITY 2
|
|
#include <switch.h>
|
|
SWITCH_BEGIN_EXTERN_C
|
|
/*!
|
|
\defgroup resamp Audio Resample Functions
|
|
\ingroup core1
|
|
\{
|
|
*/
|
|
/*! \brief An audio resampling handle */
|
|
typedef struct {
|
|
/*! a pointer to store the resampler object */
|
|
void *resampler;
|
|
/*! the rate to resample from in hz */
|
|
int from_rate;
|
|
/*! the rate to resample to in hz */
|
|
int to_rate;
|
|
/*! the factor to resample by (from / to) */
|
|
double factor;
|
|
double rfactor;
|
|
int16_t *to;
|
|
/*! the size of the to buffer used */
|
|
uint32_t to_len;
|
|
/*! the total size of the to buffer */
|
|
uint32_t to_size;
|
|
|
|
} switch_audio_resampler_t;
|
|
|
|
/*!
|
|
\brief Prepare a new resampler handle
|
|
\param new_resampler NULL pointer to aim at the new handle
|
|
\param from_rate the rate to transfer from in hz
|
|
\param to_rate the rate to transfer to in hz
|
|
\param quality the quality desired
|
|
\return SWITCH_STATUS_SUCCESS if the handle was created
|
|
*/
|
|
SWITCH_DECLARE(switch_status_t) switch_resample_perform_create(switch_audio_resampler_t **new_resampler,
|
|
uint32_t from_rate, uint32_t to_rate, uint32_t to_size,
|
|
int quality, uint32_t channels, const char *file, const char *func, int line);
|
|
|
|
|
|
#define switch_resample_create(_n, _fr, _tr, _ts, _q, _c) switch_resample_perform_create(_n, _fr, _tr, _ts, _q, _c, __FILE__, __SWITCH_FUNC__, __LINE__)
|
|
|
|
/*!
|
|
\brief Destroy an existing resampler handle
|
|
\param resampler the resampler handle to destroy
|
|
*/
|
|
SWITCH_DECLARE(void) switch_resample_destroy(switch_audio_resampler_t **resampler);
|
|
|
|
/*!
|
|
\brief Resample one float buffer into another using specifications of a given handle
|
|
\param resampler the resample handle
|
|
\param src the source data
|
|
\param srclen the length of the source data
|
|
\return the used size of dst
|
|
*/
|
|
SWITCH_DECLARE(uint32_t) switch_resample_process(switch_audio_resampler_t *resampler, int16_t *src, uint32_t srclen);
|
|
|
|
|
|
/*!
|
|
\brief Convert an array of floats to an array of shorts
|
|
\param f the float buffer
|
|
\param s the short buffer
|
|
\param len the length of the buffers
|
|
\return the size of the converted buffer
|
|
*/
|
|
SWITCH_DECLARE(switch_size_t) switch_float_to_short(float *f, short *s, switch_size_t len);
|
|
|
|
/*!
|
|
\brief Convert an array of chars to an array of floats
|
|
\param c the char buffer
|
|
\param f the float buffer
|
|
\param len the length of the buffers
|
|
\return the size of the converted buffer
|
|
*/
|
|
SWITCH_DECLARE(int) switch_char_to_float(char *c, float *f, int len);
|
|
|
|
/*!
|
|
\brief Convert an array of floats to an array of chars
|
|
\param f an array of floats
|
|
\param c an array of chars
|
|
\param len the length of the buffers
|
|
\return the size of the converted buffer
|
|
*/
|
|
SWITCH_DECLARE(int) switch_float_to_char(float *f, char *c, int len);
|
|
|
|
/*!
|
|
\brief Convert an array of shorts to an array of floats
|
|
\param s an array of shorts
|
|
\param f an array of floats
|
|
\param len the size of the buffers
|
|
\return the size of the converted buffer
|
|
*/
|
|
SWITCH_DECLARE(int) switch_short_to_float(short *s, float *f, int len);
|
|
|
|
/*!
|
|
\brief Perform a byteswap on a buffer of 16 bit samples
|
|
\param buf an array of samples
|
|
\param len the size of the array
|
|
*/
|
|
SWITCH_DECLARE(void) switch_swap_linear(int16_t *buf, int len);
|
|
|
|
/*!
|
|
\brief Generate static noise
|
|
\param data the audio data buffer
|
|
\param samples the number of 2 byte samples
|
|
\param divisor the volume factor
|
|
*/
|
|
SWITCH_DECLARE(void) switch_generate_sln_silence(int16_t *data, uint32_t samples, uint32_t divisor);
|
|
|
|
/*!
|
|
\brief Change the volume of a signed linear audio frame
|
|
\param data the audio data
|
|
\param samples the number of 2 byte samples
|
|
\param vol the volume factor -4 -> 4
|
|
*/
|
|
SWITCH_DECLARE(void) switch_change_sln_volume(int16_t *data, uint32_t samples, int32_t vol);
|
|
|
|
/*!
|
|
\brief Change the volume of a signed linear audio frame with more granularity
|
|
\param data the audio data
|
|
\param samples the number of 2 byte samples
|
|
\param vol the volume factor -12 -> 12
|
|
*/
|
|
SWITCH_DECLARE(void) switch_change_sln_volume_granular(int16_t *data, uint32_t samples, int32_t vol);
|
|
///\}
|
|
|
|
SWITCH_DECLARE(uint32_t) switch_merge_sln(int16_t *data, uint32_t samples, int16_t *other_data, uint32_t other_samples);
|
|
SWITCH_DECLARE(uint32_t) switch_unmerge_sln(int16_t *data, uint32_t samples, int16_t *other_data, uint32_t other_samples);
|
|
SWITCH_DECLARE(void) switch_mux_channels(int16_t *data, switch_size_t samples, uint32_t channels);
|
|
|
|
SWITCH_END_EXTERN_C
|
|
#endif
|
|
/* For Emacs:
|
|
* Local Variables:
|
|
* mode:c
|
|
* indent-tabs-mode:t
|
|
* tab-width:4
|
|
* c-basic-offset:4
|
|
* End:
|
|
* For VIM:
|
|
* vim:set softtabstop=4 shiftwidth=4 tabstop=4:
|
|
*/
|