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/**
* Copyright (c) 2019-2021 Chris Hiszpanski. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
* SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
* OF SUCH DAMAGE.
*/
#ifndef URTC_G711_H
#define URTC_G711_H
#ifdef __cplusplus
extern "C" {
#endif
#include <stddef.h>
#include <stdint.h>
extern const uint8_t pcm2ulaw[];
extern const int16_t ulaw2pcm[];
/**
* ITU-T G.711 compand a 16-bit signed PCM audio buffer. Buffer may contain
* multiple channels, in which case \a n must be the number of frames times
* the number of channels.
*
* Only the upper 13-bits are companded. The lowest 3-bits are discarded.
*
* \a dst must be allocated and point to at least (\a n / 2) bytes. \a dst
* and \a src may overlap.
*
* @param dst Destination buffer
* @param src Signed 16-bit sample source buffer
* @param n Number of samples (frames times channels)
*/
void g711_encode(uint8_t *dst, const int16_t *src, size_t n);
/**
* ITU-T G.711 decompand to a 16-bit signed PCM audio buffer. Buffer may
* contain multiple channels, in which case \a n must be the number of frames
* times the number of channels.
*
* The decompanded samples are normalized to 16-bits (the lowest 3-bits will be
* zero).
*
* \a dst must NOT overlap with \a src.
*
* @param dst Destination buffer
* @param src Signed 16-bit sample source buffer
* @param n Number of samples (frames times channels)
*/
void g711_decode(int16_t *dst, const uint8_t *src, size_t n);
#ifdef __cplusplus
}
#endif
#endif /* URTC_G711_H */
/* vim: set expandtab ts=8 sw=4 tw=0 : */
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