You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
51 lines
2.1 KiB
51 lines
2.1 KiB
14 years ago
|
/* Copyright (C) 2002 Jean-Marc Valin
|
||
|
|
File: lpc.h
|
||
|
|
Functions for LPC (Linear Prediction Coefficients) analysis
|
||
|
|
|
||
|
|
Redistribution and use in source and binary forms, with or without
|
||
|
|
modification, are permitted provided that the following conditions
|
||
|
|
are met:
|
||
|
|
|
||
|
|
- Redistributions of source code must retain the above copyright
|
||
|
|
notice, this list of conditions and the following disclaimer.
|
||
|
|
|
||
|
|
- 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.
|
||
|
|
|
||
|
|
- Neither the name of the Xiph.org Foundation nor the names of its
|
||
|
|
contributors may be used to endorse or promote products derived from
|
||
|
|
this software without specific prior written permission.
|
||
|
|
|
||
|
|
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
||
|
|
``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 FOUNDATION OR
|
||
|
|
CONTRIBUTORS 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 LPC_H
|
||
|
|
#define LPC_H
|
||
|
|
|
||
|
|
void _spx_autocorr(
|
||
|
|
const float * x, /* in: [0...n-1] samples x */
|
||
|
|
float *ac, /* out: [0...lag-1] ac values */
|
||
|
|
int lag, int n);
|
||
|
|
|
||
|
|
float /* returns minimum mean square error */
|
||
|
|
wld(
|
||
|
|
float * lpc, /* [0...p-1] LPC coefficients */
|
||
|
|
const float * ac, /* in: [0...p] autocorrelation values */
|
||
|
|
float * ref, /* out: [0...p-1] reflection coef's */
|
||
|
|
int p
|
||
|
|
);
|
||
|
|
|
||
|
|
|
||
|
|
#endif
|