198913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project/* Copyright (C) 2002 Jean-Marc Valin */ 298913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project/** 398913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project @file lpc.h 498913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project @brief Functions for LPC (Linear Prediction Coefficients) analysis 598913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project*/ 698913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project/* 798913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project Redistribution and use in source and binary forms, with or without 898913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project modification, are permitted provided that the following conditions 998913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project are met: 1098913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project 1198913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project - Redistributions of source code must retain the above copyright 1298913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project notice, this list of conditions and the following disclaimer. 1398913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project 1498913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project - Redistributions in binary form must reproduce the above copyright 1598913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project notice, this list of conditions and the following disclaimer in the 1698913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project documentation and/or other materials provided with the distribution. 1798913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project 1898913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project - Neither the name of the Xiph.org Foundation nor the names of its 1998913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project contributors may be used to endorse or promote products derived from 2098913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project this software without specific prior written permission. 2198913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project 2298913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 2398913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 2498913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 2598913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR 2698913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 2798913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 2898913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 2998913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 3098913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 3198913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 3298913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 3398913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project*/ 3498913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project 3598913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project#ifndef LPC_H 3698913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project#define LPC_H 3798913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project 3898913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project#include "arch.h" 3998913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project 4098913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Projectvoid _spx_autocorr( 4198913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project const spx_word16_t * x, /* in: [0...n-1] samples x */ 4298913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project spx_word16_t *ac, /* out: [0...lag-1] ac values */ 4398913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project int lag, int n); 4498913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project 4598913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Projectspx_word32_t /* returns minimum mean square error */ 4698913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project_spx_lpc( 4798913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project spx_coef_t * lpc, /* [0...p-1] LPC coefficients */ 4898913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project const spx_word16_t * ac, /* in: [0...p] autocorrelation values */ 4998913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project int p 5098913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project ); 5198913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project 5298913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project 5398913fed6520d8849fb2e246be943e04474aefaThe Android Open Source Project#endif 54