14f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber/* ------------------------------------------------------------------ 24f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * Copyright (C) 1998-2009 PacketVideo 34f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * 44f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * Licensed under the Apache License, Version 2.0 (the "License"); 54f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * you may not use this file except in compliance with the License. 64f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * You may obtain a copy of the License at 74f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * 84f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * http://www.apache.org/licenses/LICENSE-2.0 94f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * 104f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * Unless required by applicable law or agreed to in writing, software 114f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * distributed under the License is distributed on an "AS IS" BASIS, 124f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either 134f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * express or implied. 144f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * See the License for the specific language governing permissions 154f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * and limitations under the License. 164f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * ------------------------------------------------------------------- 174f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber */ 184f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber/**************************************************************************************** 194f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas HuberPortions of this file are derived from the following 3GPP standard: 204f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 214f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 3GPP TS 26.073 224f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber ANSI-C code for the Adaptive Multi-Rate (AMR) speech codec 234f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Available from http://www.3gpp.org 244f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 254f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber(C) 2004, 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TTA, TTC) 264f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas HuberPermission to distribute, modify and use this file under the standard license 274f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huberterms listed above has been obtained from the copyright holder. 284f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber****************************************************************************************/ 294f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber/* 304f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 314f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Pathname: ./audio/gsm-amr/c/src/az_lsp.c 324f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Funtions: Chebps 334f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Chebps_Wrapper 344f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Az_lsp 354f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 364f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber------------------------------------------------------------------------------ 374f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber REVISION HISTORY 384f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 394f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Description: Finished first pass of optimization. 404f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 414f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Description: Made changes based on review comments. 424f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 434f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Description: Made input to Chebps_Wrapper consistent with that of Chebps. 444f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 454f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Description: Replaced current Pseudo-code with the UMTS code version 3.2.0. 464f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Updated coding template. 474f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 484f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Description: Replaced basic_op.h and oper_32b.h with the header files of the 494f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber math functions used by the file. 504f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 514f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Description: Made the following changes per comments from Phase 2/3 review: 524f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1. Used "-" operator instead of calling sub function in the 534f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber az_lsp() code. 544f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 2. Copied detailed function description of az_lsp from the 554f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber header file. 564f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 3. Modified local variable definition to one per line. 574f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 4. Used NC in the definition of f1 and f2 arrays. 584f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 5. Added curly brackets in the IF statement. 594f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 604f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Description: Changed function interface to pass in a pointer to overflow 614f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber flag into the function instead of using a global flag. Removed 624f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber inclusion of unneeded header files. 634f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 644f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Description: For Chebps() and Az_lsp() 654f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1. Eliminated unused include files. 664f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 2. Replaced array addressing by pointers 674f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 3. Eliminated math operations that unnecessary checked for 684f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber saturation. 694f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 4. Eliminated not needed variables 704f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 5. Eliminated if-else checks for saturation 714f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 6. Deleted unused function cheps_wraper 724f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 734f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Description: Added casting to eliminate warnings 744f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 754f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 764f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Who: Date: 774f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Description: 784f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 794f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber------------------------------------------------------------------------------ 804f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber MODULE DESCRIPTION 814f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 824f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber These modules compute the LSPs from the LP coefficients. 834f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 844f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber------------------------------------------------------------------------------ 854f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber*/ 864f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 874f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 884f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber/*---------------------------------------------------------------------------- 894f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber; INCLUDES 904f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber----------------------------------------------------------------------------*/ 914f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber#include "az_lsp.h" 924f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber#include "cnst.h" 934f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber#include "basic_op.h" 944f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 954f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber/*---------------------------------------------------------------------------- 964f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber; MACROS 974f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber; Define module specific macros here 984f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber----------------------------------------------------------------------------*/ 994f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1004f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1014f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber/*---------------------------------------------------------------------------- 1024f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber; DEFINES 1034f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber; Include all pre-processor statements here. Include conditional 1044f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber; compile variables also. 1054f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber----------------------------------------------------------------------------*/ 1064f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber#define NC M/2 /* M = LPC order, NC = M/2 */ 1074f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1084f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber/*---------------------------------------------------------------------------- 1094f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber; LOCAL FUNCTION DEFINITIONS 1104f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber; Function Prototype declaration 1114f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber----------------------------------------------------------------------------*/ 1124f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1134f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1144f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber/*---------------------------------------------------------------------------- 1154f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber; LOCAL VARIABLE DEFINITIONS 1164f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber; Variable declaration - defined here and used outside this module 1174f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber----------------------------------------------------------------------------*/ 1184f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1194f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber/* 1204f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber------------------------------------------------------------------------------ 1214f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber FUNCTION NAME: Chebps 1224f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber------------------------------------------------------------------------------ 1234f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber INPUT AND OUTPUT DEFINITIONS 1244f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1254f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Inputs: 1264f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber x = input value (Word16) 1274f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber f = polynomial (Word16) 1284f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber n = polynomial order (Word16) 1294f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1304f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber pOverflow = pointer to overflow (Flag) 1314f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1324f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Outputs: 1334f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber pOverflow -> 1 if the operations in the function resulted in saturation. 1344f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1354f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Returns: 1364f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber cheb = Chebyshev polynomial for the input value x.(Word16) 1374f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1384f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Global Variables Used: 1394f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber None. 1404f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1414f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Local Variables Needed: 1424f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber None. 1434f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1444f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber------------------------------------------------------------------------------ 1454f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber FUNCTION DESCRIPTION 1464f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1474f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber This module evaluates the Chebyshev polynomial series. 1484f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber - The polynomial order is n = m/2 = 5 1494f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber - The polynomial F(z) (F1(z) or F2(z)) is given by 1504f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber F(w) = 2 exp(-j5w) C(x) 1514f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber where 1524f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber C(x) = T_n(x) + f(1)T_n-1(x) + ... +f(n-1)T_1(x) + f(n)/2 1534f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber and T_m(x) = cos(mw) is the mth order Chebyshev 1544f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber polynomial ( x=cos(w) ) 1554f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber - C(x) for the input x is returned. 1564f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1574f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber------------------------------------------------------------------------------ 1584f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber REQUIREMENTS 1594f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1604f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber None. 1614f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1624f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber------------------------------------------------------------------------------ 1634f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber REFERENCES 1644f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1654f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber az_lsp.c, UMTS GSM AMR speech codec, R99 - Version 3.2.0, March 2, 2001 1664f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1674f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber------------------------------------------------------------------------------ 1684f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber PSEUDO-CODE 1694f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1704f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huberstatic Word16 Chebps (Word16 x, 1714f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 f[], // (n) 1724f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 n) 1734f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber{ 1744f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 i, cheb; 1754f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 b0_h, b0_l, b1_h, b1_l, b2_h, b2_l; 1764f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word32 t0; 1774f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1784f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber// The reference ETSI code uses a global flag for Overflow. However, in the 1794f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber// actual implementation a pointer to Overflow flag is passed in as a 1804f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber// parameter to the function. This pointer is passed into all the basic math 1814f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber// functions invoked 1824f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1834f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber b2_h = 256; // b2 = 1.0 1844f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber b2_l = 0; 1854f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1864f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber t0 = L_mult (x, 512); // 2*x 1874f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber t0 = L_mac (t0, f[1], 8192); // + f[1] 1884f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber L_Extract (t0, &b1_h, &b1_l); // b1 = 2*x + f[1] 1894f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1904f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber for (i = 2; i < n; i++) 1914f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber { 1924f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber t0 = Mpy_32_16 (b1_h, b1_l, x); // t0 = 2.0*x*b1 1934f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber t0 = L_shl (t0, 1); 1944f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber t0 = L_mac (t0, b2_h, (Word16) 0x8000); // t0 = 2.0*x*b1 - b2 1954f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber t0 = L_msu (t0, b2_l, 1); 1964f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber t0 = L_mac (t0, f[i], 8192); // t0 = 2.0*x*b1 - b2 + f[i] 1974f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1984f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber L_Extract (t0, &b0_h, &b0_l); // b0 = 2.0*x*b1 - b2 + f[i] 1994f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 2004f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber b2_l = b1_l; // b2 = b1; 2014f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber b2_h = b1_h; 2024f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber b1_l = b0_l; // b1 = b0; 2034f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber b1_h = b0_h; 2044f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber } 2054f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 2064f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber t0 = Mpy_32_16 (b1_h, b1_l, x); // t0 = x*b1; 2074f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber t0 = L_mac (t0, b2_h, (Word16) 0x8000); // t0 = x*b1 - b2 2084f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber t0 = L_msu (t0, b2_l, 1); 2094f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber t0 = L_mac (t0, f[i], 4096); // t0 = x*b1 - b2 + f[i]/2 2104f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 2114f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber t0 = L_shl (t0, 6); 2124f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 2134f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber cheb = extract_h (t0); 2144f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 2154f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber return (cheb); 2164f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber} 2174f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 2184f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber------------------------------------------------------------------------------ 2194f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber RESOURCES USED [optional] 2204f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 2214f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber When the code is written for a specific target processor the 2224f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber the resources used should be documented below. 2234f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 2244f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber HEAP MEMORY USED: x bytes 2254f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 2264f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber STACK MEMORY USED: x bytes 2274f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 2284f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber CLOCK CYCLES: (cycle count equation for this function) + (variable 2294f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber used to represent cycle count for each subroutine 2304f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber called) 2314f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber where: (cycle count variable) = cycle count for [subroutine 2324f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber name] 2334f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 2344f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber------------------------------------------------------------------------------ 2354f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber CAUTION [optional] 2364f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber [State any special notes, constraints or cautions for users of this function] 2374f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 2384f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber------------------------------------------------------------------------------ 2394f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber*/ 240b875f69d8e867cb64bd101e66d85a880537c2b72Dan Austin#ifdef __clang__ 241b875f69d8e867cb64bd101e66d85a880537c2b72Dan Austin__attribute__((no_sanitize("integer"))) 242b875f69d8e867cb64bd101e66d85a880537c2b72Dan Austin#endif 2434f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huberstatic Word16 Chebps(Word16 x, 2444f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 f[], /* (n) */ 2454f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 n, 2464f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Flag *pOverflow) 2474f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber{ 2484f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 i; 2494f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 cheb; 2504f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 b1_h; 2514f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 b1_l; 2524f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word32 t0; 2534f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word32 L_temp; 2544f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 *p_f = &f[1]; 2554f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 2564f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber OSCL_UNUSED_ARG(pOverflow); 2574f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 2584f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber /* L_temp = 1.0 */ 2594f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 2604f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber L_temp = 0x01000000L; 2614f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 2624f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber t0 = ((Word32) x << 10) + ((Word32) * (p_f++) << 14); 2634f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 2644f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber /* b1 = t0 = 2*x + f[1] */ 2654f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 2664f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber b1_h = (Word16)(t0 >> 16); 2674f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber b1_l = (Word16)((t0 >> 1) - (b1_h << 15)); 2684f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 2694f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 2704f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber for (i = 2; i < n; i++) 2714f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber { 2724f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber /* t0 = 2.0*x*b1 */ 2734f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber t0 = ((Word32) b1_h * x); 2744f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber t0 += ((Word32) b1_l * x) >> 15; 2754f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber t0 <<= 2; 2764f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 2774f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber /* t0 = 2.0*x*b1 - b2 */ 2784f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber t0 -= L_temp; 2794f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 2804f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber /* t0 = 2.0*x*b1 - b2 + f[i] */ 2814f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber t0 += (Word32) * (p_f++) << 14; 2824f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 2834f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber L_temp = ((Word32) b1_h << 16) + ((Word32) b1_l << 1); 2844f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 2854f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber /* b0 = 2.0*x*b1 - b2 + f[i]*/ 2864f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber b1_h = (Word16)(t0 >> 16); 2874f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber b1_l = (Word16)((t0 >> 1) - (b1_h << 15)); 2884f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 2894f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber } 2904f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 2914f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber /* t0 = x*b1; */ 2924f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber t0 = ((Word32) b1_h * x); 2934f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber t0 += ((Word32) b1_l * x) >> 15; 2944f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber t0 <<= 1; 2954f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 2964f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 2974f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber /* t0 = x*b1 - b2 */ 2984f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber t0 -= L_temp; 2994f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 3004f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber /* t0 = x*b1 - b2 + f[i]/2 */ 3014f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber t0 += (Word32) * (p_f) << 13; 3024f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 3034f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 304773f457645786b139fa8fe180ef27e78ad7ab2f9Martin Storsjo if ((UWord32)(t0 - 0xfe000000L) < (UWord32)0x03ffffffL) 3054f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber { 3064f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber cheb = (Word16)(t0 >> 10); 3074f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber } 3084f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber else 3094f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber { 3104f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber if (t0 > (Word32) 0x01ffffffL) 3114f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber { 3124f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber cheb = MAX_16; 3134f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 3144f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber } 3154f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber else 3164f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber { 3174f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber cheb = MIN_16; 3184f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber } 3194f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber } 3204f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 3214f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber return (cheb); 3224f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber} 3234f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 3244f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 3254f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber/* 3264f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber------------------------------------------------------------------------------ 3274f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber FUNCTION NAME: Az_lsp 3284f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber------------------------------------------------------------------------------ 3294f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber INPUT AND OUTPUT DEFINITIONS FOR Az_lsp 3304f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 3314f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Inputs: 3324f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber a = predictor coefficients (Word16) 3334f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber lsp = line spectral pairs (Word16) 3344f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber old_lsp = old line spectral pairs (Word16) 3354f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 3364f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber pOverflow = pointer to overflow (Flag) 3374f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 3384f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Outputs: 3394f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber pOverflow -> 1 if the operations in the function resulted in saturation. 3404f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 3414f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Returns: 3424f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber None. 3434f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 3444f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Global Variables Used: 3454f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber None. 3464f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 3474f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Local Variables Needed: 3484f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber None. 3494f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 3504f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber------------------------------------------------------------------------------ 3514f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber FUNCTION DESCRIPTION 3524f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 3534f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber This function computes the LSPs from the LP coefficients. 3544f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 3554f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber The sum and difference filters are computed and divided by 1+z^{-1} and 3564f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1-z^{-1}, respectively. 3574f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 3584f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber f1[i] = a[i] + a[11-i] - f1[i-1] ; i=1,...,5 3594f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber f2[i] = a[i] - a[11-i] + f2[i-1] ; i=1,...,5 3604f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 3614f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber The roots of F1(z) and F2(z) are found using Chebyshev polynomial evaluation. 3624f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber The polynomials are evaluated at 60 points regularly spaced in the 3634f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber frequency domain. The sign change interval is subdivided 4 times to better 3644f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber track the root. The LSPs are found in the cosine domain [1,-1]. 3654f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 3664f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber If less than 10 roots are found, the LSPs from the past frame are used. 3674f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 3684f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber------------------------------------------------------------------------------ 3694f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber REQUIREMENTS 3704f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 3714f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber None. 3724f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 3734f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber------------------------------------------------------------------------------ 3744f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber REFERENCES 3754f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 3764f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber az_lsp.c, UMTS GSM AMR speech codec, R99 - Version 3.2.0, March 2, 2001 3774f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 3784f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber------------------------------------------------------------------------------ 3794f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber PSEUDO-CODE 3804f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 3814f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Hubervoid Az_lsp ( 3824f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 a[], // (i) : predictor coefficients (MP1) 3834f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 lsp[], // (o) : line spectral pairs (M) 3844f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 old_lsp[] // (i) : old lsp[] (in case not found 10 roots) (M) 3854f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber) 3864f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber{ 3874f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 i, j, nf, ip; 3884f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 xlow, ylow, xhigh, yhigh, xmid, ymid, xint; 3894f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 x, y, sign, exp; 3904f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 *coef; 3914f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 f1[M / 2 + 1], f2[M / 2 + 1]; 3924f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word32 t0; 3934f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 3944f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber *-------------------------------------------------------------* 3954f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * find the sum and diff. pol. F1(z) and F2(z) * 3964f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * F1(z) <--- F1(z)/(1+z**-1) & F2(z) <--- F2(z)/(1-z**-1) * 3974f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * * 3984f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * f1[0] = 1.0; * 3994f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * f2[0] = 1.0; * 4004f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * * 4014f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * for (i = 0; i< NC; i++) * 4024f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * { * 4034f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * f1[i+1] = a[i+1] + a[M-i] - f1[i] ; * 4044f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * f2[i+1] = a[i+1] - a[M-i] + f2[i] ; * 4054f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * } * 4064f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber *-------------------------------------------------------------* 4074f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 4084f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber f1[0] = 1024; // f1[0] = 1.0 4094f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber f2[0] = 1024; // f2[0] = 1.0 4104f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 4114f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber// The reference ETSI code uses a global flag for Overflow. However, in the 4124f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber// actual implementation a pointer to Overflow flag is passed in as a 4134f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber// parameter to the function. This pointer is passed into all the basic math 4144f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber// functions invoked 4154f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 4164f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber for (i = 0; i < NC; i++) 4174f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber { 4184f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber t0 = L_mult (a[i + 1], 8192); // x = (a[i+1] + a[M-i]) >> 2 4194f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber t0 = L_mac (t0, a[M - i], 8192); 4204f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber x = extract_h (t0); 4214f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber // f1[i+1] = a[i+1] + a[M-i] - f1[i] 4224f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber f1[i + 1] = sub (x, f1[i]); 4234f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 4244f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber t0 = L_mult (a[i + 1], 8192); // x = (a[i+1] - a[M-i]) >> 2 4254f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber t0 = L_msu (t0, a[M - i], 8192); 4264f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber x = extract_h (t0); 4274f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber // f2[i+1] = a[i+1] - a[M-i] + f2[i] 4284f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber f2[i + 1] = add (x, f2[i]); 4294f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber } 4304f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 4314f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber *-------------------------------------------------------------* 4324f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * find the LSPs using the Chebychev pol. evaluation * 4334f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber *-------------------------------------------------------------* 4344f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 4354f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber nf = 0; // number of found frequencies 4364f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber ip = 0; // indicator for f1 or f2 4374f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 4384f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber coef = f1; 4394f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 4404f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber xlow = grid[0]; 4414f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber ylow = Chebps (xlow, coef, NC); 4424f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 4434f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber j = 0; 4444f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber // while ( (nf < M) && (j < grid_points) ) 4454f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber while ((sub (nf, M) < 0) && (sub (j, grid_points) < 0)) 4464f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber { 4474f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber j++; 4484f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber xhigh = xlow; 4494f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber yhigh = ylow; 4504f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber xlow = grid[j]; 4514f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber ylow = Chebps (xlow, coef, NC); 4524f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 4534f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber if (L_mult (ylow, yhigh) <= (Word32) 0L) 4544f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber { 4554f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 4564f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber // divide 4 times the interval 4574f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 4584f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber for (i = 0; i < 4; i++) 4594f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber { 4604f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber // xmid = (xlow + xhigh)/2 4614f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber xmid = add (shr (xlow, 1), shr (xhigh, 1)); 4624f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber ymid = Chebps (xmid, coef, NC); 4634f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 4644f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber if (L_mult (ylow, ymid) <= (Word32) 0L) 4654f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber { 4664f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber yhigh = ymid; 4674f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber xhigh = xmid; 4684f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber } 4694f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber else 4704f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber { 4714f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber ylow = ymid; 4724f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber xlow = xmid; 4734f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber } 4744f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber } 4754f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 4764f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber *-------------------------------------------------------------* 4774f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * Linear interpolation * 4784f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * xint = xlow - ylow*(xhigh-xlow)/(yhigh-ylow); * 4794f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber *-------------------------------------------------------------* 4804f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 4814f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber x = sub (xhigh, xlow); 4824f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber y = sub (yhigh, ylow); 4834f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 4844f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber if (y == 0) 4854f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber { 4864f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber xint = xlow; 4874f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber } 4884f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber else 4894f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber { 4904f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber sign = y; 4914f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber y = abs_s (y); 4924f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber exp = norm_s (y); 4934f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber y = shl (y, exp); 4944f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber y = div_s ((Word16) 16383, y); 4954f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber t0 = L_mult (x, y); 4964f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber t0 = L_shr (t0, sub (20, exp)); 4974f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber y = extract_l (t0); // y= (xhigh-xlow)/(yhigh-ylow) 4984f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 4994f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber if (sign < 0) 5004f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber y = negate (y); 5014f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 5024f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber t0 = L_mult (ylow, y); 5034f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber t0 = L_shr (t0, 11); 5044f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber xint = sub (xlow, extract_l (t0)); // xint = xlow - ylow*y 5054f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber } 5064f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 5074f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber lsp[nf] = xint; 5084f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber xlow = xint; 5094f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber nf++; 5104f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 5114f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber if (ip == 0) 5124f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber { 5134f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber ip = 1; 5144f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber coef = f2; 5154f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber } 5164f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber else 5174f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber { 5184f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber ip = 0; 5194f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber coef = f1; 5204f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber } 5214f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber ylow = Chebps (xlow, coef, NC); 5224f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 5234f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber } 5244f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber } 5254f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 5264f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber // Check if M roots found 5274f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 5284f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber if (sub (nf, M) < 0) 5294f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber { 5304f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber for (i = 0; i < M; i++) 5314f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber { 5324f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber lsp[i] = old_lsp[i]; 5334f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber } 5344f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 5354f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber } 5364f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber return; 5374f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber} 5384f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 5394f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber------------------------------------------------------------------------------ 5404f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber RESOURCES USED [optional] 5414f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 5424f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber When the code is written for a specific target processor the 5434f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber the resources used should be documented below. 5444f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 5454f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber HEAP MEMORY USED: x bytes 5464f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 5474f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber STACK MEMORY USED: x bytes 5484f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 5494f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber CLOCK CYCLES: (cycle count equation for this function) + (variable 5504f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber used to represent cycle count for each subroutine 5514f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber called) 5524f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber where: (cycle count variable) = cycle count for [subroutine 5534f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber name] 5544f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 5554f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber------------------------------------------------------------------------------ 5564f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber CAUTION [optional] 5574f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber [State any special notes, constraints or cautions for users of this function] 5584f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 5594f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber------------------------------------------------------------------------------ 5604f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber*/ 5614f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 5624f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Hubervoid Az_lsp( 5634f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 a[], /* (i) : predictor coefficients (MP1) */ 5644f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 lsp[], /* (o) : line spectral pairs (M) */ 5654f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 old_lsp[], /* (i) : old lsp[] (in case not found 10 roots) (M) */ 5664f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Flag *pOverflow /* (i/o): overflow flag */ 5674f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber) 5684f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber{ 5692d0ac425564ff9882ebaac5267d1a04d4af67d00Bernhard Rosenkränzer Word16 i; 5702d0ac425564ff9882ebaac5267d1a04d4af67d00Bernhard Rosenkränzer Word16 j; 5712d0ac425564ff9882ebaac5267d1a04d4af67d00Bernhard Rosenkränzer Word16 nf; 5722d0ac425564ff9882ebaac5267d1a04d4af67d00Bernhard Rosenkränzer Word16 ip; 5734f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 xlow; 5744f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 ylow; 5754f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 xhigh; 5764f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 yhigh; 5774f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 xmid; 5784f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 ymid; 5794f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 xint; 5804f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 x; 5814f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 y; 5824f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 sign; 5834f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 exp; 5844f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 *coef; 5854f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 f1[NC + 1]; 5864f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 f2[NC + 1]; 5874f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word32 L_temp1; 5884f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word32 L_temp2; 5894f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 *p_f1 = f1; 5904f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 *p_f2 = f2; 5914f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 5924f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber /*-------------------------------------------------------------* 5934f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * find the sum and diff. pol. F1(z) and F2(z) * 5944f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * F1(z) <--- F1(z)/(1+z**-1) & F2(z) <--- F2(z)/(1-z**-1) * 5954f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * * 5964f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * f1[0] = 1.0; * 5974f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * f2[0] = 1.0; * 5984f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * * 5994f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * for (i = 0; i< NC; i++) * 6004f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * { * 6014f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * f1[i+1] = a[i+1] + a[M-i] - f1[i] ; * 6024f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * f2[i+1] = a[i+1] - a[M-i] + f2[i] ; * 6034f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * } * 6044f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber *-------------------------------------------------------------*/ 6054f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 6064f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber *p_f1 = 1024; /* f1[0] = 1.0 */ 6074f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber *p_f2 = 1024; /* f2[0] = 1.0 */ 6084f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 6094f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber for (i = 0; i < NC; i++) 6104f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber { 6114f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber L_temp1 = (Word32) * (a + i + 1); 6124f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber L_temp2 = (Word32) * (a + M - i); 6134f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber /* x = (a[i+1] + a[M-i]) >> 2 */ 6144f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber x = (Word16)((L_temp1 + L_temp2) >> 2); 6154f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber /* y = (a[i+1] - a[M-i]) >> 2 */ 6164f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber y = (Word16)((L_temp1 - L_temp2) >> 2); 6174f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber /* f1[i+1] = a[i+1] + a[M-i] - f1[i] */ 6184f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber x -= *(p_f1++); 6194f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber *(p_f1) = x; 6204f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber /* f2[i+1] = a[i+1] - a[M-i] + f2[i] */ 6214f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber y += *(p_f2++); 6224f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber *(p_f2) = y; 6234f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber } 6244f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 6254f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber /*-------------------------------------------------------------* 6264f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * find the LSPs using the Chebychev pol. evaluation * 6274f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber *-------------------------------------------------------------*/ 6284f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 6294f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber nf = 0; /* number of found frequencies */ 6304f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber ip = 0; /* indicator for f1 or f2 */ 6314f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 6324f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber coef = f1; 6334f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 6344f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber xlow = *(grid); 6354f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber ylow = Chebps(xlow, coef, NC, pOverflow); 6364f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 6374f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber j = 0; 6384f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 6394f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber while ((nf < M) && (j < grid_points)) 6404f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber { 6414f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber j++; 6424f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber xhigh = xlow; 6434f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber yhigh = ylow; 6444f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber xlow = *(grid + j); 6454f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber ylow = Chebps(xlow, coef, NC, pOverflow); 6464f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 6474f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber if (((Word32)ylow*yhigh) <= 0) 6484f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber { 6494f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber /* divide 4 times the interval */ 6504f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber for (i = 4; i != 0; i--) 6514f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber { 6524f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber /* xmid = (xlow + xhigh)/2 */ 6534f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber x = xlow >> 1; 6544f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber y = xhigh >> 1; 6554f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber xmid = x + y; 6564f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 6574f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber ymid = Chebps(xmid, coef, NC, pOverflow); 6584f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 6594f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber if (((Word32)ylow*ymid) <= 0) 6604f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber { 6614f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber yhigh = ymid; 6624f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber xhigh = xmid; 6634f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber } 6644f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber else 6654f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber { 6664f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber ylow = ymid; 6674f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber xlow = xmid; 6684f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber } 6694f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber } 6704f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 6714f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber /*-------------------------------------------------------------* 6724f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * Linear interpolation * 6734f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber * xint = xlow - ylow*(xhigh-xlow)/(yhigh-ylow); * 6744f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber *-------------------------------------------------------------*/ 6754f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 6764f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber x = xhigh - xlow; 6774f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber y = yhigh - ylow; 6784f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 6794f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber if (y == 0) 6804f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber { 6814f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber xint = xlow; 6824f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber } 6834f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber else 6844f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber { 6854f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber sign = y; 6864f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber y = abs_s(y); 6874f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber exp = norm_s(y); 6884f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber y <<= exp; 6894f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber y = div_s((Word16) 16383, y); 6904f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 6914f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber y = ((Word32)x * y) >> (19 - exp); 6924f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 6934f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber if (sign < 0) 6944f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber { 6954f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber y = -y; 6964f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber } 6974f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 6984f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber /* xint = xlow - ylow*y */ 6994f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber xint = xlow - (((Word32) ylow * y) >> 10); 7004f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber } 7014f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 7024f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber *(lsp + nf) = xint; 7034f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber xlow = xint; 7044f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber nf++; 7054f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 7064f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber if (ip == 0) 7074f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber { 7084f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber ip = 1; 7094f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber coef = f2; 7104f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber } 7114f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber else 7124f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber { 7134f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber ip = 0; 7144f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber coef = f1; 7154f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber } 7164f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 7174f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber ylow = Chebps(xlow, coef, NC, pOverflow); 7184f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 7194f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber } 7204f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber } 7214f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 7224f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber /* Check if M roots found */ 7234f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 7244f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber if (nf < M) 7254f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber { 7264f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber for (i = NC; i != 0 ; i--) 7274f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber { 7284f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber *lsp++ = *old_lsp++; 7294f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber *lsp++ = *old_lsp++; 7304f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber } 7314f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber } 7324f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 7334f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber} 7344f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 7354f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas HuberWord16 Chebps_Wrapper(Word16 x, 7364f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 f[], /* (n) */ 7374f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 n, 7384f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Flag *pOverflow) 7394f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber{ 7404f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber return Chebps(x, f, n, pOverflow); 7414f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber} 7424f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 743