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 Filename: /audio/gsm_amr/c/src/pow2.c 324f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 334f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber------------------------------------------------------------------------------ 344f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber REVISION HISTORY 354f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 364f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Description: Updated template. Changed function interface to pass in a 374f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber pointer to overflow flag into the function instead of using a 384f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber global flag. Removed inclusion of "pow2.tab" 394f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 404f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Who: Date: 414f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Description: 424f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 434f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber------------------------------------------------------------------------------ 444f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber*/ 454f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 464f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber/*---------------------------------------------------------------------------- 474f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber; INCLUDES 484f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber----------------------------------------------------------------------------*/ 494f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber#include "pow2.h" 504f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber#include "basic_op.h" 514f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 524f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber/*---------------------------------------------------------------------------- 534f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber; MACROS 544f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber; Define module specific macros here 554f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber----------------------------------------------------------------------------*/ 564f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 574f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 584f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber/*---------------------------------------------------------------------------- 594f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber; DEFINES 604f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber; Include all pre-processor statements here. Include conditional 614f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber; compile variables also. 624f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber----------------------------------------------------------------------------*/ 634f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 644f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber/*---------------------------------------------------------------------------- 654f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber; LOCAL FUNCTION DEFINITIONS 664f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber; Function Prototype declaration 674f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber----------------------------------------------------------------------------*/ 684f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 694f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber/*---------------------------------------------------------------------------- 704f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber; LOCAL STORE/BUFFER/POINTER DEFINITIONS 714f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber; Variable declaration - defined here and used outside this module 724f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber----------------------------------------------------------------------------*/ 734f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 744f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 754f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber/* 764f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber------------------------------------------------------------------------------ 774f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber FUNCTION NAME: Pow2 784f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber------------------------------------------------------------------------------ 794f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber INPUT AND OUTPUT DEFINITIONS 804f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 814f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Inputs: 824f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber exponent = Integer part whose valid range is: 0 <= value <= 30 (Word16) 834f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber fraction = Fractional part whose valid range is 0 <= value < 1 844f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 854f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber pOverflow = pointer to overflow flag 864f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 874f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Outputs: 884f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber L_x = Result of the Pow2() computation (Word32) 894f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber pOverflow -> 1 if the Pow2() function results in saturation 904f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 914f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Returns: 924f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber None 934f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 944f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Global Variables Used: 954f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber None 964f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 974f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Local Variables Needed: 984f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber None 994f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1004f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber------------------------------------------------------------------------------ 1014f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber FUNCTION DESCRIPTION 1024f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1034f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber This function computes L_x = pow(2.0, exponent.fraction) 1044f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1054f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber The function Pow2(L_x) is approximated by a table and linear interpolation. 1064f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1074f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1- i = bit10-b15 of fraction, 0 <= i <= 31 1084f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 2- a = bit0-b9 of fraction 1094f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 3- L_x = table[i]<<16 - (table[i] - table[i+1]) * a * 2 1104f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 4- L_x = L_x >> (30-exponent) (with rounding) 1114f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1124f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber------------------------------------------------------------------------------ 1134f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber REQUIREMENTS 1144f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1154f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber None 1164f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1174f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber------------------------------------------------------------------------------ 1184f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber REFERENCES 1194f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1204f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber pow2.c, UMTS GSM AMR speech codec, R99 - Version 3.2.0, March 2, 2001 1214f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1224f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber------------------------------------------------------------------------------ 1234f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber PSEUDO-CODE 1244f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1254f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas HuberWord32 Pow2 ( // (o) : result (range: 0<=val<=0x7fffffff) 1264f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 exponent, // (i) : Integer part. (range: 0<=val<=30) 1274f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 fraction // (i) : Fractional part. (range: 0.0<=val<1.0) 1284f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber) 1294f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber{ 1304f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 exp, i, a, tmp; 1314f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word32 L_x; 1324f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1334f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber L_x = L_mult (fraction, 32); // L_x = fraction<<6 1344f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber i = extract_h (L_x); // Extract b10-b16 of fraction 1354f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber L_x = L_shr (L_x, 1); 1364f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber a = extract_l (L_x); // Extract b0-b9 of fraction 1374f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber a = a & (Word16) 0x7fff; 1384f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1394f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber L_x = L_deposit_h (table[i]); // table[i] << 16 1404f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber tmp = sub (table[i], table[i + 1]); // table[i] - table[i+1] 1414f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber L_x = L_msu (L_x, tmp, a); // L_x -= tmp*a*2 1424f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1434f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber exp = sub (30, exponent); 1444f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber L_x = L_shr_r (L_x, exp); 1454f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1464f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber return (L_x); 1474f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber} 1484f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1494f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber------------------------------------------------------------------------------ 1504f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber RESOURCES USED [optional] 1514f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1524f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber When the code is written for a specific target processor the 1534f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber the resources used should be documented below. 1544f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1554f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber HEAP MEMORY USED: x bytes 1564f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1574f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber STACK MEMORY USED: x bytes 1584f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1594f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber CLOCK CYCLES: (cycle count equation for this function) + (variable 1604f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber used to represent cycle count for each subroutine 1614f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber called) 1624f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber where: (cycle count variable) = cycle count for [subroutine 1634f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber name] 1644f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1654f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber------------------------------------------------------------------------------ 1664f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber CAUTION [optional] 1674f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber [State any special notes, constraints or cautions for users of this function] 1684f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1694f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber------------------------------------------------------------------------------ 1704f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber*/ 1714f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1724f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber/*---------------------------------------------------------------------------- 1734f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber; FUNCTION CODE 1744f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber----------------------------------------------------------------------------*/ 1754f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1764f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas HuberWord32 Pow2( /* (o) : result (range: 0<=val<=0x7fffffff) */ 1774f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 exponent, /* (i) : Integer part. (range: 0<=val<=30) */ 1784f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 fraction, /* (i) : Fractional part. (range: 0.0<=val<1.0) */ 1794f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Flag *pOverflow 1804f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber) 1814f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber{ 1824f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word16 exp, i, a, tmp; 1834f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber Word32 L_x; 1844f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1854f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber L_x = L_mult(fraction, 32, pOverflow); /* L_x = fraction<<6 */ 1864f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1874f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber /* Extract b0-b16 of fraction */ 1884f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1894f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber i = ((Word16)(L_x >> 16)) & 31; /* ensure index i is bounded */ 1904f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber a = (Word16)((L_x >> 1) & 0x7fff); 1914f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1924f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber L_x = L_deposit_h(pow2_tbl[i]); /* pow2_tbl[i] << 16 */ 1934f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1944f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber /* pow2_tbl[i] - pow2_tbl[i+1] */ 1954f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber tmp = sub(pow2_tbl[i], pow2_tbl[i + 1], pOverflow); 1964f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber L_x = L_msu(L_x, tmp, a, pOverflow); /* L_x -= tmp*a*2 */ 1974f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 1984f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber exp = sub(30, exponent, pOverflow); 1994f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber L_x = L_shr_r(L_x, exp, pOverflow); 2004f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber 2014f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber return (L_x); 2024f1efc098cb5791c3e9f483f2af84aef70d2d0a0Andreas Huber} 203