156c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks/*---------------------------------------------------------------------------- 256c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks * 356c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks * File: 456c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks * eas_pan.c 556c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks * 656c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks * Contents and purpose: 756c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks * Calculates left and right gain multipliers based on a pan value from -63 to +63 856c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks * 956c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks * NOTES: 1056c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks * The _CMX_PARSER and _MFI_PARSER preprocessor symbols determine 1156c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks * whether the parser works for those particular file formats. 1256c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks * 1356c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks * Copyright Sonic Network Inc. 2005 147df30109963092559d3760c0661a020f9daf1030The Android Open Source Project 157df30109963092559d3760c0661a020f9daf1030The Android Open Source Project * Licensed under the Apache License, Version 2.0 (the "License"); 167df30109963092559d3760c0661a020f9daf1030The Android Open Source Project * you may not use this file except in compliance with the License. 177df30109963092559d3760c0661a020f9daf1030The Android Open Source Project * You may obtain a copy of the License at 187df30109963092559d3760c0661a020f9daf1030The Android Open Source Project * 197df30109963092559d3760c0661a020f9daf1030The Android Open Source Project * http://www.apache.org/licenses/LICENSE-2.0 207df30109963092559d3760c0661a020f9daf1030The Android Open Source Project * 217df30109963092559d3760c0661a020f9daf1030The Android Open Source Project * Unless required by applicable law or agreed to in writing, software 227df30109963092559d3760c0661a020f9daf1030The Android Open Source Project * distributed under the License is distributed on an "AS IS" BASIS, 237df30109963092559d3760c0661a020f9daf1030The Android Open Source Project * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 247df30109963092559d3760c0661a020f9daf1030The Android Open Source Project * See the License for the specific language governing permissions and 257df30109963092559d3760c0661a020f9daf1030The Android Open Source Project * limitations under the License. 2656c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks * 2756c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks *---------------------------------------------------------------------------- 2856c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks * Revision Control: 2956c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks * $Revision: 82 $ 3056c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks * $Date: 2006-07-10 11:45:19 -0700 (Mon, 10 Jul 2006) $ 3156c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks *---------------------------------------------------------------------------- 3256c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks*/ 3356c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks 3456c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks#include "eas_pan.h" 3556c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks#include "eas_math.h" 3656c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks 3756c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks/*---------------------------------------------------------------------------- 3856c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks * EAS_CalcPanControl() 3956c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks *---------------------------------------------------------------------------- 4056c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks * Purpose: 4156c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks * Assign the left and right gain values corresponding to the given pan value. 4256c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks * 4356c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks * This routine uses sin/cos approximations for an equal power curve: 4456c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks * 4556c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks * sin(x) = (2-4*c)*x^2 + c + x 4656c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks * cos(x) = (2-4*c)*x^2 + c - x 4756c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks * 4856c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks * where c = 1/sqrt(2) 4956c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks * using the a0 + x*(a1 + x*a2) approach 5056c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks * 5156c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks * Inputs: 5256c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks * pan - pan value (-63 to + 63) 5356c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks * 5456c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks * Outputs: 5556c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks * pGainLeft linear gain multiplier for left channel (15-bit fraction) 5656c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks * pGainRight linear gain multiplier for left channel (15-bit fraction) 5756c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks * 5856c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks * Side Effects: 5956c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks *---------------------------------------------------------------------------- 6056c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks*/ 6156c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparksvoid EAS_CalcPanControl (EAS_INT pan, EAS_I16 *pGainLeft, EAS_I16 *pGainRight) 6256c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks{ 6356c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks EAS_INT temp; 6456c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks EAS_INT netAngle; 6556c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks 6656c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks /* impose hard limit */ 6756c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks if (pan < -63) 6856c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks netAngle = -63; 6956c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks else if (pan > 63) 7056c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks netAngle = 63; 7156c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks else 7256c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks netAngle = pan; 7356c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks 7456c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks /*lint -e{701} <avoid multiply for performance reasons>*/ 7556c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks netAngle = netAngle << 8; 7656c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks 7756c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks /* calculate sin */ 7856c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks temp = EG1_ONE + FMUL_15x15(COEFF_PAN_G2, netAngle); 7956c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks temp = COEFF_PAN_G0 + FMUL_15x15(temp, netAngle); 8056c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks 8156c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks if (temp > SYNTH_FULL_SCALE_EG1_GAIN) 8256c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks temp = SYNTH_FULL_SCALE_EG1_GAIN; 8356c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks else if (temp < 0) 8456c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks temp = 0; 8556c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks 8656c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks *pGainRight = (EAS_I16) temp; 8756c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks 8856c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks /* calculate cos */ 8956c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks temp = -EG1_ONE + FMUL_15x15(COEFF_PAN_G2, netAngle); 9056c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks temp = COEFF_PAN_G0 + FMUL_15x15(temp, netAngle); 9156c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks if (temp > SYNTH_FULL_SCALE_EG1_GAIN) 9256c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks temp = SYNTH_FULL_SCALE_EG1_GAIN; 9356c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks else if (temp < 0) 9456c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks temp = 0; 9556c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks 9656c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks *pGainLeft = (EAS_I16) temp; 9756c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks} 9856c99cd2c2c1e6ab038dac5fced5b92ccf11ff6cDave Sparks 99