| /*---------------------------------------------------------------------------- |
| * |
| * File: |
| * eas_pan.h |
| * |
| * Contents and purpose: |
| * Calculates left and right gain multipliers based on a pan value from -63 to +63 |
| * |
| * NOTES: |
| * The _CMX_PARSER and _MFI_PARSER preprocessor symbols determine |
| * whether the parser works for those particular file formats. |
| * |
| * Copyright Sonic Network Inc. 2005 |
| |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| * |
| *---------------------------------------------------------------------------- |
| * Revision Control: |
| * $Revision: 82 $ |
| * $Date: 2006-07-10 11:45:19 -0700 (Mon, 10 Jul 2006) $ |
| *---------------------------------------------------------------------------- |
| */ |
| |
| #ifndef EAS_PAN_H |
| #define _EAS_PAN_H |
| |
| #include "eas_types.h" |
| |
| /*---------------------------------------------------------------------------- |
| * EAS_CalcPanControl() |
| *---------------------------------------------------------------------------- |
| * Purpose: |
| * Assign the left and right gain values corresponding to the given pan value. |
| * |
| * This routine uses sin/cos approximations for an equal power curve: |
| * |
| * sin(x) = (2-4*c)*x^2 + c + x |
| * cos(x) = (2-4*c)*x^2 + c - x |
| * |
| * where c = 1/sqrt(2) |
| * using the a0 + x*(a1 + x*a2) approach |
| * |
| * Inputs: |
| * pan - pan value (-63 to + 63) |
| * |
| * Outputs: |
| * pGainLeft linear gain multiplier for left channel (15-bit fraction) |
| * pGainRight linear gain multiplier for left channel (15-bit fraction) |
| * |
| * Side Effects: |
| *---------------------------------------------------------------------------- |
| */ |
| void EAS_CalcPanControl (EAS_INT pan, EAS_I16 *pGainLeft, EAS_I16 *pGainRight); |
| |
| #endif |
| |
