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/*----------------------------------------------------------------------------
*
* 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