auto import from //depot/cupcake/@135843

1 files changed, 0 insertions, 168 deletions

diff --git a/arm-wt-22k/lib_src/eas_math.c b/arm-wt-22k/lib_src/eas_math.c
deleted file mode 100644
index 12d788e..0000000
--- a/arm-wt-22k/lib_src/eas_math.c
+++ /dev/null
@@ -1,168 +0,0 @@
-/*----------------------------------------------------------------------------

- *

- * File: 

- * eas_math.c

- *

- * Contents and purpose:

- * Contains common math routines for the various audio engines.

- *

- *

- * 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: 586 $

- *   $Date: 2007-03-08 20:33:04 -0800 (Thu, 08 Mar 2007) $

- *----------------------------------------------------------------------------

-*/

-

-#include "eas.h"

-#include "eas_math.h"

-

-/* anything less than this converts to a fraction too small to represent in 32-bits */

-#define MIN_CENTS	-18000

-

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

- * EAS_Calculate2toX()

- *----------------------------------------------------------------------------

- * Purpose:

- * Calculate 2^x

- *

- * Inputs:

- * nCents - 	measured in cents

- * psEASData - pointer to overall EAS data structure

- *

- * Outputs:

- * nResult - int.frac result (where frac has NUM_DENTS_FRAC_BITS)

- *

- * Side Effects:

- *

- *----------------------------------------------------------------------------

-*/

-EAS_I32 EAS_Calculate2toX (EAS_I32 nCents)

-{

-	EAS_I32 nDents;

-	EAS_I32 nExponentInt, nExponentFrac;

-	EAS_I32 nTemp1, nTemp2;

-	EAS_I32 nResult;

-

-	/* check for minimum value */

-	if (nCents < MIN_CENTS)

-		return 0;

-

-	/* for the time being, convert cents to dents */

-	nDents = FMUL_15x15(nCents, CENTS_TO_DENTS);

-

-	nExponentInt = GET_DENTS_INT_PART(nDents);

-	nExponentFrac = GET_DENTS_FRAC_PART(nDents);

-

-	/*

-	implement 2^(fracPart) as a power series

-	*/

-	nTemp1 = GN2_TO_X2 + MULT_DENTS_COEF(nExponentFrac, GN2_TO_X3);

-	nTemp2 = GN2_TO_X1 + MULT_DENTS_COEF(nExponentFrac, nTemp1);

-	nTemp1 = GN2_TO_X0 + MULT_DENTS_COEF(nExponentFrac, nTemp2);

-

-	/*

-	implement 2^(intPart) as 

-	a left shift for intPart >= 0 or

-	a left shift for intPart <  0

-	*/

-	if (nExponentInt >= 0)

-	{

-		/* left shift for positive exponents */

-		/*lint -e{703} <avoid multiply for performance>*/

-		nResult = nTemp1 << nExponentInt;

-	}

-	else

-	{

-		/* right shift for negative exponents */

-		nExponentInt = -nExponentInt;

-		nResult = nTemp1 >> nExponentInt;

-	}

-

-	return nResult;

-}

-

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

- * EAS_LogToLinear16()

- *----------------------------------------------------------------------------

- * Purpose:

- * Transform log value to linear gain multiplier using piece-wise linear

- * approximation

- *

- * Inputs:

- * nGain - log scale value in 20.10 format. Even though gain is normally

- * stored in 6.10 (16-bit) format we use 32-bit numbers here to eliminate

- * the need for saturation checking when combining gain values.

- *

- * Outputs:

- * Returns a 16-bit linear value approximately equal to 2^(nGain/1024)

- *

- * Side Effects:

- *

- *----------------------------------------------------------------------------

-*/

-EAS_U16 EAS_LogToLinear16 (EAS_I32 nGain)

-{

-	EAS_INT nExp;

-	EAS_U16 nTemp;

-

-	/* bias to positive */

-	nGain += 32767;

-

-	/* check for infinite attenuation */

-	if (nGain < 0)

-		return 0;

-

-	/* extract the exponent */

-	nExp = 31 - (nGain >> 10);

-

-	/* check for maximum output */

-	if (nExp < 0)

-		return 0x7fff;

-

-	/* extract mantissa and restore implied 1 bit */

-	nTemp = (EAS_U16)((((nGain & 0x3ff) << 4) | 0x4000) >> nExp);

-

-	/* use shift to approximate power-of-2 operation */

-	return nTemp;

-}

-

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

- * EAS_VolumeToGain()

- *----------------------------------------------------------------------------

- * Purpose:

- * Transform volume control in 1dB increments to gain multiplier

- *

- * Inputs:

- * volume - 100 = 0dB, 99 = -1dB, 0 = -inf

- *

- * Outputs:

- * Returns a 16-bit linear value 

- *----------------------------------------------------------------------------

-*/

-EAS_I16 EAS_VolumeToGain (EAS_INT volume)

-{

-	/* check for limits */

-	if (volume <= 0)

-		return 0;

-	if (volume >= 100)

-		return 0x7fff;

-	

-	/*lint -e{702} use shift instead of division */

-	return (EAS_I16) EAS_Calculate2toX((((volume - EAS_MAX_VOLUME) * 204099) >> 10) - 1);

-}

-