libFDK/src/scale.cpp

/* -----------------------------------------------------------------------------------------------------------
Software License for The Fraunhofer FDK AAC Codec Library for Android

 Copyright  1995 - 2012 Fraunhofer-Gesellschaft zur Frderung der angewandten Forschung e.V.
  All rights reserved.

 1.    INTRODUCTION
The Fraunhofer FDK AAC Codec Library for Android ("FDK AAC Codec") is software that implements
the MPEG Advanced Audio Coding ("AAC") encoding and decoding scheme for digital audio.
This FDK AAC Codec software is intended to be used on a wide variety of Android devices.

AAC's HE-AAC and HE-AAC v2 versions are regarded as today's most efficient general perceptual
audio codecs. AAC-ELD is considered the best-performing full-bandwidth communications codec by
independent studies and is widely deployed. AAC has been standardized by ISO and IEC as part
of the MPEG specifications.

Patent licenses for necessary patent claims for the FDK AAC Codec (including those of Fraunhofer)
may be obtained through Via Licensing (www.vialicensing.com) or through the respective patent owners
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the ISO/IEC MPEG audio standards. Please note that most manufacturers of Android devices already license
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software may already be covered under those patent licenses when it is used for those licensed purposes only.

Commercially-licensed AAC software libraries, including floating-point versions with enhanced sound quality,
are also available from Fraunhofer. Users are encouraged to check the Fraunhofer website for additional
applications information and documentation.

2.    COPYRIGHT LICENSE

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This FDK AAC Codec software is provided by Fraunhofer on behalf of the copyright holders and contributors
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5.    CONTACT INFORMATION

Fraunhofer Institute for Integrated Circuits IIS
Attention: Audio and Multimedia Departments - FDK AAC LL
Am Wolfsmantel 33
91058 Erlangen, Germany

www.iis.fraunhofer.de/amm
amm-info (at) iis.fraunhofer.de
----------------------------------------------------------------------------------------------------------- */

/***************************  Fraunhofer IIS FDK Tools  **********************

   Author(s):
   Description: Scaling operations

******************************************************************************/

#include "common_fix.h"

#include "genericStds.h"

/**************************************************
 * Inline definitions
 **************************************************/

#define SCALE_INLINE inline


#if defined(__mips__)	/* cppp replaced: elif */
#include "mips/scale.cpp"

#elif defined(__arm__)
#include "arm/scale_arm.cpp"

#endif

#ifndef FUNCTION_scaleValues_SGL
/*!
 *
 *  \brief  Multiply input vector by \f$ 2^{scalefactor} \f$
 *  \param len    must be larger than 4
 *  \return void
 *
 */
#define FUNCTION_scaleValues_SGL
SCALE_INLINE
void scaleValues(FIXP_SGL *vector,  /*!< Vector */
                 INT len,            /*!< Length */
                 INT scalefactor     /*!< Scalefactor */
                 )
{
  INT i;

  /* Return if scalefactor is Zero */
  if (scalefactor==0) return;

  if(scalefactor > 0){
    scalefactor = fixmin_I(scalefactor,(INT)(DFRACT_BITS-1));
    for (i = len&3; i--; )
    {
      *(vector++) <<= scalefactor;
    }
    for (i = len>>2; i--; )
    {
      *(vector++) <<= scalefactor;
      *(vector++) <<= scalefactor;
      *(vector++) <<= scalefactor;
      *(vector++) <<= scalefactor;
    }
  } else {
    INT negScalefactor = fixmin_I(-scalefactor,(INT)DFRACT_BITS-1);
    for (i = len&3; i--; )
    {
      *(vector++) >>= negScalefactor;
    }
    for (i = len>>2; i--; )
    {
      *(vector++) >>= negScalefactor;
      *(vector++) >>= negScalefactor;
      *(vector++) >>= negScalefactor;
      *(vector++) >>= negScalefactor;
    }
  }
}
#endif

#ifndef FUNCTION_scaleValues_DBL
/*!
 *
 *  \brief  Multiply input vector by \f$ 2^{scalefactor} \f$
 *  \param len must be larger than 4
 *  \return void
 *
 */
#define FUNCTION_scaleValues_DBL
SCALE_INLINE
void scaleValues(FIXP_DBL *vector,    /*!< Vector */
                 INT len,             /*!< Length */
                 INT scalefactor      /*!< Scalefactor */
                )
{
  INT i;

  /* Return if scalefactor is Zero */
  if (scalefactor==0) return;

  if(scalefactor > 0){
    scalefactor = fixmin_I(scalefactor,(INT)DFRACT_BITS-1);
    for (i = len&3; i--; )
    {
      *(vector++) <<= scalefactor;
    }
    for (i = len>>2; i--; )
    {
      *(vector++) <<= scalefactor;
      *(vector++) <<= scalefactor;
      *(vector++) <<= scalefactor;
      *(vector++) <<= scalefactor;
    }
  } else {
    INT negScalefactor = fixmin_I(-scalefactor,(INT)DFRACT_BITS-1);
    for (i = len&3; i--; )
    {
      *(vector++) >>= negScalefactor;
    }
    for (i = len>>2; i--; )
    {
      *(vector++) >>= negScalefactor;
      *(vector++) >>= negScalefactor;
      *(vector++) >>= negScalefactor;
      *(vector++) >>= negScalefactor;
    }
  }
}
#endif

#ifndef FUNCTION_scaleValues_DBLDBL
/*!
 *
 *  \brief  Multiply input vector src by \f$ 2^{scalefactor} \f$
 *          and place result into dst
 *  \param dst detination buffer
 *  \param src source buffer
 *  \param len must be larger than 4
 *  \param scalefactor amount of left shifts to be applied
 *  \return void
 *
 */
#define FUNCTION_scaleValues_DBLDBL
SCALE_INLINE
void scaleValues(FIXP_DBL *dst,       /*!< dst Vector */
                 const FIXP_DBL *src, /*!< src Vector */
                 INT len,             /*!< Length */
                 INT scalefactor      /*!< Scalefactor */
                )
{
  INT i;

  /* Return if scalefactor is Zero */
  if (scalefactor==0) {
	if (dst != src)
      FDKmemmove(dst, src, len*sizeof(FIXP_DBL));
  }
  else {

    if(scalefactor > 0){
      scalefactor = fixmin_I(scalefactor,(INT)DFRACT_BITS-1);
      for (i = len&3; i--; )
      {
        *(dst++) = *(src++) << scalefactor;
      }
      for (i = len>>2; i--; )
      {
        *(dst++) = *(src++) << scalefactor;
        *(dst++) = *(src++) << scalefactor;
        *(dst++) = *(src++) << scalefactor;
        *(dst++) = *(src++) << scalefactor;
      }
    } else {
      INT negScalefactor = fixmin_I(-scalefactor,(INT)DFRACT_BITS-1);
      for (i = len&3; i--; )
      {
        *(dst++) = *(src++) >> negScalefactor;
      }
      for (i = len>>2; i--; )
      {
        *(dst++) = *(src++) >> negScalefactor;
        *(dst++) = *(src++) >> negScalefactor;
        *(dst++) = *(src++) >> negScalefactor;
        *(dst++) = *(src++) >> negScalefactor;
      }
    }
  }
}
#endif

#ifndef FUNCTION_scaleValuesWithFactor_DBL
/*!
 *
 *  \brief  Multiply input vector by \f$ 2^{scalefactor} \f$
 *  \param len must be larger than 4
 *  \return void
 *
 */
#define FUNCTION_scaleValuesWithFactor_DBL
SCALE_INLINE
void scaleValuesWithFactor(
        FIXP_DBL *vector,
        FIXP_DBL factor,
        INT len,
        INT scalefactor
        )
{
  INT i;

  /* Compensate fMultDiv2 */
  scalefactor++;

  if(scalefactor > 0){
    scalefactor = fixmin_I(scalefactor,(INT)DFRACT_BITS-1);
    for (i = len&3; i--; )
    {
      *vector = fMultDiv2(*vector, factor) << scalefactor;
      vector++;
    }
    for (i = len>>2; i--; )
    {
      *vector = fMultDiv2(*vector, factor) << scalefactor; vector++;
      *vector = fMultDiv2(*vector, factor) << scalefactor; vector++;
      *vector = fMultDiv2(*vector, factor) << scalefactor; vector++;
      *vector = fMultDiv2(*vector, factor) << scalefactor; vector++;
    }
  } else {
    INT negScalefactor = fixmin_I(-scalefactor,(INT)DFRACT_BITS-1);
    for (i = len&3; i--; )
    {
      *vector = fMultDiv2(*vector, factor) >> negScalefactor;
      vector++;
    }
    for (i = len>>2; i--; )
    {
      *vector = fMultDiv2(*vector, factor) >> negScalefactor; vector++;
      *vector = fMultDiv2(*vector, factor) >> negScalefactor; vector++;
      *vector = fMultDiv2(*vector, factor) >> negScalefactor; vector++;
      *vector = fMultDiv2(*vector, factor) >> negScalefactor; vector++;
    }
  }
}
#endif /* FUNCTION_scaleValuesWithFactor_DBL */


/*******************************************

IMPORTANT NOTE for usage of getScalefactor()

If the input array contains negative values too, then these functions may sometimes return
the actual maximum value minus 1, due to the nature of the applied algorithm.
So be careful with possible fractional -1 values that may lead to overflows when being fPow2()'ed.

********************************************/


#ifndef FUNCTION_getScalefactorShort
/*!
 *
 *  \brief Calculate max possible scale factor for input vector of shorts
 *
 *  \return Maximum scale factor / possible left shift
 *
 */
#define FUNCTION_getScalefactorShort
SCALE_INLINE
INT getScalefactorShort(const SHORT *vector, /*!< Pointer to input vector */
                        INT len              /*!< Length of input vector */
                       )
{
  INT i;
  SHORT temp, maxVal = 0;

  for(i=len;i!=0;i--){
    temp = (SHORT)(*vector++);
    maxVal |= (temp^(temp>>(SHORT_BITS-1)));
  }

  return fixmax_I((INT)0,(INT)(fixnormz_D((INT)maxVal) - (INT)1 - (INT)(DFRACT_BITS - SHORT_BITS)));
}
#endif

#ifndef FUNCTION_getScalefactorPCM
/*!
 *
 *  \brief Calculate max possible scale factor for input vector of shorts
 *
 *  \return Maximum scale factor
 *
 */
#define FUNCTION_getScalefactorPCM
SCALE_INLINE
INT getScalefactorPCM(const INT_PCM *vector, /*!< Pointer to input vector */
                      INT len,               /*!< Length of input vector */
                      INT stride
                      )
{
  INT i;
  INT_PCM temp, maxVal = 0;

  for(i=len;i!=0;i--){
    temp = (INT_PCM)(*vector); vector+=stride;
    maxVal |= (temp^(temp>>((sizeof(INT_PCM)*8)-1)));
  }
  return fixmax_I((INT)0,(INT)(fixnormz_D((INT)maxVal) - (INT)1 - (INT)(DFRACT_BITS - SAMPLE_BITS)));
}
#endif

#ifndef FUNCTION_getScalefactorShort
/*!
 *
 *  \brief Calculate max possible scale factor for input vector of shorts
 *  \param stride, item increment between vector members.
 *  \return Maximum scale factor
 *
 */
#define FUNCTION_getScalefactorShort
SCALE_INLINE
INT getScalefactorShort(const SHORT *vector, /*!< Pointer to input vector */
                        INT len,             /*!< Length of input vector */
                        INT stride
                       )
{
  INT i;
  SHORT temp, maxVal = 0;

  for(i=len;i!=0;i--){
    temp = (SHORT)(*vector); vector+=stride;
    maxVal |= (temp^(temp>>(SHORT_BITS-1)));
  }

  return fixmax_I((INT)0,(INT)(fixnormz_D((INT)maxVal) - (INT)1 - (INT)(DFRACT_BITS - SHORT_BITS)));
}
#endif

#ifndef FUNCTION_getScalefactor_DBL
/*!
 *
 *  \brief Calculate max possible scale factor for input vector
 *
 *  \return Maximum scale factor
 *
 *  This function can constitute a significant amount of computational complexity - very much depending on the
 *  bitrate. Since it is a rather small function, effective assembler optimization might be possible.
 *
 */
#define FUNCTION_getScalefactor_DBL
SCALE_INLINE
INT getScalefactor(const FIXP_DBL *vector, /*!< Pointer to input vector */
                   INT len)                /*!< Length of input vector */
{
  INT i;
  FIXP_DBL temp, maxVal = (FIXP_DBL)0;

  for(i=len;i!=0;i--){
    temp = (LONG)(*vector++);
    maxVal |= (FIXP_DBL)((LONG)temp^(LONG)(temp>>(DFRACT_BITS-1)));
  }

  return fixmax_I((INT)0,(INT)(fixnormz_D(maxVal) - 1));
}
#endif

#ifndef FUNCTION_getScalefactor_SGL
#define FUNCTION_getScalefactor_SGL
SCALE_INLINE
INT getScalefactor(const FIXP_SGL *vector, /*!< Pointer to input vector */
                   INT len)                /*!< Length of input vector */
{
  INT i;
  SHORT temp, maxVal = (FIXP_SGL)0;

  for(i=len;i!=0;i--){
    temp = (SHORT)(*vector++);
    maxVal |= (temp^(temp>>(FRACT_BITS-1)));
  }

  return fixmax_I((INT)0,(INT)(fixnormz_D(FX_SGL2FX_DBL((FIXP_SGL)maxVal)) - 1));
}
#endif