arm_fir_interpolate_init_q15.c

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/*-----------------------------------------------------------------------------      
* Copyright (C) 2011 ARM Limited. All rights reserved. 
*      
* $Date:        15. December 2011   
* $Revision:    V2.0.0  
*      
* Project:      Cortex-R DSP Library 
* Title:        arm_fir_interpolate_init_q15.c      
*      
* Description:  Q15 FIR interpolator initialization function      
*      
* Target Processor:          Cortex-R4/R5
*
* Version 1.0.0 2011/03/08
*     Alpha release.
*
* Version 1.0.1 2011/09/30
*     Beta release.
*
* Version 2.0.0 2011/12/15
*     Final release. 
* 
* ---------------------------------------------------------------------------*/     
#include "arm_math.h"     
     
arm_status arm_fir_interpolate_init_q15(     
  arm_fir_interpolate_instance_q15 * S,     
  uint8_t L,     
  uint16_t numTaps,     
  q15_t * pCoeffs,     
  q15_t * pState,     
  uint32_t blockSize)     
{     
  arm_status status;     
     
  /* The filter length must be a multiple of the interpolation factor */     
  if((numTaps % L) != 0u)     
  {     
    /* Set status as ARM_MATH_LENGTH_ERROR */     
    status = ARM_MATH_LENGTH_ERROR;     
  }     
  else     
  {     
     
    /* Assign coefficient pointer */     
    S->pCoeffs = pCoeffs;     
     
    /* Assign Interpolation factor */     
    S->L = L;     
     
    /* Assign polyPhaseLength */     
    S->phaseLength = numTaps / L;     
     
    /* Clear state buffer and size of buffer is always phaseLength + blockSize - 1 */     
    memset(pState, 0,     
           (blockSize + ((uint32_t) S->phaseLength - 1u)) * sizeof(q15_t));     
     
    /* Assign state pointer */     
    S->pState = pState;     
     
    status = ARM_MATH_SUCCESS;     
  }     
     
  return (status);     
     
}