omxsp_iir_biquaddirect_s16.c

The OpenMAX DL (Development Layer) APIs contain a comprehensive set of audio, video, signal processi

/**
 * 
 * File Name:  omxSP_IIR_BiQuadDirect_S16.c
 * OpenMAX DL: v1.0.2
 * Revision:   10586
 * Date:       Wednesday, March 5, 2008
 * 
 * (c) Copyright 2007-2008 ARM Limited. All Rights Reserved.
 * 
 * 
 *
 * Description:
 * This file contains module for block biquad IIR filtering
 *
 */
 
#include "omxtypes.h"
#include "armOMX.h"
#include "omxSP.h"

#include "armCOMM.h"

/**
 * Function:  omxSP_IIR_BiQuadDirect_S16   (2.2.3.3.1)
 *
 * Description:
 * Block biquad IIR filtering for 16-bit data type. This function applies the 
 * direct form II biquad IIR cascade defined by the coefficient vector pTaps 
 * to a vector of input data.  The internal accumulator width must be at least 
 * 32 bits, and the result is saturated if the operation produces a value 
 * outside the range of a signed 16-bit integer, i.e., the output will 
 * saturate to 0x8000 (-32768) for a negative overflow or 0x7fff (32767) for a 
 * positive overflow.  The result is undefined if any of the partially 
 * accumulated values exceeds the range of a signed 32-bit integer. 
 *
 * Input Arguments:
 *   
 *   pSrc - pointer to the vector of input samples to which the 
 *            filter is applied 
 *   len - the number of samples contained in both the input and output 
 *            vectors 
 *   pTaps - pointer to the 6P -element vector that contains the combined 
 *            numerator and denominator filter coefficients from the biquad 
 *            cascade. Coefficient scaling and coefficient vector organization 
 *            should follow the conventions described above. The value of the 
 *            coefficient scaleFactor exponent must be non-negative. (sfp>=0). 
 *   numBiquad - the number of biquads contained in the IIR filter cascade: 
 *            (P) 
 *   pDelayLine - pointer to the 2P -element filter memory buffer (state). 
 *            The user is responsible for allocation, initialization, and 
 *            de-allocation. The filter memory elements are initialized to 
 *            zero in most applications. 
 *
 * Output Arguments:
 *   
 *   pDst - pointer to the vector of filtered output samples 
 *
 * Return Value:
 *    
 *    OMX_Sts_NoErr - no error 
 *    OMX_Sts_BadArgErr - bad arguments; returned if one or more of the 
 *              following is true: 
 *    -    one or more of the following pointers is NULL: pSrc, pDst, 
 *              pTaps, or pDelayLine. 
 *    -    len < 0 
 *    -    numBiquad < 1 
 *    -    pTaps[3+n*6] < 0, for 0 <= n < numBiquad (negative scaling) 
 *
 */




OMXResult omxSP_IIR_BiQuadDirect_S16(
     const OMX_S16 * pSrc,
     OMX_S16 * pDst,
     OMX_INT len,
     const OMX_S16 * pTaps,
     OMX_INT numBiquad,
     OMX_S32 * pDelayLine
 )
{

    OMXResult errorCode = OMX_Sts_NoErr;

    /* Argument Check */
    armRetArgErrIf( pSrc       == NULL, OMX_Sts_BadArgErr);
    armRetArgErrIf( pDst       == NULL, OMX_Sts_BadArgErr);
    armRetArgErrIf( pDelayLine == NULL, OMX_Sts_BadArgErr);
    armRetArgErrIf( pTaps      == NULL, OMX_Sts_BadArgErr);
    armRetArgErrIf( len       <= 0    , OMX_Sts_BadArgErr);
    armRetArgErrIf( numBiquad <= 0    , OMX_Sts_BadArgErr);
    

    /* Processing */
    while(len != 0)
    {
        errorCode = omxSP_IIROne_BiQuadDirect_S16(
                        *pSrc,
                        pDst,
                        pTaps,
                        numBiquad,
                        pDelayLine);

        armRetArgErrIf( errorCode != OMX_Sts_NoErr, errorCode);

        pSrc++;
        pDst++;
        
        len--;
        
    }/*end while(len != 0)*/

    return OMX_Sts_NoErr;

}

/* End of File */