amf_agcnmaxabs_s.c

ADI SHARC DSP 音频算法标准模块库

// Copyright(c) 2005 Analog Devices, Inc. All Rights Reserved.
// This software is proprietary and confidential to Analog Devices, Inc. and its licensors.

// File    : $Id: //depot/development/visualaudio/modules/2.5.0/SHARC/Source/AMF_AGCNMaxAbs_S.c#3 $ 
// Part of : VisualAudio V2.5.0 
// Updated : $Date: 2006/10/12 $ by $Author: Fernando $



#include "AMF_AGCNMaxAbs_S.h"
#include <math.h>

void AMF_AGCNMaxAbs_S_Render(AMF_AGCNMaxAbs_S * restrict instance,float * restrict * buffers,int tickSize);

// NOTE: The C version of this function is for reference only (it is
//       intended just to show the general algorithm that the module
//       uses), and it may not have been fully tested
#if 0
SEG_MOD_FAST_CODE  void AMF_AGCNMaxAbs_S_Render(AMF_AGCNMaxAbs_S * restrict instance,float * restrict * buffers,int tickSize) {
    int numInputs = instance->b.inputPinCount;
    int i,j,k;
    float *out = buffers[numInputs];
    float *in;
    float absL, absR, maxLR;
#if 1
    in = buffers[0];
    // Could rewrite this so that aliasing is OK
    // but I suspect this formulation is faster.
    for (i=0,j=0; i<tickSize; i++,j+=2) {
        absL = fabsf(in[j]);
        absR = fabsf(in[j+1]);
        out[i] = fmaxf(absL, absR);
    }
    for (k=1; k<numInputs; k++) {
        in = buffers[k];
        for (i=0,j=0; i<tickSize; i++,j+=2) {
            absL = fabsf(in[j]);
            absR = fabsf(in[j+1]);
            maxLR = fmaxf(absL, absR);
            out[i] = fmaxf(out[i],maxLR);
        }
    }
#else
    // Alternative formulation that would allow aliasing:
    float val;
    for (i=0, j=0; i<tickSize; i++,j+=2) {
        val = 0.0;
        for (k=0; k<numInputs; k++) {
            val = fmaxf(val,fabs(buffers[k][j]));
            val = fmaxf(val,fabs(buffers[k][j+1]));
        }
        out[i] = val;
    }
#endif    
}
#endif

SEG_MOD_SLOW_CONST const AMF_ModuleVariableClass AMFClassAGCNMaxAbs_S = {
    AMFModuleClassFlag_VARIABLE_PIN_COUNT, // flags
    (AMF_RenderFunction) AMF_AGCNMaxAbs_S_Render,  // render function 
    (void *)0 // default
};