amf_panner.c

来自「ADI SHARC DSP 音频算法标准模块库」· C语言 代码 · 共 71 行

// 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_Panner.c#3 $ 
// Part of : VisualAudio V2.5.0 
// Updated : $Date: 2006/10/12 $ by $Author: Fernando $



#include "AMF_Panner.h"

#include "VA_GeneralHelperFunctions.h"

void AMF_Panner_Render(AMF_Panner * 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_Panner_Render(AMF_Panner * restrict instance,float * restrict * buffers,int tickSize) {
    int i,j;
    float cosSinSmoothing = instance->cosSinSmoothing;
    float oneMinusRate = 1.0 - cosSinSmoothing;
    float *in = buffers[0];
    float *out = buffers[1];
    float c0 = instance->cosTheta;
    float c1 = instance->sinTheta;
    float t0 = instance->cosThetaTarget * cosSinSmoothing;
    float t1 = instance->sinThetaTarget * cosSinSmoothing;

    for (i=0,j=0; i<tickSize; i++,j+=2) {
        // smooth Cos and Sin for pan
        c0 = c0 * oneMinusRate + t0;
        c1 = c1 * oneMinusRate + t1;

        out[j] = in[i] * c0;
        out[j+1] = in[i] * c1;
    }

    instance->cosTheta = c0;
    instance->sinTheta = c1;
}
#endif

SEG_MOD_SLOW_CONST const AMF_ModuleClass AMFClassPanner = {
    
    /* Flags */
    0,
     
    /* Render function */
    (AMF_RenderFunction)AMF_Panner_Render,  // render function 
    
    /* Default bypass */
    (void *)0,
        
    /* Input descriptor - 1 input, and it is mono. */
    1, 0,

    /* Output descriptor - 1 output, and it is stereo. */
    1, 1,
};

// Class-specific helper functions

// see AMF_SetPannerTheta() in VA_GeneralHelperFunctions.c
// also macros in AMF_Panner.h
//    AMF_Panner_SetPannerTheta()
//    AMF_Panner_SetPannerValue()