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Db10Approx

Overview

Converts from energy to decibels using a fast approximation

Discussion

Converts from energy to decibels using a fast polynomial approximation The function uses a 3rd order polynomial and the maximum error over the entire input range is 1.4e-5 dB.

Module Pack

Standard

ClassID

classID = 71

Type Definition

typedef struct _ModuleDb10Approx
{
ModuleInstanceDescriptor instance;            // Common Audio Weaver module instance structure
} ModuleDb10ApproxClass;

Pins

Input Pins

Name in
Description Input signal
Data type float
Channel range Unrestricted
Block size range Unrestricted
Sample rate range Unrestricted
Complex support Real

Output Pins

Name out
Description Output signal
Data Type float

Matlab Usage

File Name: db10_approx_module.m 
 M=db10_approx_module(NAME) 
 Creates an Audio Weaver module that computes the function 10*log10(x) 
 using a polynomial approximation.  This converts from energy to decibels. 
    NAME - name of the module. 

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