Overview

Smooth scaler with independent gain per channel with gain (in linear units) is taken from an input pin

Discussion

The Scaler Control module smoothly scales multichannel input data by a independent gain value. The first pin is the control pin with gain values. The size of the control pin (i.e. number of gain values) is same as number of channels on input data. So the module has 2 input pins and 1 output pin Internally, currentGain represents the instantaneous smoothed gain that is applied. currentGain exponentially approaches gain with a time constant equal to smoothingTime.

Type Definition

typedef struct _ModuleScalerNControl
{
    ModuleInstanceDescriptor instance;            // Common Audio Weaver module instance structure
    FLOAT32 smoothingTime;                        // Time constant of the smoothing process
    FLOAT32 smoothingCoeff;                       // Smoothing coefficient
    FLOAT32* currentGain;                         // Array of instantaneous linear gains, one per channel.
} ModuleScalerNControlClass;

Variables

Properties

Name	Type	Usage	isHidden	Default value	Range	Units
smoothingTime	float	parameter	0	10	0:1000	msec
smoothingCoeff	float	derived	1	0.002081	Unrestricted
currentGain	float*	state	0	[1 x 1]	-10:10	linear

Pins

Input Pins

Name: g

Description: linear gain to apply

Data type: float

Channel range: Unrestricted

Block size range: 1

Sample rate range: Unrestricted

Complex support: Real

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: scalern_control_module.m

 M=scalern_control_module(NAME, NUMCHANNELS)
 Creates a smoothly varying multi channel scaler module with gain as 
 control pin. The first pin is the control pin. Control pin has the same 
 number of channels as of audio pin to allow separate gain value per audio
 channel.
   Arguments:
    NAME - name of the module.
    NUMCHANNELS - Optional: number of channels. Normally determined
             during pin propagation. By default, NUMCHANNELS = 1