ClipIndicator

Overview

Detects clipping by measuring when a signal level exceeds a specified threshold

Discussion

Module Pack

Standard

ClassID

classID = 106

Type Definition

typedef struct _ModuleClipIndicator
{
ModuleInstanceDescriptor instance;            // Common Audio Weaver module instance structure
FLOAT32 threshold;                            // Threshold in dB above which clipping occurs.
FLOAT32 attackTime;                           // Attack time of the clipping detector. Specifies how quickly the value is allowed to rise.
FLOAT32 releaseTime;                          // Release time of the clipping detector. Specifies how quickly the value is allowed to decay.
FLOAT32 thresholdCoeff;                       // Internal derived parameter which equals undb20(threshold).
FLOAT32 attackCoeff;                          // Internal coefficient that realizes the attack time.
FLOAT32 releaseCoeff;                         // Internal coefficient that realizes the release time.
FLOAT32* value;                               // Internal array of envelope follower state variables, one per channel.
INT32* isClipping;                            // Boolean array of clipping values, one per channel.
} ModuleClipIndicatorClass;

Variables

Properties

Name	Type	Usage	isHidden	Default Value	Range	Units
threshold	float	parameter	0	0	-100:20	dB
attackTime	float	parameter	0	5	0:1000	msec
releaseTime	float	parameter	0	100	0:10000	msec
thresholdCoeff	float	derived	1	1	Unrestricted	linear
attackCoeff	float	derived	1	0.1248	Unrestricted
releaseCoeff	float	derived	1	0.006644	Unrestricted
value	float*	state	1	[1 x 1]	0:1000
isClipping	int*	state	0	[1 x 1]	0:1:1

Pins

Input Pins


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

Scratch Pins


Channel Count	1
Block size	32
Sample rate	48000

Matlab Usage

File Name: clip_indicator_module.m 
 M=clip_indicator_module(NAME) 
 Creates a module that tests for clipping of an audio signal. The 
 clipping threshold is programmable.  

 Arguments: 
    NAME - name of the module.