PDF

Overview

pdf of data

Discussion

The PDF module builds a histogram of incoming data and allows you to freeze the histogram with an input pin. It also provides optional smoothing as well as an optional reset pin. A histogram is a graphical representation showing a visual impression of the distribution of data values. A histogram is essentially a table in which each entry represents the number of times that the input sample values fell in a particular range.

Unlike the Histogram module, the PDF module calculates the bin spacing based on the higherBinEdge and lowerBinEdge variables ((higherBinEdge - lowerBinEdge) / numBins). Set these variables to change the bin spacing of your PDF module’s histogram.

Connect an audio signal that you wish to analyze by wiring into input pin 1.

Conenct a BooleanSource module to the freeze pin and toggle to freeze the histogram in its current state.

(OPTIONAL) Enable the reset pin in the Arguments tab. Connect a BooleanSource module to the optional reset pin to clear the histogram data.

Module Pack

Advanced

ClassID

classID = 1370

Type Definition

typedef struct _ModulePDF
{
ModuleInstanceDescriptor instance;            // Common Audio Weaver module instance structure
INT32 numBins;                                // Number of bins
INT32 controllableResetPin;                   // Controlling Reset Pin
FLOAT32 lowerBinEdge;                         // Specifies the lowest bin in the histogram
FLOAT32 higherBinEdge;                        // Specifies the highest bin in the histogram
FLOAT32 smoothingTime;                        // The smoothing time of the PDF in ms
FLOAT32 alpha;                                // Forgetting factor
FLOAT32 binSpacing;                           // BinSpacing
INT32 reset;                                  // Boolean parameter to reset the pdf.
FLOAT32* binCenter;                           // indices
FLOAT32* previousOut;                         // previous output.
INT32* hist;                                  // init hist.
} ModulePDFClass;

Variables

Properties

Name	Type	Usage	Default Value	Range
numBins	int	const	32	Unrestricted
controllableResetPin	int	const	1	Unrestricted
lowerBinEdge	float	parameter	-1	Unrestricted
higherBinEdge	float	parameter	1	Unrestricted
smoothingTime	float	parameter	1000	0:10000
alpha	float	derived	0.0006664	Unrestricted
binSpacing	float	derived	0.0625	Unrestricted
reset	int	parameter	0	0:1
binCenter	float*	derived	[32 x 1]	Unrestricted
previousOut	float*	state	[32 x 1]	Unrestricted
hist	int*	state	[32 x 1]	Unrestricted

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


Name	freeze
Description	input freeze
Data type	int
Channel range	1
Block size range	1
Sample rate range	Unrestricted
Complex support	Real


Name	reset
Description	input reset
Data type	int
Channel range	1
Block size range	1
Sample rate range	Unrestricted
Complex support	Real

Output Pins


Name	out
Description	Audio output
Data Type	float

Matlab Usage

File Name: pdf_module.m