Overview

Computes long term min/max/max abs

Discussion

This module keeps track of the maximum (minimum, and maximum absolute value) seen on the input. This is useful, for example, for keeping track of peak signal levels. The state variable value holds the maximum value seen thus far.

The statisticsType variable configures which type of computation the block does: 0=Maximum, 1=Minimum, 2=Maximum Absolute Value.

An optional constructor argument OUTPUTVALUE specifies whether the computed statistic should be output on an output pin. By default, OUTPUTVALUE=0 and the statistic is only stored internally in instantaneousValue. The .reset variable is used to clear history and restart the calculation. The variable .reset is set to 1 when the module is first constructed.

Type Definition

typedef struct _ModuleRunningMinMaxFract32
{
    ModuleInstanceDescriptor instance;            // Common Audio Weaver module instance structure
    INT32 statisticsType;                         // Type of statistics needed.
    fract32 value;                                // Instantaneous output value.
    INT32 reset;                                  // Trigger pin to reset monitoring.
} ModuleRunningMinMaxFract32Class;

Variables

Properties

Pins

Input Pins

Name: in

Description: Audio input

Data type: fract32

Channel range: Unrestricted

Block size range: Unrestricted

Sample rate range: Unrestricted

Complex support: Real

Output Pins

Name: out

Description: State value output

Data type: fract32

MATLAB Usage

File Name: running_minmax_fract32_module.m

 M = running_minmax_fract32_module(NAME, OUTPUTVALUE)
 This module keeps track of the largest (or smallest) value in the
 input and stores this to the internal state variable value. The
 module uses all samples since the start of processing. A number of
 different statistics can be calculated based on the statisticsType
 parameter.
 
 Arguments:
    NAME - name of the module.
    OUTPUTVALUE - Boolean value which specifies whether the module has
         an output pin. If OUTPUTVALUE=0 (the default), then
         the module has no output pin. If OUTPUTVALUE=1, then
         the value variable is output as a single sample on the
         output pin.