MultiplexorV2Fract32

Overview

General purpose multiplexor

Discussion

This module has a variable number of input pins and routes (or copies) one of these pins to the output, while smoothly varying the multiplexor module with fade time between input pin transitions.

This module has built in smoothing to prevent audible clicks when transitioning between input pins.

An optional control pin (Ctrl) is provided (enabled under module Arguments using isControl = true). The first sample value on this control pin is used as the index for the multiplexor input pins; all other values are ignored. The control pin contains an integer value in the range 0 to N-1, where N is the number of audio inputs. If the control value is outside of the allowable range it is clipped to max index (N-1).

Only when the control pin is disabled (isControl = false) the index for the multiplexor input pins can be selected from the Module Inspector (Double clicking on the Module on the designer canvas)

Each audio input pin must have the same number of channels and block size.

Type Definition

CODE

typedef struct _ModuleMultiplexorV2Fract32
{
    ModuleInstanceDescriptor instance;            // Common Audio Weaver module instance structure
    INT32 index;                                  // Specifies which input pin to route to the output. The index is zero based.
    FLOAT32 smoothingTime;                        // Time constant of the smoothing process
    FLOAT32 fadeTime;                             // Silence time in crossfade
    INT32 isControl;                              // Indicates if the index is controlled by an external signal
    fract32 smoothingCoeffFract32;                // Smoothing coefficient
    fract32 oldSrcGainFract32;                    // Instanteous gain being applied to the old source. This is an internal variable used in the smoothing process
    fract32 newSrcGainFract32;                    // Instanteous gain being applied to the new source. This is an internal variable used in the smoothing process
    INT32 fadeState;                              // State variable for determining when to transitioning between inputs
    INT32 fadeStateInit;                          // Derived from fadeTime, determines number of blocks to wait before switching input pins
    INT32 oldIndex;                               // This is index that is currently being used and the module smoothly transitions to index
    INT32 newIndex;                               // This is index that is currently being used and the module smoothly transitions to index
} ModuleMultiplexorV2Fract32Class;

Variables

Properties

Name	Type	Usage	isHidden	Default value	Range	Units
index	int	parameter	0	0	0:2
smoothingTime	float	parameter	0	10	0:100	msec
fadeTime	float	parameter	0	10	0:100	msec
isControl	int	const	1	1	Unrestricted
smoothingCoeffFract32	fract32	derived	1	0.002081	Unrestricted
oldSrcGainFract32	fract32	state	1	0	Unrestricted
newSrcGainFract32	fract32	state	1	0	Unrestricted
fadeState	int	state	1	0	Unrestricted
fadeStateInit	int	derived	1	983100	Unrestricted
oldIndex	int	parameter	1	0	Unrestricted
newIndex	int	parameter	1	0	Unrestricted

Pins

Input Pins

Name: Ctrl

Description: Input pin control signal

Data type: int

Channel range: Unrestricted

Block size range: Unrestricted

Sample rate range: Unrestricted

Complex support: Real

Name: in1

Description: Input signal

Data type: fract32

Channel range: Unrestricted

Block size range: Unrestricted

Sample rate range: Unrestricted

Complex support: Real

Name: in2

Description: Input signal

Data type: fract32

Channel range: Unrestricted

Block size range: Unrestricted

Sample rate range: Unrestricted

Complex support: Real

Name: in3

Description: Input signal

Data type: fract32

Channel range: Unrestricted

Block size range: Unrestricted

Sample rate range: Unrestricted

Complex support: Real

Output Pins

Name: out

Description: Output signal

Data type: fract32

MATLAB Usage

File Name: multiplexor_v2_fract32_module.m

CODE

 M = multiplexor_v2_fract32_module(NAME, ISCONTROL, NUMINPINS)
 Creates a multiplexor module that seamlessly switches between inputs.
 The module has multiple input pins and switches from one input to another.
 The optional control pin is the first pin (when enabled) and determines
 which of N inputs is selected. The input pin is an integer value in the
 range 0 to N-1.
 Arguments:
    NAME - name of the module.
    ISCONTROL - enables or disables the control pin
    NUMINPINS - number of input pins.
 All input pins must have the same block size and number of channels.
 Note, this verson implements an optional smooth crossfade between inputs.