DelayNChanMsec

Overview

Module with different time delay for each channel specified in milliseconds

Discussion

This time delay module has multiple input and multiple output channels. The delay of each output channel can be independently set by the currentDelayTime array. The initial number of channels is specified at construction time and this also equals the length of the currentDelayTime array. Actual size of the currentDelayTime is updated in the prebuild function. Delays are specified in milliseconds and are in the range of [0 MAXDELAY].

At construction time, you specify the maximum delay (maxDelay) of the module. The variable, maxDelay determines the size of the internal state buffer. The size of the internal state buffer equals (maxDelay+1)*numChannels samples. The delay time per channel is specified by the currentDelayTime array.

delay = floor( currentDelay * SR ) / SR

Delays can be adjusted at run-time. However, the module is not smoothly updating and you may get audible clicks when adjusting the currentDelay at run-time.

Type Definition

CODE

typedef struct _ModuleDelayNChanMsec
{
    ModuleInstanceDescriptor instance;            // Common Audio Weaver module instance structure
    FLOAT32 maxDelayTime;                         // Maximum delay, in milliseconds.
    INT32 stateHeap;                              // Heap in which to allocate memory. Used to pass the value to internal delaynchan module.
    INT32 maxDelay;                               // Max delay in samples. Used to pass the value to internal delaynchan module.
    FLOAT32* currentDelayTime;                    // Current delay, in milliseconds.
    awe_modDelayNChanInstance *delay; // Module with different time delay for each channel specified in samples
} ModuleDelayNChanMsecClass;

Variables

Properties

Name	Type	Usage	isHidden	Default value	Range	Units
maxDelayTime	float	const	0	10	0:10	msec
stateHeap	int	const	1	561	Unrestricted
maxDelay	int	const	1	480	Unrestricted
currentDelayTime	float*	parameter	0	[1 x 1]	0:10	msec

Pins

Input Pins

Name: in

Description: Audio Input

Data type: {float, int, fract32}

Channel range: Unrestricted

Block size range: Unrestricted

Sample rate range: Unrestricted

Complex support: Real

Output Pins

Name: out

Description: audio output

Data type: {float, int, fract32}

MATLAB Usage

File Name: delaynchan_msec_module.m

CODE

 SYS=delaynchan_msec_module(NAME, NUMCHANNELS, MAXDELAY, MEMHEAP)
 Creates a multi-channel time delay in which the delay times are specified
 in milliseconds. The module has a multichannel input pin
 and an multichannel output pin. Each output channel is a delayed
 version of the corresponding input channel with different delay times 
 for each channel.
 
 Arguments:
    NAME - name of the module.
    NUMCHANNELS - number of channels for the module.
    MAXDELAY - maximum delay, in milliseconds.
    MEMHEAP - specifies the memory heap to use to allocate the main
         state buffer. This is a string and follows the memory allocation
         enumeration in Framework.h. Allowable values are:
            'AWE_HEAP_FAST' - always use internal DM memory.
            'AWE_HEAP_FASTB' - always use internal PM memory.
            'AWE_HEAP_SLOW' - always use external memory.
            'AWE_HEAP_FAST2SLOW' - use internal memory. If this fails
               then use external memory (the default).
            'AWE_HEAP_FASTB2SLOW' - use internal memory. If this fails
               then use external memory.