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DelayNChanSmoothed

Overview

Module with different time delay for each channel specified in samples

Discussion

This time delay module has multiple input and multiple output channels. The delay in samples of each output channel can be independently set by the currentDelay array. The initial number of channels is specified at construction time and this also equals the length of the currentDelay array. Actual size of the currentDelay and numChannels argument is updated in the prebuild function based on the channel count in the input pin . Delays are specified in samples 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 in samples per channel is specified by the currentDelay array. Delays can be adjusted at run-time. The module applies smooth cross fading when adjusting the currentDelay at run-time.

Module Pack

Advanced

ClassID

classID = 1393

Type Definition

typedef struct _ModuleDelayNChanSmoothed
{
ModuleInstanceDescriptor instance;            // Common Audio Weaver module instance structure
FLOAT32 smoothingTime;                        // Time constant of the cross fading process
FLOAT32 oldGain;                              // Gain parameter for cross fading.
FLOAT32 newGain;                              // Gain parameter for cross fading.
INT32 fadingDone;                             // State variable to implement cross fading.
INT32 maxDelay;                               // Maximum delay, in samples.
INT32 stateHeap;                              // Heap in which to allocate memory.
FLOAT32 smoothingCoeff;                       // Smoothing coefficient for cross fading.
INT32* currentDelay;                          // Current delay per channel, in samples.
INT32* stateIndex;                            // Index of the oldest state variable in the array of state variables.
FLOAT32* state;                               // State variable array.
INT32* prevDelay;                             // State array to implement cross fading.
} ModuleDelayNChanSmoothedClass;

Variables

Properties

Name Type Usage isHidden Default Value Range Units
smoothingTime float parameter 0 10 0:1000 msec
oldGain float derived 0 1 Unrestricted
newGain float derived 0 0 Unrestricted
fadingDone int derived 0 0 0:1
maxDelay int const 1 100 Unrestricted samples
stateHeap int const 1 561 Unrestricted
smoothingCoeff float derived 1 0.002081 Unrestricted
currentDelay int* parameter 0 [1 x 1] 0:1:100 samples
stateIndex int* state 1 [1 x 1] Unrestricted
state float* state 1 [1 x 134] Unrestricted
prevDelay int* state 1 [1 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

Output Pins

Name out
Description audio output
Data Type float

Scratch Pins

Channel Count 1
Block size 32
Sample rate 48000

Matlab Usage

File Name: delaynchan_smoothed_module.m 
 M=delaynchan_smoothed_module(NAME, NUMCHANNELS, MAXDELAY, MEMHEAP) 
 Creates a multi-channel time delay. 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  
 per channel. The module applies smooth transition between delay time  
 changes. 

 Arguments: 
    NAME - name of the module. 
    NUMCHANNELS - number of channels for the module. 
    MAXDELAY - maximum delay, in samples. 
    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. 

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