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DelayNChan

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

Module Pack

Advanced

ClassID

classID = 1367

Type Definition

typedef struct _ModuleDelayNChan
{
ModuleInstanceDescriptor instance;            // Common Audio Weaver module instance structure
INT32 maxDelay;                               // Maximum delay, in samples.
INT32 stateHeap;                              // Heap in which to allocate memory.
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.
void * hardware_specific_struct_pointer;      // Usually NULL, but for optimizations, this may point to a struct that varies based on the target platform
} ModuleDelayNChanClass;

Variables

Properties

Name Type Usage isHidden Default Value Range Units
maxDelay int const 1 100 Unrestricted samples
stateHeap int const 1 561 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 103] Unrestricted
hardware_specific_struct_pointer void * state 1 Unrestricted

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_module.m 
 M=delaynchan_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. 

 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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