WaveLoopPlayerRAM
Overview
Periodic WAV playback supporting pitch shifting
Discussion
This module outputs wave data in loop mode. User has to specify the file name as an argument. Along with the above parameters, the playback functionality can be enabled from the control input pin, 1 - Enable and 0 - Disable.
The module supports multichannel such that, if the wave file has more channels than provided to the module argument then only channels up to output pin channels will be used. If the wave file has less channels than output pin channels, then the remaining output channels will be muted.
Type Definition
typedef struct _ModuleWaveLoopPlayerRAM
{
ModuleInstanceDescriptor instance; // Common Audio Weaver module instance structure
INT32 smoothingTime; // Time constant of the pitch smoothing process
INT32 smoothingFactor; // Update rate for smoothing coeffs (per block)
INT32 startDelay; // Starting delay value in samples
INT32 enable; // En/Disable playback. Resets sample position to startDelay value upon stop
INT32 interpMode; // Linear or cubic interpolation
FLOAT32 normRate; // Rate of data used to compute the ratio for normalized players
FLOAT32 maxRate; // Highest allowed rate of playback that can be specified
INT32 waveLength; // Number of samples in currently loaded file
INT32 fIndex; // Current index in the wave file
FLOAT32 fIndexFract; // Current fract index in the wave file
FLOAT32 currentFStep; // Current (smoothed) rate at which audio is read from the input buffer
INT32 waveSR; // Actual sample rate of the wave file.
INT32 waveNumChannels; // Number of channels in the wave file.
FLOAT32 scaleFactor; // Scale factor for playback rate
FLOAT32 smoothingCoeff; // Smoothing (pitch) coefficient
UINT32 pinID; // Specifies which control pins are available.
INT32* waveBuffer; // Data transferred from PC to target DSP via this buffer.
} ModuleWaveLoopPlayerRAMClass;
Variables
Properties
Name | Type | Usage | isHidden | Default value | Range | Units |
smoothingTime | int | parameter | 0 | 10 | 0:1000 | msec |
smoothingFactor | int | parameter | 0 | 4 | 1:512 | |
startDelay | int | parameter | 0 | 0 | Unrestricted | |
enable | int | state | 0 | 1 | 0:1 | |
interpMode | int | const | 0 | 2 | Unrestricted | |
normRate | float | const | 0 | 1 | Unrestricted | |
maxRate | float | const | 0 | 2 | Unrestricted | |
waveLength | int | derived | 0 | 8976 | Unrestricted | |
fIndex | int | state | 0 | 0 | Unrestricted | |
fIndexFract | float | state | 0 | 0 | Unrestricted | |
currentFStep | float | state | 0 | 1 | Unrestricted | |
waveSR | int | derived | 1 | 48000 | Unrestricted | |
waveNumChannels | int | derived | 1 | 1 | Unrestricted | |
scaleFactor | float | derived | 1 | 1 | Unrestricted | |
smoothingCoeff | float | derived | 1 | 0.1248 | Unrestricted | |
pinID | uint | const | 1 | 3 | Unrestricted | |
waveBuffer | int* | parameter | 0 | [4490 x 1] | Unrestricted |
Pins
Input Pins
Name: enable
Description: Flag to enable playback
Data type: int
Channel range: 1
Block size range: 1
Sample rate range: Unrestricted
Complex support: Real
Name: fRatio
Description: Specifies sample rate ratio
Data type: float
Channel range: 1
Block size range: 1
Sample rate range: Unrestricted
Complex support: Real
Output Pins
Name: audio
Description: output data
Data type: float
Name: isPlaying
Description: playing state
Data type: int
MATLAB Usage
File Name: wave_loop_player_ram_module.m