The Audio Syntiant processing block extracts time and frequency features from a signal. It is similar to the Audio MFE but performs additional processing specific to the Syntiant NDP101/120 chip. This block can be used only with Syntiant targets.
Syntiant spectrogram of the sentence "Hello, World"
Audio Syntiant parameters
Log Mel-filterbank energy features
Frame length: The length of each frame in seconds
Frame stride: The step between successive frame in seconds
Filter number (fixed): The number of triangular filters applied to the spectrogram
FFT length (fixed): The FFT size
Low frequency (fixed): Lowest band edge of Mel-scale filterbanks
High frequency (fixed): Highest band edge of Mel-scale filterbanks
Coefficient: Pre-emphasis coefficient
Features extractor: Syntiant method to generate features, choose accordingly to your chip
How does the Syntiant block work?
The features' extractions is a proprietary algorithm from Syntiant. However parameters are very close to the Audio MFE. Pre-emphasis coefficient is applied first to amplify higher frequencies. The signal is then divided in overlapping frames, defined by the Frame length and Frame stride to extract speech features.
The Audio Syntiant block only supports a 16 kHz frequency. You can adjust the sampling frequency in the "Create Impulse" section.