Signal processing is the process of extracting distinguishing features from a raw biometric sample, which may include some or all of the following:
- signal or image normalization
- feature extraction
- quality assessment, and
- template creation.
Signal processing is
|“||[t]he processing of externally derived information-bearing signals by algorithms such as time compression, filtering, extraction, selection, correlation, convolution or transformations between domains (e.g., fast Fourier transform or Walsh transform).||”|