Performance evaluation of Frequency Analysis Descriptors for Dynamic Speckle

A. L. DAI PRA; L. I. PASSONI; G. H. SENDRA; H.J. RABAL; M. TRIVI

Porto

Congreso; 8th Iberoamerican Optics Meeting and 11th Latin American Meeting on Optics, Lasers, and Applications; 2013

Sociedad Portuguesa de Optica

Dynamic speckle patterns are observed when a rough surface illuminated by a laser beam presents some type of local movement. The activity appears when the sample changes its properties due to diverse physical behavior. Many descriptors have been developed to characterize dynamic speckle, several of them are heuristic and a few based on physical reasons. In this work we compare the performance of some of Frequency Analysis Descriptors for Dynamic Speckle, for example Energy of spectral band (ESB), High to Low Ratio (HLR) of the Power Spectral Density, Mean frequency (MF), Cutoff frequency (CF), Shannon Entropy (SE) of the Power Spectrum Density and Discrete Wavelet Transform Entropy (DWTE) We apply them to controlled numerical simulations to evaluate the linearity of the frequency descriptors with the simulated velocity and their performance with respect to the quantity of images processed. Also the computational cost will be considered. Results are shown with advantages and shortcomings comment. The coefficient of variation and correlation, the processing time, and the relative differences of their values for different quantity of samples are presented for each descriptor.