BROWSE
Detail
Journal Article
Dynamic Speckle Analysis with Coarse Quantization of the Raw Data
Cited 9 time in 
Share 
Share
- Authors
- Elena Stoykova, Dimana Nazarova, Lian Nedelchev, Branimir Ivanov, Blaga Blagoeva, Kwan-Jung Oh, Joongki Park
- Issue Date
- 2020-03
- Citation
- Applied Optics, v.59, no.9, pp.2810-2819
- ISSN
- 1559-128X
- Publisher
- Optical Society of America (OSA)
- Language
- English
- Type
- Journal Article
- Abstract
- Analysis of dynamic speckle formed on the surface of diffusely reflecting objects under laser illumination is a noncontact method for inspection of speed of processes. The paper deals with intensity-based implementation of the method that relies on statistical processing of correlated in time sequences of speckle images. A two-dimensional activity map is built for each sequence to visualize regions of different speed on the object surface at a given instant. A great number of images is required to track a process in time. We propose data compression by coarse quantization of the raw speckle data. Efficacy of quantization is analyzed by simulation and experiment for low- and high-contrast speckle patterns with bell-shaped and long-tailed distributions of intensity, respectively. Nonuniformquantization is proposed for long-tailed speckle intensity distributions.Decreasing the bit depth from8 to 4 causes no change in the probability density function of the activity estimate.
- KSP Keywords
- Activity map, Bit-depth, Coarse Quantization, Data analysis, Dynamic speckle, High contrast, Intensity distributions, Laser illumination, Long-tailed distributions, Probability Density Function, Simulation and experiment