Loading...

A Deconvolution Method Based on Total Variation Using Spatially Variant PSF Estimation for OCT Image Quality Enhancement

Almasganj, Mohammad | 2016

568 Viewed
  1. Type of Document: M.Sc. Thesis
  2. Language: Farsi
  3. Document No: 49463 (05)
  4. University: Sharif University of Technology
  5. Department: Electrical Engineering
  6. Advisor(s): Fatemizadeh, Emad; Nasiri Avanaki, Mohammad Reza
  7. Abstract:
  8. Optical Coherence Tomography (OCT) has a great potential to elicit clinically useful information from tissues due to its high axial and transversal resolution. In practice, an OCT setup cannot reach to its theoretical resolution due to imperfections of its components, which make its images blurry. The blurriness is different alongside regions of image, thus they cannot be modeled by a unique point spread function (PSF). In this paper, we investigate the use of solid phantoms to estimate the PSF of each sub-region of imaging system. We then utilize Lucy-Richardson, steepest descent (SD) and total variation (TV) based iterative deconvolution methods for mitigating occurred spatially variant blurriness. We then proposed some improvements for total variation based deconvolution method to yield better results. It is shown that the improved TV based method will sharpen the OCT images better than other approaches, in addition to superior eficacy in suppressing the noise. The performance of proposed algorithm is tested on 2 skin tissues, showing SNR improvement by 5.16 and 4.91 dB respectively. It is also tested on various samples, including several test images and the phantom itself, demonstrating qualitatively and quantitatively the advantage of improved TV based deconvolution method using spatially-variant PSF for enhancing image quality
  9. Keywords:
  10. Deconvolution ; Total Variation ; Steepest Descent Method ; Point Spread Function ; Optical Coherence Tomography ; Solid Phantom ; Lucy-Richardson Deconvolution ; Image Enhancement

 Digital Object List

 Bookmark

No TOC