A temporal filtering method based on an infinite-impulse-response filter is presented to reduce speckle in optical
coherence tomography (OCT) images. This method works in a recursive way, linearly combining the current B-scan
image frame with a previously filtered one to generate a newly filtered image. Thus, it performs with less computational
complexity and time, compared to the finite-impulse-response filter based approach that typically averages multiple
stored frames. To achieve speckle noise reduction while avoiding image blurring caused by sample motion, the filter
coefficient is dynamically determined, depending on the parameters related to motion detection and image quality. We
used the mean-squared error (MSE) between two successive frames as a criterion to detect sample motion and changed
the filter coefficient when the MSE exceeded a certain threshold to prevent image blurring. The optimal coefficient and
motion detection threshold were chosen for achieving robust and unblurred images in our testbed configuration. In this
study, we analyzed the algorithm with OCT images acquired by a swept-source OCT system we built and also examined
that the method operated in real-time even via CPU processing. Results in our and conventional schemes are compared
by using various image quality metrics and by observing images. We found that the performance of speckle reduction
was quite promising and simultaneously the fine details of sample structures were preserved even with sample motion.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.