Naoki Chiba

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SUMMARY We propose an automatic image mosaicing method which can construct a panoramic image from a collection of digital still images. Our method is fast and robust enough to process a nonplanar scene with unrestricted camera motion. The method includes the following two techniques. First, we use a multiresolution patch-based optical flow estimation for(More)
BACKGROUND Laser speckle flowgraphy (LSFG) enables noninvasive quantification of the retinal circulation in glaucoma patients. In this study, we tested the intrasession reproducibility of LSFG-NAVI, a modified LSFG technique. METHODS Sixty-five eyes from 33 subjects (male (M):female (F) = 17:16) with a mean age of 49.4 ± 11.2 years were examined in this(More)
Parameter indeterminacies are inherent in 3D computer vision. We show in this thesis that how they are treated can have significant impact on the accuracy of the estimated 3D structure. However, there has not been a general and convenient method available for representing and analyzing the indeterminacies and their effects on accuracy. Consequently , up to(More)
We propose an automatic line tracking method which can deal with broken or closely-spaced line segments more accurately than previous methods over an image sequence. The method uses both grey scale information of the original images and geometric attributes of line segments. By using our hierarchical optical ow technique, we can get a good prediction of(More)
BACKGROUND The purpose of this study was to investigate the correlations between microcirculation in the optic disc, average peripapillary retinal nerve fiber layer thickness cupping parameters, and visual field defects in glaucoma patients with the generalized enlargement disc type. METHODS A total of 38 eyes from 38 glaucoma patients with the(More)
The Kyoto global consensus report on Helicobacter pylori (H. pylori) gastritis has had a great effect on the field of H. pylori studies worldwide. For the first time H. pylori gastritis was defined entirely as an infectious disease and H. pylori-associated dyspepsia as a new category of organic dyspepsia apart from functional dyspepsia, together with a(More)
BACKGROUND Gastro-esophageal reflux disease (GERD) is a common disease. It impairs health related quality of life (HRQL). However, the impact on utility scores and work productivity in patients with moderate to severe GERD is not well known. METHODS We analyzed data from 217 patients with moderate to severe GERD (mean age 50, SD 13.7) across 17 Canadian(More)
Text recognition in natural scene images is a challenging task that has recently been garnering increased research attention. In this paper, we propose a method for recognizing text by utilizing the layout consistency of a text string. We estimate the layout (four lines of a text string) using initial character extraction and recognition result. On the(More)