• Journal of Korean Ophthalmic Optics Society
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• v.14 no.3
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• pp.37-42
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• 2009

Purpose: There is uncertainty if the vergence facility would provide clinically significant supplementary information to the fusional vergence measurements. The purpose of this study was to determine the relationship between vergence facility and fusional vergence in a group of symptomatic subjects. Methods: A total of 114 symptomatic subjects aged 9 to 13 years, who passed the vision screening test, participated in this study. Vergence facility was measured with 8$\Delta$ BI/8$\Delta$ BO flipper lenses and a suppression control target, the 20/30 letter line on Vectogram 9 (Bernell, USA). Near fusional vergence was measured with a single 20/30 vertical line target by Von Graefe technique. In order to avoid excessive convergence stimulation, negative fusional vergence (NFV) range (blur, break and recovery) was measured followed by positive fusional vergence (PFV) ranges (blur, break and recovery). Results: Pearson correlations were calculated and showed no correlations between vergence facility and any of fusional vergence measurements (p>0.05). Also, there were no significant differences of vergence facility measurements on the compensating vergence that passed or failed Sheard and Morgan's criterion for comfortable vision (p>0.05). Conclusions: There was no correlation between vergence facility and fusional vergence among symptomatic subjects. Hence, both vergence facility and fusional vergence should be assessed for those with binocular dysfunction in order to make an accurate diagnosis and management plan.

• Journal of Korean Ophthalmic Optics Society
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• v.16 no.2
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• pp.171-177
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• 2011

Purpose: The purpose of this study was to investigate the relationships between reading ability and binocular functions, based on self tests through surveys. The possibility of the reading ability tests used in this study as a tool on the determination about vision efficiency was also evaluated. Methods: Through reading ability tests about 138 university students, 72 students (52.2%) of them were first selected. Through self tests about dyslexia and light sensitivity, 38 students (52.7%) of the first selected students were secondly selected, whose extents are more than 3. Binocular tests were carried out about three groups (high, middle, low) of these secondly selected students. Tests about NPCs, distance and near phoria, amplitude of accommodation, fusional vergence, AC/A ratio, accommodative facility, and vergence facility were performed as binocular tests. Results: NPCs were closest to eyes at high groups. Fusional vergence, AC/A ratio, accommodative facility, and vergence facility of high group showed higher than other groups. The phoria at middle group showed higher than other groups. Conclusions: We found that reading ability and some of binocular functions were closely related. Therefore, vision training, associated with insufficiencies of binocular functions, is expected to improve reading ability.

• Journal of Broadcast Engineering
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• v.16 no.6
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• pp.1018-1025
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• 2011

Scalable Video Coding (SVC) extension of H.264/AVC is a new video coding standard for media convergence by providing diverse videos of different spatial-temporal-quality layers with a single bitstream. Recently, real-time SVC codecs are being developed for the application areas of surveillance video and mobile video, etc. This paper presents the design and implementation of a H.264/SVC decoder based on an embedded DSP using Open SVC Decoder (OSD) which is a real-time software decoder designed for the PC environment. The implementation consists of porting C code of the OSD software from PC to DSP environment, profiling the complexity performance of OSD with further optimization, and integrating the optimized decoder into the TI Davinci EVM (Evaluation Module). 50 QCIF/CIF frames or 15 SD frames per second can be decoded with the implemented DSP-based SVC decoder.