Fu Y.,Sharp Laboratories of America |
Jacques S.L.,Oregon Health And Science University
Progress in Biomedical Optics and Imaging - Proceedings of SPIE | Year: 2011
Monte Carlo (MC) simulation was implemented in a three dimensional tooth model to simulate the light propagation in the tooth for antibiotic photodynamic therapy and other laser therapy. The goal of this research is to estimate the light energy deposition in the target region of tooth with given light source information, tooth optical properties and tooth structure. Two use cases were presented to demonstrate the practical application of this model. One case was comparing the isotropic point source and narrow beam dosage distribution and the other case was comparing different incident points for the same light source. This model will help the doctor for PDT design in the tooth. © 2011 SPIE.
Sullivan G.J.,Microsoft |
Boyce J.M.,Vidyo Inc. |
Chen Y.,Qualcomm |
Ohm J.-R.,RWTH Aachen |
And 2 more authors.
IEEE Journal on Selected Topics in Signal Processing | Year: 2013
This paper describes extensions to the High Efficiency Video Coding (HEVC) standard that are active areas of current development in the relevant international standardization committees. While the first version of HEVC is sufficient to cover a wide range of applications, needs for enhancing the standard in several ways have been identified, including work on range extensions for color format and bit depth enhancement, embedded-bitstream scalability, and 3D video. The standardization of extensions in each of these areas will be completed in 2014, and further work is also planned. The design for these extensions represents the latest state of the art for video coding and its applications. © 2007-2012 IEEE.
Rodriguez-Pardo C.E.,University of Rochester |
Sharma G.,University of Rochester |
Feng X.-F.,Sharp Laboratories of America
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2014
Traditional methodologies for primary selection usually consider the optimization of parameters that characterize the global performance of the display system, such as the luminance of the white point, gamut volume, and power consumption. We propose a methodology for primary design that optimizes a figure of merit designed to favor gamuts for which maximum luminance at each chromaticity is uniformly related to the corresponding maximum luminance over the set of optimal colors. We contrast the results obtained with the proposed methodology with those obtained by an alternative strategy based on the optimization of gamut volume, and analyze differences in performance between these approaches for both three and four primary systems. Results indicate that the global vs local design choices result in significantly different primary designs. © 2014 SPIE-IS&T.
Deshpande S.,Sharp Laboratories of America
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2013
Adaptive media playout techniques are used to avoid buffer underflow in a dynamic streaming environment where the available bandwidth may be fluctuating. In this paper we report human perceptions from audio quality studies that we performed on speech and music samples for adaptive audio playout. Test methods based on ITU-R BS. 1534-1 recommendation were used. Studies were conducted for both slow playout and fast playout. Two scales-a coarse scale and a finer scale was used for the slow and fast audio playout factors. Results from our study can be used to determine acceptable slow and fast playout factors for speech and music content. An adaptive media playout algorithm could use knowledge of these upper and lower bounds on playback speeds to decide its adaptive playback schedule. © 2013 SPIE-IS&T.
Aghagolzadeh M.,Michigan State University |
Segall A.,Sharp Laboratories of America
ICASSP, IEEE International Conference on Acoustics, Speech and Signal Processing - Proceedings | Year: 2013
In this paper, we consider the problem of removing jaggy artifacts from images. We consider the kernel regression framework and propose a reduced-rank quadratic adaptive method that adapts to the local gradient direction. The proposed technique is effective in shrinking isophote fluctuations, and the result is smooth edges. We observe that it is critical to differentiate jaggy artifacts from texture, junctions and corners, so that meaningful image structure is preserved. Here, we demonstrate that the spectrum of the local covariance matrix of gradients, also known as the structure tensor, is well suited for differentiation of jaggy artifacts from image structure, and we incorporate this into the kernel regression framework. Results show the efficacy of the approach. Namely, that the method is effective in reducing jaggy artifacts without blurring meaningful image structure. © 2013 IEEE.
Xu X.,Sharp Laboratories of America |
Kerofsky L.,Sharp Laboratories of America
Journal of the Society for Information Display | Year: 2011
Nowadays, low-contrast viewing of LC displays (LCDs) occurs very often, which includes the viewing of mobile LCDs at high ambient illumination and the viewing of LCDs at low-power mode. These cases result in low-content visibility and low contrast, leading to an unpleasant viewing experience. In this paper, a technique to improve the perceived contrast and visibility of images at lowcontrast viewing conditions is proposed. The proposed approach enhances image brightness with content and ambient adaptive image brightening and highlights visual parts and boundaries with nonphotorealistic rendering. The proposed technique enables longer battery life for mobile LC devices and makes mobile LC devices viewable at high ambient illumination. It also enables TVs with extreme low-power consumption and smart-grid responsive TVs. © 2011 Society for Information Display.
Kerofsky L.,Sharp Laboratories of America |
Segall A.,Sharp Laboratories of America |
Kim S.-H.,Sharp Laboratories of America
Data Compression Conference Proceedings | Year: 2013
This paper describes a scalable extension of the High Efficiency Video Coding (HEVC) standard that supports different color gamuts in an enhancement and base layer. Here, the emphasis is on scenarios with BT.2020 color gamut in an enhancement layer and BT.709 color gamut in the base layer. This is motivated by a need to provide content for both high definition and ultra-high definition devices in the near future. The paper describes a method for predicting the enhancement layer samples from a decoded base layer using a series of multiplies and adds to account for both color gamut and bitdepth changes. Results show an improvement in coding efficiency between 65% and 84% for luma (57% and 85% for chroma) compared to simulcast in quality (SNR) scalable coding. © 2013 IEEE.
Deshpande S.,Sharp Laboratories of America
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2012
Perceived video quality studies were performed on a number of key classes of noise removal algorithms to determine viewer preference. The noise removal algorithm classes represent increase in complexity from linear filter to nonlinear filter to adaptive filter to spatio-temporal filter. The subjective results quantify the perceived quality improvements that can be obtained with increasing complexity. The specific algorithm classes tested include: linear spatial one channel filter, nonlinear spatial two-channel filter, adaptive nonlinear spatial filter, multi-frame spatio-temporal adaptive filter. All algorithms were applied on full HD (1080P) content. Our subjective results show that spatio-temporal (multi-frame) noise removal algorithm performs best amongst the various algorithm classes. The spatio-temporal algorithm improvement compared to original video sequences is statistically significant. On the average, noise-removed video sequences are preferred over original (noisy) video sequences. The Adaptive bilateral and non-adaptive bilateral two channel noise removal algorithms perform similarly on the average thus suggesting that a non-adaptive parameter tuned algorithm may be adequate. © 2012 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).
Deshpande S.,Sharp Laboratories of America
Proceedings - 2013 IEEE International Symposium on Multimedia, ISM 2013 | Year: 2013
The newly approved High Efficiency Video Coding Standard (HEVC) includes temporal sub-layering feature which provides temporal scalability. Two types of pictures-Temporal Sub-layer Access Pictures and Step-wise Temporal Sub-layer Access Pictures are provided for this purpose. This paper utilizes the temporal scalability of HEVC to provide bandwidth adaptive HTTP streaming to clients. We describe our HTTP streaming algorithm, which is media timeline aware. Temporal sub-layers are switched on the server side dynamically. We performed subjective tests to determine user perception regarding acceptable frame rates when using temporal scalability of HEVC. These results are used to control the algorithm's temporal switching behavior to provide a good quality of experience to the user. We applied Internet and 3GPP error-delay patterns to validate the performance of our algorithm. © 2013 IEEE.
Hoshino K.,Sharp Laboratories of America |
Yeh B.,Oregon State University |
Wager J.F.,Oregon State University
Journal of the Society for Information Display | Year: 2013
An indium-gallium-zinc oxide or a zinc-tin oxide thin-film transistor (TFT) fabricated when the relative humidity in the laboratory is less than 50% is found to exhibit good electrical performance, with an abrupt, distortion-free transfer curve and a turn-on voltage close to 0 V. In contrast, when such an amorphous oxide semiconductor (AOS) TFT is fabricated at a relative humidity greater than 50%, its "as-fabricated" electrical performance is very poor, typically characterized by a large amount of hysteresis, a strongly negative turn-on voltage, and a kink-like distortion in the subthreshold region of its transfer curve. However, the electrical performance of such a poor-quality TFT is observed to improve over time, if it is simply stored in the dark at room temperature without being subjected to electrical stress. This recovery usually requires weeks (months) for an unpassivated (passivated) AOS TFT. Recovery is tentatively ascribed to the gradual removal of moisture from the AOS TFT channel layer. © Copyright 2013 Society for Information Display.