Studying pressure sores through illuminant invariant assessment of digital color images

Methods for pressure sore monitoring remain both a clinical and research challenge.Improved methodologies could assist physicians in developing prompt and effective pressure sore interventions.In this paper a technique is introduced for the assessment of pressure sores in guinea pigs,using captured color images.Sores were artificially induced,utilizing a system particularly developed for this purpose.Digital images were obtained from the suspicious region in days 3 and 7 post-pressure sore generation.Different segments of the color images were divided and labeled into three classes,based on their severity status.For quantitative analysis,a color based texture model,which is invariant against monotonic changes in illumination,is proposed.The texture model has been developed based on the local binary pattern operator.Tissue segments were classified,using the texture model and its features as inputs to a combination of neural networks.Our method is capable of discriminating tissue segments in different stages of pressure sore generation,and therefore can be a feasible tool for the early assessment of pressure sores.

Edge Pattern Based Demosaicking Algorithm of Color Filter Array

An efficient adaptive approximation demosaicking algorithm based on the sampled edge pattern was presented for mosaic images from Bayer color filter array. The proposed algorithm determined edge patterns by four nearest green values surrounding the green interpolation location. Then according to the edge patterns, different adaptive interpolation steps were applied. Simulations on 12 Kodak photos and 15 IMAX high-quality images showed that the proposed method outperformed the other four demosaicking methods (bilinear, effective color interpolation, Lu's method and Chen's method) for average color peak signal to noise ratios and maintained a relatively low complexity owing to constant color-difference interpolation step and a reasonable terminating condition of iteration.

Digitally programmable organic light‐emitting tetrodes

Limited to the structure of traditional light‐emitting devices,electronic devices that can directly convert machine language into human visual information without introducing any back‐end circuit are still not easy to achieve.Based on a specially designed three‐phase co‐planar electrode structure,a new type of three‐phase alternating current driven organic light‐emitting device with the integration of emission and control functions,full‐color tunability and simple device structure is demonstrated in this study.We integrate the light‐emitting function of color‐tunable light‐emitting devices and the switching of three triodes in a single three phase organic light‐emitting device.The state control of luminous color and luminance intensity merely requires the introduction of a kind of machine language,that is an easy‐to‐program 6‐bit binary number coded digital signals.The color adjustable area covers 66%of the color triangle of the National Television System Committee.Such simple and easy‐to‐integrate light‐emitting system has great potential applications in the next‐generation man‐machine interface.