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A graph interpretation of the mutual partition distance is presented. Binary integer linear programming formulations for the computation of the measure are provided and the resulting algorithms have shown to be effective when applied to a real-world dataset.

The implementation of fast dedicated processor for block matching motion estimation based on cumulants matching criteria implies the optimization of all of its components. Special care should be spent with the multiply-accumulate unit that is the core of many digital signal processing systems. Therefore, its optimization may be of outmost importance, specially if a significative number of such units are present in the platform. In this paper, the minimization of the size of one such unit is provided for a specific application, although the results have relevance in other scenarios. Index Terms--Cumulants, higher order statistics, multiply-accumulate unit, optimization.

The introduction of a generic framework for segmentation evaluation is discussed. The asymmetric measure is found to stand out in applications insensitive to over segmentations.

A video coding algorithm based on a hybrid DPCM-vector quantization algorithm efficiently compresses test sequences at bit rates between 8 and 16 Kb/s. The algorithm provides good signal-to-noise ratios and subjective quality. The method involves the segmentation of difference images into blocks of variable sizes and shapes, and performs motion compensation and segmentation at the same time. Very active blocks require treatment by the fuzzy classified vector quantizer and large-size blocks are decimated to simplify their vector quantization.

Vector quantization of images raises problems of complexity in codebook search and subjective quality of images. The family of image vector quantization algorithms proposed in this paper addresses both of those problems. The Fuzzy Classified Vector Quantizer (FCVQ) is based on fuzzy set theory and consists basically in a method of extracting a subcodebook from the original codebook, biased by the features of the block to be coded. The incidence of each feature on the blocks is represented by a fuzzy set that captures its (possibly subjective) nature. Unlike the Classified Vector Quantizer (CVQ), in the FCVQ a specific subcodebook is extracted for each block to be coded, allowing a better adaptation to the block. The CVQ may be regarded as a special case of the FCVQ. In order to explore the possible correlation between blocks, an estimator for the degree of incidence of features on the block to be coded is included. The estimate is based on previously coded blocks and is obtained by maximizing a possibility; a distribution that intends to represent the subjective knowledge on the feature's possibility of occurrence conditioned to the coded blocks is used. Some examples of the application of a FCVQ coder to two test images are presented. A slight improvement on the subjective quality of the coded images is obtained, together with a significant reduction on the codebook search complexity and, when applying the estimator, a reduction of the bit rate.

Color and color differences are critical aspects in many image processing and computer vision applications. A paradigmatic example is object segmentation, where color distances can greatly influence the performance of the algorithms. Metrics for color difference have been proposed in the literature, including the definition of standards such as CIEDE2000, which quantifies the change in visual perception of two given colors. This standard has been recommended for industrial computer vision applications, but the benefits of its application have been impaired by the complexity of the formula. This paper proposes a new strategy that improves the usability of the CIEDE2000 metric when a maximum acceptable distance can be imposed. We argue that, for applications where a maximum value, above which colors are considered to be different, can be established, then it is possible to reduce the amount of calculations of the metric, by preemptively analyzing the color features. This methodology encompasses the benefits of the metric while overcoming its computational limitations, thus broadening the range of applications of CIEDE2000 in both the computer vision algorithms and computational resource requirements. [ABSTRACT FROM AUTHOR]

Background: Snoring disorder is a common problem among world population. Treatment modalities may involve surgical and non-surgical procedures. As main objective we proposed to evaluate the efficacy of non-ablative Er:YAG laser in the treatment of snoring disorder., Material and Methods: We performed an interventional study in 30 patients with snoring disorders. Three sessions were performed with Er:YAG laser 2940nm in long pulse mode (2J/cm2) and smooth mode (10-8J/cm2) in oropharynx region. We analyzed the efficacy of this protocol using questionnaires for snoring intensity, snoring related characteristics of quality of life (including the Epworth sleepness scale and OHIP-14), the satisfaction of the patients and existence of adverse effects comparing the results before and after the treatment using Wilcoxon Signed Rank test., Results: There was a 96.7% satisfaction rate after one month of treatment, and 96.4% after 6 months. A reduction of the severity of snoring from 8±1.9 before the treatment to 1.6±1.1 one month after treatment was observed ( p <0.001). Decrease in mean values of Epworth sleepness scale (9.97±5.3 to 6.54±4.3) ( p =0.002), and OHIP-14 score (10.9±6.2 to 5.9±5) ( p <0.001) were also noted. A significant decrease in the Mallampatti and Friedman classification scores were observed ( p =0.001 and p <0.001, respectively). No anesthesia was required, nor adverse effects were observed., Conclusions: Non-ablative Er:YAG laser treatment is a safe, painless, and can be an effective treatment option to reduce snoring and is well accepted by the patient. However, further controlled studies with longer follow-up are required. Key words: Er:YAG laser, snoring, sleep disorders, epworth sleepiness scale, OHIP-14., Competing Interests: Conflicts of interest There are no potential conflicts of interest., (Copyright: © 2020 Medicina Oral S.L.)