A fourth-order PDE denoising model with an adaptive relaxation method

In this paper, an adaptive relaxation method and a discontinuity treatment of edges are proposed to improve the digital image denoising process by using the fourth-order partial differential equation (known as the YK model) first proposed by You and Kaveh. Since the YK model would generate some speckles into the denoised image, a relaxation method is incorporated into the model to reduce the formation of isolated speckles. An additional improvement is employed to handle the discontinuity on the edges of the image. In order to stop the iteration automatically, a control of the iteration is integrated into the denoising process. Numerical results demonstrate that such modifications not only make the denoised image look more natural, but also achieve a higher value of PSNR

Устранение импульсных помех и флуктуационных шумов в сигнале пирометра на основе метода двумерного сканирования

Запропоновано метод попередньої обробки цифрових даних, отриманих при реєстрації температури біологічного об'єкта пірометром, який дозволяє усунути в корисному сигналі флуктуаційні шуми і імпульсні перешкоди, обумовлені різною регулярною структурою геметріі фотоелектронних елементів оптичної матриці або структурою каналу передачі сигналу.A method is proposed for preliminary processing of digital data obtained by recording the temperature of a biological object with a pyrometer, which allows to eliminate fluctuation noises and impulse noise in a useful signal due to different regular hemetry structures of photoelectronic elements of the optical matrix or the structure of a signal transmission channel.Предложен метод предварительной обработки цифровых данных, полученых при регистрации температуры биологического объекта пирометром, который позволяет устранить в полезном сигнале флуктуационные шумы и импульсные помехи, обусловленные различной регулярной структурой геметрии фотоэлектронных элементов оптической матрицы или структурой канала передачи сигнала

Image Processing Techniques for Assessing Contractility in Isolated Adult Cardiac Myocytes

We describe a computational framework for the comprehensive assessment of contractile responses of enzymatically dissociated adult cardiac myocytes. The proposed methodology comprises the following stages: digital video recording of the contracting cell, edge preserving total variation-based image smoothing, segmentation of the smoothed images, contour extraction from the segmented images, shape representation by Fourier descriptors, and contractility assessment. The different stages are variants of mathematically sound and computationally robust algorithms very well established in the image processing community. The physiologic application of the methodology is evaluated by assessing overall contraction in enzymatically dissociated adult rat cardiocytes. Our results demonstrate the effectiveness of the proposed approach in characterizing the true, two-dimensional, “shortening” in the contraction process of adult cardiocytes. We compare the performance of the proposed method to that of a popular edge detection system in the literature. The proposed method not only provides a more comprehensive assessment of the myocyte contraction process but also can potentially eliminate historical concerns and sources of errors caused by myocyte rotation or translation during contraction. Furthermore, the versatility of the image processing techniques makes the method suitable for determining myocyte shortening in cells that usually bend or move during contraction. The proposed method can be utilized to evaluate changes in contractile behavior resulting from drug intervention, disease modeling, transgeneity, or other common applications to mammalian cardiocytes