Gaussian filtering for FPGA based image processing with High-Level Synthesis tools

With the gradual improvement and uprising interest from the industry to High-Level Synthesis tools, like Vivado HLS form Xilinx, Field Programmable Gate Arrays are becoming an attractive option for accelerator architecture in image processing domain. However, an efficient high-level design still requires knowledge of hardware specifics. A great amount of image processing operations falls into a group of convolution-based operators - operators which result depends only on a particular pixel and its neighborhood and obtained by performing a convolution between a kernel and a part of an image. This paper investigates the impact of factors, such as kernel size, target frequency, convolution implementation specifics, floating-point vs. fixed-point filter kernel, on resulting register-transfer level design of convolution-based operators and FPGA resources utilization. The Gaussian filter was analyzed as an example of a convolution-based operator. It is shown experimentally that floating-point operators require a noticeably larger amount of resources, rather fixed-point once. Resulting clock frequency independence from kernel size is demonstrated as well as the number of used flip-flops grows with the increasing target clock frequency is investigated in this work.Although using of HLS can simplify and accelerates the development of FPGA-based applications, it is still requires careful design space exploration. It is crucial to remember that existing HLS tools do not provide full abstraction and the result of the development is not software but hardware. The efficiency of resulting FPGA solution and its resources utilization depends heavily on many factors which have to be taken into account on the programming stage. Floating-point operations implemented on FPGA are usually inefficient and consume a tremendous amount of resources, therefore should be avoided. Kernel size doesn’t affect clock frequency and just increases the number of resources required for storing bigger kernel and temporary image areas. A number of used flip-flops grows rapidly with the increasing target clock frequency and generally bigger for bigger kernels. Therefore a trade-off between target speed and resources utilization should be considered by a developer. A benefit achieved with the use of vendor-provided libraries has to be noted. They provide convenient abstractions usually at no additional resources cost. Thus, for instance, window and line buffers from Vivado Video Library might be used as an alternative to hand-programmed data structures. Results obtained in this work might be extended to any convolution-based image processing operator implemented on FPGA with HLS

Two calibration models for compensation of the individual elements properties of self-emitting displays

In this paper, we examine the applicability limits of different methods of compensation of the individual properties of self-emitting displays with significant non-uniformity of chromaticity and maximum brightness. The aim of the compensation is to minimize the perceived image non-uniformity. Compensation of the displayed image non-uniformity is based on minimizing the perceived distance between the target (ideally displayed) and the simulated image displayed by the calibrated screen. The S-CIELAB model of the human visual system properties is used to estimate the perceived distance between two images. In this work, we compare the efficiency of the channel-wise and linear (with channel mixing) compensation models depending on the models of variation in the characteristics of display elements (subpixels). It was found that even for a display with uniform chromatic subpixels characteristics, the linear model with channel mixing is superior in terms of compensation accuracy.This work was supported by Russian Science Foundation (Project No. 20-61-47089)

First experimental results obtained using the highpower free electron laser at the siberian center for photochemical research

The first lasing near the wavelength of 140 µm was achieved in April 2003 using a high-power free electron laser (FEL) constructed at the Siberian Center for Photochemical Research. In this paper we briefly describe the design of the FEL driven by an accelerator–recuperator. Characteristics of the electron beam and terahertz laser radiation, obtained in the first experiments, are also presented in the paper.У Сибірському центрі фотохімічних досліджень навесні 2003 року отримана генерація випромінювання з довжиною хвилі 140 мкм на потужному лазері на вільних електронах (ЛВЕ). У роботі коротко описана конструкція ЛВЕ на базі прискорювача рекуператора і представлені результати вимірювання деяких параметрів електронного пучка і терагерцового випромінювання.В Сибирском центре фотохимических исследований весной 2003 года получена генерация излучения с длиной волны 140 мкм на мощном лазере на свободных электронах (ЛСЭ). В работе кратко описана конструкция ЛСЭ на базе ускорителя рекуператора и представлены результаты измерения некоторых параметров электронного пучка и терагерцового излучения

Digital literacy and digital didactics for the development of new learning models

© 2020, Universidad del Zulia. All rights reserved. The study aims to investigate digital literacy and digital didactics as the basis for the development of new learning models via comparative qualitative research methods. As a result, the principle of personalization implies the ability of a student to independently determine the purpose of training, choose a strategy for the educational process, the pace and level of development of the educational program. In conclusion, to determine digital literacy, an index was developed which shows how prepared the teacher is for learning online and through innovation

Obstacle Detection Quality as Problem-Oriented Approach to Stereo Vision Algorithms Estimation in Road Situation Analysis

Основная статьяВ данной работе рассматривается метод оценки качества алгоритмов детектирования препятствий на основе стереозрения, учитывающий особенности задачи распознавания дорожной ситуации, с малой трудоёмкостью подготовки тестовых данных. Описываемый подход был разработан для применения в автономных системах анализа дорожной ситуации, таких как беспилотные наземные транспортные средства или системы помощи водителю, и может также применяться для построения проблемноориентированных критериев оценки качества алгоритмов стереореконструкции. In this work we present a method for performance evaluation of stereo vision based obstacle detection techniques that takes into account the specifics of road situation analysis to minimize the effort required to prepare a test dataset. This approach has been designed to be implemented in systems such as selfdriving cars or driver assistance and can also be also used as problem-oriented quality criteria for stereo vision algorithms

Bioengineered Bile Duct: the project resume and state of the art in 2018

Aim. Development of the physiologically relevant tissue-engineered graft for repair of bile duct injures (Dyuzheva et al., 2016). <br><br>Conclusions. Designed scaffold showed no cytotoxicity, both BM-MSCs and cholangiocytes migrated into the depth of fibrous material. The constructs was biodegradable in various model mediums: deionized water, phosphate buffer, bile, full culture medium. The next step is pre-clinical trials on rabbits and minipigs for assessment of implantation safety and efficacy. We suppose that this tubular multilayered tissue-engineered construct will be capable to integration in native tissues after implantation and may be used to injured bile duct reparation