Extracting Graphics Information for Better Video Compression

Cloud gaming services are heavily dependent on the efficiency of real‐time video streaming technology owing to the limited bandwidths of wire or wireless networks through which consecutive frame images are delivered to gamers. Video compression algorithms typically take advantage of similarities among video frame images or in a single video frame image. This paper presents a method for computing and extracting both graphics information and an object's boundary from consecutive frame images of a game application. The method will allow video compression algorithms to determine the positions and sizes of similar image blocks, which in turn, will help achieve better video compression ratios. The proposed method can be easily implemented using function call interception, a programmable graphics pipeline, and off‐screen rendering. It is implemented using the most widely used Direct3D API and applied to a well‐known sample application to verify its feasibility and analyze its performance. The proposed method computes various kinds of graphics information with minimal overhead.     

家用摄录机的电子图像稳定系统

本文介绍采用模糊数学控制大规模数字处理电路的电子图像稳定新技术,克服手握一体化摄录机引起的图像晃动效应,以改善图像质量。该技术可广泛应用于视频处理各领域。     

基于FPGA机载实时视频图形处理系统的设计

给出了某机载实时视频图形处理系统的硬件电路设计方案,以XC5VFX70T FPGA作为核心处理器,实现了对DVI及PAL等多种格式视频信号的解码、实时处理以及输出。系统电路设计简洁,具有较强的灵活性和扩展性。文中介绍了系统的硬件整体架构,论证了视频编解码模块和视频缓存模块的硬件设计方案。实际测试结果表明,系统能够流畅地...     

Gray-Scale Image Coding for Freeze-Frame Videoconferencing

A new gray-scale image coding technique has been developed, in which an extended DPCM approach has been combined with entropy coding. This technique has been implemented in a freeze-frame videoconferencing system which is now operational at IBM sites throughout the world. Following image preprocessing, the two fields of the interlaced 512 x 480 pixel video frame are compressed sequentially with different algorithms. The reconstructed image quality is improved by subsequent image postprocessing, the final reconstructed image being almost indistinguishable from the original image. Typical gray-scale video images compress to about a half bit per pixel and transmit over 4.8 kbit/s dial-up telephone lines in about a half minute. The gray-scale image processing and compression algorithms are described in this paper.     

基于TMS320DM6437的4通道视频数据的高速传输

采用TMS320DM6437处理器和TVP5158视频解码器为主器件,在无需外加时序控制下,可实现器件的无缝连接并完成4路视频信号的采集。采集到的4通道模拟信号解码后压缩成1路复合视频数据流并输入到DSP视频前端,DSP处理器需将复合数据流分离成4个单路信号,以供显示图像信息,此过程伴随大量的数据搬移。实验结果表明:通过DSP库函数读取并搬移图像数据速度慢,图像实时性能差;而采用EDMA3传输方式能很好地实现大量视频数据的快速搬移,使得图像实时显示速度可达到23.2 f/s(帧/秒),较传统方法在系统实时性能方面提升了22.5%,从而满足视频信号处理系统的高速实时性要求。     

Un processeur de détection de contours en temps réel dans une image de télévision

Objects identification and localization and more generally scene analysis, need a preliminary step of edge detection. Because of the very important amount of data to be processed, implementing any edge detection algorithm on a conventional computer leads to a high computational cost, too high for many applications: in robotics for instance. The authors present here an on-line real time processor which works upon the digitized signal of a TV camera. This processor computes the two components of the gradient associated with each pixel, using a Sobel operator. Then it selects edge pixels on the basis of informations about the gradient in the neighbourhood of each pixel. The processed image appears synchronously with the video signal, delayed by a 2 TV lines duration compared to the original image.     

监播系统中视频关键帧抽取器的设计与实现

为满足发展迅猛的广电行业对电视频道节目内容的实时监测,提出并设计了一种针对全媒体监播系统的模拟信号关键帧抽取器.该设备采用运行嵌入式Linux系统的ARM处理器S3C2440作为主处理器,同时FPGA芯片EP3C25作为协处理器,极大地提高了设计灵活性和系统的实时处理性能.抽取的视频图像通过视频解码器ADV212压缩后,最终存储到本地SATA硬盘.在验证部分中,闭环测试的试验结果证明了这种设备的正确性和工程实用性.     

A VLSI based MIMD architecture of a multiprocessor system for real-time video processing applications

A MIMD based multiprocessor architecture for real-time video processing applications consisting of identical bus connected processing elements has been developed. Each processing element contains a RISC processor for controlling and data-dependent tasks and a Low Level Coprocessor for fast processing of convolution-type video processing tasks. To achieve efficient parallel processing of video input signals, the architecture supports independent processing of overlapping image segments. Running at a clock rate of 40 MHz, a single processing element provides a peak performance of 640 Mega arithmetic operations per second (MOPS). For the real-time processing of basic video processing tasks like 3×3 FIR-filter, 8×8 2D-DCT and motion estimation, a single processing element provides a sufficient computational rate for video signals with Common Intermediate Format (CIF) at a frame rate up to 30 Hz. For hybrid source coding of CIF video signals at a frame rate of 30 Hz a multiprocessor system consisting of six processing elements is required. A linear speedup of the multiprocessor system compared to a single processing element is achieved. A VLSI implementation of a processing element in 0.8 µm CMOS technology is under development.     

用于视讯解交错的先进影像处理器

本文提出一种用于视讯解交错的先进影像处理器。因为影片模式来源和一般的电视交错影像必须分开处理，因此，采用了一种新颖的使用四个场缓冲器及层次架构的影片来源侦测方法，分离影片及交错的电视影像，以提高侦测正确率。针对电视影像的解交错，提出了一种新颖的、低成本的解交错方法，使用窗口扩展法侦测低角度边缘以去除锯齿，适应三维移动。仿真结果证实，采用该方法可获得极佳的影像画质。     

An image processing system using Image Signal Multiprocessors (ISMPs)

This paper describes an image processing system using Image Signal Multiprocessors (ISMPs) adapted to gray-level image preprocessing for image analysis and image enhancement. It is composed of four ISMPs, five 1H-delay-lines, two 512×512×8-bit frame memories, a video timing controller (VTC), two 256-word ×8-bit ×8-table Look Up Tables (LUTs) and 80 nsec/sampling A/D and D/A converters. This multiprocessor system performs convolution operations such as spatial filters, contrast enhancement, and binarization for gray-level images, thinning, thickening, pattern matching etc. for binary images, and image quality improvement for moving images such as T.V. images. Otherwise, it performs feature extraction operations such as area calculations, fillet coordination, and moment calculations for objective image data. Moreover, this system is capable of applying color image processing by using a multiboard system.     

一种快速且准确的噪声估计算法

噪声估计是视频和图像处理最重要的环节之一,实际应用中要求算法能够快速且准确地估计噪声。提出了一种基于块的快速且可靠的噪声估计算法,其中噪声假设为加性零均值高斯白噪声。此算法需要一个N1×N1的窗口,及相应的方差求值运算,避免了排序,复杂度由排序过程的o（n2）或者o（nlog2 n）降为o（n）。此算法中的主要参数会根据图像或者视频信息进行自适应调整,从而提高算法的准确性。通过实验发现,此算法是快速且准确的。     

视频图像压缩在物联网监测系统中的应用

在物联网监测系统中,由于视频图像所占空间较大,且所需的通信带宽要求高,会在传输和存储的过程中造成困难,因此需要对视频图像进行压缩。文中介绍了一种适用于物联网监测系统的视频图像压缩方法,即通过帧预测、DCT变换和可变长编码相结合的方式对视频图像进行编码和相应的解码。经过实验表明,该方法有效地压缩了视频图像,且在提高视频图像传输速率的同时,减少了传输时间。     

Digital Video: A Buffer-Controlled Dither Processor for Animated Images

A new technique has been discovered which permits pseudo-gray tone video images to be played in real-time on bilevel, memory displays such as the ac plasma panel. The technique combines ordered dither processing, selective updating, and hysteretic thresholding to digitally transmit or store the video images. Only a 1 bit/pel frame memory plus a 0.3 bits/pel replenishment buffer are required. This technique makes possible the use of a single terminal to display both graphic-alphanumeric information as well as pseudo-gray tone video images.     

Development of an optical triplicator for intravital videomicroscopy of oxygen saturation

The Optical Triplicator produces three copies of a portion of a microscopic image and places them side-by-side on the face of a video image tube, so that all three images can be viewed simultaneously in each video frame. The Optical Triplicator was used in an intravital microscopy assembly to obtain simultaneous images of a microvessel at three visible wavelengths selected to enable the accurate determination of oxygen saturation in microvessels of the hamster retractor muscle. An image processing system was used to obtain light intensity and optical density from video recordings made using the triplicator. Lumenal oxygen saturation profiles were determined using the measured intensity values and a published three wavelength photometric method     

Virtual Museum-3-D fine art appreciation system

We have developed an interactive multimedia system for the appreciation of three-dimensional art objects, such as porcelain and sculptures. With the system, the viewer is able to see a representation of the object from various directions as if holding it in his/her hands. He/she can enjoy the object images on high-quality HDTV (Hi-Vision) display, with supplementary audio and written information about the object. This system consists of (1) a video server, to store the HDTV images of the fine arts, which have been shot from various paths around the fine arts at 0.2 degree intervals; (2) a specially designed manipulator to select a desired image from the server; and (3) an HDTV or stereoscopic HDTV display, and accompanying spectacles. The HDTV video server can randomly access data at a video rate (1/60 sec), so as to quickly respond to the operations of the manipulator. The experimental system has been tested by many artists and scientists for operability and effectiveness, and has been confirmed as useful for art galleries and other educational institutions     

基于DaVinci的自动对焦算法研究及实现

随着信息技术、超大规模集成电路技术、微电子技术的进一步发展,特别是高性能微处理器的使用,数字视频技术得以飞速发展。视频系统的基本功能是为了获取清晰图像,而自动对焦技术对图像质量影响很大。该文对自动对焦算法的关键技术进行研究,提出了改进的自动对焦算法。搭建了基于达芬奇（DaVinci）DM6437处理器的硬件平台,并在该平台上实现了自动对焦。从对焦速度来看,完成一次对焦约需0．65S,基本达到了系统的设计要求。     

A Video Codec Transmitter

The transmitter of a video codec system is designed and realized in ECL hardware. This video codec system is capable of carrying one commercial NTSC color television channel with a program audio channel at a rate of 42.9 Mb/s. The transmitter interfaces with a DPCM processor. The transmitter removes the horizontal blanking interval from the composite television signal, converts the quantized difference signal from the DPCM processor into 4/8-bit dual length code and buffers the codes for constant rate transmission. A line synchronization code is multiplexed with audio and video codes to form a serial data link at 42.9 Mb/s. This can be transmitted on a T3 (44.7 Mb/s) digital carrier. The transmitter is composed of four functional units: controller, coder, buffer and multiplexer. This paper describes the design, layout, testing and evaluation of the high speed digital system that results in 2 to 1 data compression of the digital video.     

基于改进SIFT算法对录制视频的质量评估

文章通过选取30个涵盖人物、风景、设备等不同场景下的短视频,在电视卖场选取9个不同电视机品牌并采用Iphone、VIVO、HUAWEI三种不同拍摄设备对30个短视频进行录制;针对录制视频时出现的位移、形变等问题,采用结合边缘检测及改进SIFT算法的录制视频处理办法,首先使用边缘检测算法寻找播放设备框界,通过逐帧操作实现录制视频空间一致性;然后利用图像特征匹配算法中的尺度不变特征变换匹配视频开始和结束画面,去除时域上产生的冗余;利用录制视频的边缘线性,采用映射边缘检测算法,同时针对视频处理耗时过长的问题,使用曼哈顿距离计算参考图与待匹配图的相似度降低算法复杂度。最后将处理后的录制视频去和原始视频得到空间和时间上的对齐,然后采用SSIM进行质量评估。     

A single-chip optical sensor with analog memory for motiondetection

A 64×64-pixel image sensor with full-frame analog memory and on-chip motion processor is presented. The processor consists of a charge amplifier and an analog subtractor. It uses the switched-capacitor technique and calculates the difference between the values of the signal on each pixel in successive frames. The rate can achieve up to 60 frames/s with limited area and power overhead. The analog memory required for the storage of the previous frame is implemented using implanted capacitors placed within the sensor array. Fabricated in a 1.2-μm standard CMOS process with an added metal 3 light-shielding layer, the circuit is fully functional and requires a total core area of 13 mm²     

基于FPGA的实时视频图像几何校正系统设计

基于后向映射查找表结构的几何校正算法的研究,针对双线性插值算法的特殊性,提出了四邻域像素的图像存储和插值方法,实现了图像插值时对静态存储器SRAM的快速随机读写。根据该方法设计的基于FPGA的实时视频图像几何校正系统的视频延时小于一帧,只需要改变视频图像的后向映射查找表,就可实现不同映射的视频图像几何校正。