An image-recognition system using algorithmically dedicated integrated circuits

An image-recognition system was implemented with a set of eight algorithmically dedicated integrated circuits to recognize two-dimensional objects that are characterized by their closed outer contours. The complete system operates at rates up to 15 frames/second using a standard workstation as a controller. The recognition system achieved a 97% recognition rate for over 10,000 trials of recognition of eight objects over a wide range of orientation and size variations. A 100% recognition rate was achieved if size variations were eliminated. The set of 4-micron NMOS image processor chips operates on 10-megahertz 8-bit video data (512 × 512 images) in real time. The processors include: a 3 × 3 linear convolver, a 3 × 3 sorting filter, a 7 × 7 logical convolver, a contour tracer, a feature extractor, a look-up table ROM, and two post-processors for the linear convolver. Each chip was designed using an architecture that is dedicated to the particular image processing task being performed. The design time for all of the chips was kept to 1.5 man-years by developing a set of design guidelines. The relationship between the algorithms that were implemented and the silicon implementation is discussed.     

User interface for video observation over the internet

This paper presents the design and application of a system for live video transmission and remote camera control over the World Wide Web. Extensive testing of the Internet Video Server (IVS) prompted us to improve its user interface. The GlobalView extension of IVS was developed which enables the generation of panoramic images of the environment and a more intuitive control of the camera. The live video frame is superimposed on a 360^°static panoramic picture. By interactively moving a rectangular frame in the panoramic picture, the user locally selects the new direction of the camera. Once the view is selected the users prompts the selection and the command is issued over the Internet to the remotely-controlled camera. The static panoramic image is constantly updated in areas where new live video information gets available. Two methods are described for static panoramic image generation: one uses geometric transformation and the other is the brute-force scanning approach. We discuss how visual summaries of activities on an observed location can be generated and custom queries made with a similar intuitive user interface.     

Sketching MLS Image Deformations On the GPU

In this paper, we present an image editing tool that allows the user to deform images using a sketch‐based interface. The user simply sketches a set of source curves in the input image, and also some target curves that the source curves should be deformed to. Then the moving least squares (MLS) deformation technique [ [SMW06] ] is adapted to produce realistic deformations while satisfying the curves' positional constraints. We also propose a scheme to reduce image fold‐overs in MLS deformations. Our system has a very intuitive user interface, generates physically plausible deformations, and can be easily implemented on the GPU for real‐time performance.     

Efficient Implementation of Image Warping on a Multimedia Processor

The spatial transformation of images, commonly known as image warping, is fundamental to many applications, e.g. remote sensing, medical imaging, computer vision, and computer graphics. Computational demands in image warping are high, requiring a geometric transformation, address and coefficient generation, and some form of interpolation. However, unlike most image processing algorithms, the data flow for image warping can be highly irregular, which makes any efficient implementation challenging.This paper describes an efficient algorithm which addresses these challenges by making use of the capabilities of a single-chip multiprocessing microprocessor, the Texas Instruments TMS320C80 MVP (multimedia video processor). the MVP's advanced digital signal processors (ADSPs) offer tremendous computational power through instruction-level parallelism and several key features designed for image processing. The MVP's intelligent input/output interface via the transfer controller (TC) permits efficient irregular memory accesses.Affine and perspective warps have been implemented for 8-bit, 16-bit and and RGB color data using bilinear interpolation.The affine warp can generate 512 × 512 warped output images faster than real-time video rates require. For 8-bit images, the performance is 14.1 ms. Although the amount of computation necessary is the same for 16-bit images, the execution time increases to 15.2 ms since twice as many bytes need to be transferred. For RGB color images, it takes 28.0 ms. The perspective warp requires 46.3 ms for 8-bit and 16-bit images, and 60.4 ms for RGB color images. This unprecedented performance for software-based image warping exceeds many hardware approaches reported in the literature.     

USB接口的MPEG视频卡的改进

文章对一种USB接口的MPEG视频卡进行了改进与扩容,使其成为能多路同时采集射频信号和视频信号的USB接口视频卡。测试表明，改进后该卡工作稳定，图像效果较好。     

Fast GPU-based denoising filter using isoline levels

In this study, we describe a GPU-based filter for image denoising, whose principle rests on Matheron’s level sets theory first introduced in 1975 but rarely implemented because of its high computation cost. We use the fact that, within a natural image, significant contours of objects coincide with parts of the image level-lines. The presented algorithm assumes an a priori knowledge of the corrupting noise type and uses the polygonal level-line modeling constraint to estimate the gray-level of each pixel of the denoised image by local maximum likelihood optimization. Over the 512 × 512 pixel test images, the freely available implementation of the state-of-the-art BM3D algorithm achieves 9.56 dB and 36 % of mean improvement in 4.3 s, respectively, for peak signal to noise ratio and mean structural similarity index. Over the same images, our implementation features a high quality/runtime ratio, with a mean improvement of 7.14 dB and 30 % in 9 ms, which is 470 times as fast and potentially allows processing high-definition video images at 19 fps.     

基于伪随机序列的视频图像加密新算法

分析了视频序列的I，P帧传输特性，并针对该特性以及实时系统的延迟要求，提出了一种新的加密算法。在变换域中对直流分量引入基于伪随机序列的伪随机噪声，使其白化。该算法充分利用直流系数的方块效应，大大减少了计算量；同时，由于只改变直流系数，从统计特性上看，不会增加码率，这对系统的信道要求非常有利。最后，对整个加密、解密过程进行分析，对比其结果和信噪比。实验结果表明，该算法能有效地防止数据被窃取，并且不会使视频失真。     

基于 DirectShow的通用多路视频接口研究和实现

本文在多路视频监控系统背景下,主要研究和实现了基于DirectShow架构且能响应视频区域鼠标消息的通用多路视频接口,并成功地把该接口应用于该多路系统中。本文设计 的接口,不需要考虑视频捕获硬件的差异,可同时处理多路视频（播放、暂停、捕获和视频区域任意切分）,并接受用户直接在视频区域的鼠标操作,灵活控制各路视频。该
该接口提供一个函数和二个类,以MFC扩展DLL的形式封装。     

基于CDMA1X网络的视频传输系统设计与软件实现

设计开发了一种基于CDMA1X无线网络的视频传输系统.介绍了基于CDMA1X无线网络和因特网的视频无线网络传输系统组成结构,利用微软的视频软件开发工具包VFW,完成了系统应用软件设计.为了改善视频图像实时传输效果,深入研究了5种流量监控手段和传输控制策略.实践证明,在CDMA1X低带宽网络条件下,本系统可以实现较为流畅的实时视频图像传输并具有一定的实时性.     

应用于图象融合的高集成度视频信号采集系统

为配合多波段图象实时融合系统的研制，设计和开发了高速、高集成度，并具有广泛通用性的前端视频信号采集系统。该系统的设计和开发采用了专用视频解码芯片和大规模可编程逻辑器件（EPLD）以及VHDL语言。系统具有集成度高、可靠性好、性能优良、体积小、接口简单、采样参数在线可编程修改等特点。其应用于多波段图象采集和融合系统中，作为前端图象采集部分取得了良好的效果。同时，该设计也可作为前端图象采集部分用于其他图象处理系统中。     

An ASIC implementation of Kohonen's map based colour image compression

This paper presents a new hardware design for a neural network based colour image compression. The compressed image consists of a colour palette containing few best colours and the coded image. Kohonen's map neural network is applied to construct the colour palette and the coded image, both forming the compressed image. The Kohonen's map based compression results in linear time complexity (in the size of the image). It is advantageous over traditional JPEG in colour quantization applications and compression of images with limited colours. The architecture of the hardware unit is based on single instruction multiple data methodology. The architecture has been implemented in an application specific integrated circuit and results show that the proposed design achieves high speed allowing inputs at a video rate for compression of images up to size of 512×512 with low area requirement.     

Data generation and representation method for 3D video conferencing using programming by demonstration

Video conferencing provides an environment for multiple users linked on a network to have meetings. Since a large quantity of audio and video data are transferred to multiple users in real time, research into reducing the quantity of data to be transferred has been drawing attention. Such methods extract and transfer only the features of a user from video data and then reconstruct a video conference using virtual humans. The disadvantage of such an approach is that only the positions and features of hands and heads are extracted and reconstructed, whilst the other virtual body parts do not follow the user. In order to enable a virtual human to accurately mimic the entire body of the user in a 3D virtual conference, we examined what features should be extracted to express a user more clearly and how they can be reproduced by a virtual human. This 3D video conferencing estimates the user’s pose by comparing predefined images with a photographed user’s image and generates a virtual human that takes the estimated pose. However, this requires predefining a diverse set of images for pose estimation and, moreover, it is difficult to define behaviors that can express poses correctly. This paper proposes a framework to automatically generate the pose-images used to estimate a user’s pose and the behaviors required to present a user using a virtual human in a 3D video conference. The method for applying this framework to a 3D video conference on the basis of the automatically generated data is also described. In the experiment, the framework proposed in this paper was implemented in a mobile device. The generation process of poses and behaviors of virtual human was verified. Finally, by applying programming by demonstration, we developed a system that can automatically collect the various data necessary for a video conference directly without any prior knowledge of the video conference system.     

Practical mini-PACS based on a hybrid video and digital network.

The Department of Radiology of the Shinshu University Hospital is presently in the process of developing a new type of mini-PACS with a hybrid architecture consisting of a video and a digital image archiving network. The video block consists of a server station with a video write-once optical disk (LD) and three workstations which are connected to two ultrasound imaging devices and an MRI device. The video images from any of these imaging devices are transferred immediately onto an LD. The examiner can observe the archived images immediately without any interruption of the examination. The image transmission time, including the record and play-back, is within 3 s. The digital block consists of a personal computer server and various workstations linked to the ETHERNET. This digital system supports database management, and archives digital images. This prototype system was used for daily clinical examinations from February 1989 to January 1990 and 31,366 images from 1561 patients were stored on the video disk. This one year experience suggests that a hybrid mini-PACS system is practical for total image archiving when the image matrix is less than 512 x 512 and selected digital image archiving.     

基于TIC6的视频通信系统

首先简要介绍Tms320c6201芯片结构,然后重点介绍了编解码端系统设计,包括编解码核心模块、视频采集与显示设计以及通信接口。对针对硬件特点和应用要求的软件设计考虑也作了简要的介绍。该系统能够在Tms320c6201上实现512512黑白图像信号的实时编解码,恢复图像质量良好。     

Design and performance of a pixel-level pipelined-parallel architecture for high speed wavelet-based image compression

Wavelets have widely been used in many signal and image processing applications. In this paper, a new serial-parallel architecture for wavelet-based image compression is introduced. It is based on a 4-tap wavelet transform, which is realised using some FIFO memory modules implementing a pixel-level pipeline architecture to compress and decompress images. The real filter calculation over 4 × 4 window blocks is done using a tree of carry save adders to ensure the high speed processing required for many applications. The details of implementing both compressor and decompressor sub-systems are given. The primarily analysis reveals that the proposed architecture, implemented using current VLSI technologies, can process a video stream in real time.     

基于VfW的实时视频图像采集处理程序设计

鉴于实时视频图像采集处理技术在安全监控、视频会议、网络聊天等领域正得到越来越广泛的运用,文中介绍如何利用VideoforWindows库函数来构建视频图像的采集框架;由于回调函数是各种型号视频采集卡处理视频图像的通用接口,分析了如何自定义回调函数来实时处理采集的视频数据,并利用梯度差分法来实时检测视频图像的活动轮廓,该方法可运用于视频目标监控、人脸检测等视频图像处理项目。     

Multi-Modal Human Interactions with an Intelligent Interface Utilizing Images, Sounds, and Force Feedback

One goal of research in the area of human–machine interaction is to improve the ways a human user interacts with a computer through a multimedia interface. This interaction comprises of not only text, graphical animation, stereo sounds, and live video images, but also force and haptic feedback, which can provide more “real” feeling to the user. The force feedback joystick, a human interface device is an input–output device. It not only tracks user's physical manipulation input, but also provides realistic physical sensations of force coordinated with system output. As part of our research, we have developed a multimedia computer game that assimilates images, sounds, and force feedback. We focused on the issues of how to combine these media to allow the user feel the compliance, damping, and vibration effects through the force feedback joystick. We conducted series of human subject experiments that incorporated different combinations of media, including the comparative study of the different performances of 60 human users, aiming to answer the question: What are the effects of force feedback (and associated time delays) when used in combination with visual and auditory information as part of a multi-modal interface? It is hoped that these results can be utilized in the design of enhanced multimedia systems that incorporate force feedback.     

非接触式浮体六自由度监测系统研究

提出了一种非接触式浮体六自由度运动测量与分析系统。该系统由视频采集模块、三维计算模块、用户交互模块3 部分构成。视频采集模块用来获取不同视角的图像信息;三维计算模块融合了改进的摄像机自标定技术、立体视觉特征点检测技术、六分量解算方法等,目的是求得物体6 个自由度的运动情况;用户交互模块提供了定点可视的物体姿态及角度变化信息,方便用户进行分析计算。实测证明,该测量系统设备简单,重构速度快,能适应复杂的海上环境并能够实现远距离监测,满足浮体测量使用要求。     

基于颜色和变形模板的实时人体检测

针对目前人体检测算法存在不能检测多角度人体目标以及实时性差等问题,提出了一种在静态图像中实时检测任意角度人体目标的算法。该算法分别利用目标颜色和轮廓两类特征构造两种检测器。颜色检测器首先进行基于面部肤色和头部发色的彩色分割,然后引入积分图像算法快速提取分割后的图像头部目标区域。轮廓检测器利用头肩轮廓形状的稳健性,用参数化变形模板对头肩轮廓建模,该模板由两个存在几何尺度和位置约束的椭圆构成,再定义两个不同计算复杂度的模板匹配策略对人体头肩部分进行分级检测。最后利用上述两种检测器构建一个级联检测系统,级联检测结构大大提高了算法的速度,使算法可以对分辨率为352×288的图像做30 fps的实时检测,实验结果表明,该算法是切实有效的。     

User models of subjective image quality assessment on virtual viewpoint in free-viewpoint video system

In this paper, we present a user model of subjective quality assessment on virtual viewpoint image (VVI) for free-viewpoint video system. VVIs are rendered through neighbor viewpoint color and depth images, and it is a new type of image that generated for human-computer interaction (HCI) in free-viewpoint video system. In this system, a natural scene is captured by multi-viewpoint cameras, and users can view the scene from any desired viewpoint, regardless the real or virtual one. The subjective quality of VVIs is crucial for the quality of experiences for HCI, because the magnitude of VVI is much greater than the real. In order to find the user model of VVI quality assessment, we organize three sets of stimuli, including Symmetric Stimuli, Asymmetric Stimuli Part I and Part II, to reveal the psychological responses of participants. A psychometric function is consequently obtained to determine the relationship between stimulus and psychological responses. Further discussions on the factors of distortion level, gender, age and academic background are examined to find the influence on the user model. We find that the distortion level of neighbor viewpoint color images has the dominant impact on the user model, while other factors contribute little.