Stereo matching cost computation based on nonsubsampled contourlet transform

A new matching cost computation method based on nonsubsampled contourlet transform (NSCT) for stereo image matching is proposed in this paper. Firstly, stereo image is decomposed into high frequency sub-band images at different scales and along different directions by NSCT. Secondly, by utilizing coefficients in high frequency domain and grayscales in RGB color space, the computation model of weighted matching cost between two pixels is designed based on the gestalt laws. Lastly, two types of experiments are carried out with standard stereopairs in the Middlebury benchmark. One of the experiments is to confirm optimum values of NSCT scale and direction parameters, and the other is to compare proposed matching cost with nine known matching costs. Experimental results show that the optimum values of scale and direction parameters are respectively 2 and 3, and the matching accuracy of the proposed matching cost is twice higher than that of traditional NCC cost.     

变换域数字水印处理技术

数字水印是信息安全领域的一项新技术,给出了相对明确的定义。着重分析了变换域数字水印系统的特征及常见攻击,给出了一些相应的对策。最后指出变换域水印的重要问题,即频率的选择问题。     

像增强型夜视系统的图像信息传递

在分析了像增强夜视系统信息传递的基础上，指出像增强器输出端荧光屏至人眼的图像传递过程，构成了像增强夜视系统信息传递量的限制．提出了采用系统信息传递量作为夜视系统设计与评价的方法，利用这种方法可以发现在像增强器增益足以补偿光谱选道衰减的条件下，采用彩色像增强可以大幅度增加夜视系统传输的信息量．     

一种新型彩色三维光学成像系统

提出一种新型三维彩色光学数字成像系统。此系统利用投影结构光对现实世界中的物体进行数字化，同时得到对应的彩色纹理。详细介绍了系统的硬件设计和软件体系结构设计，得到物体彩色纹理的两种不同方法；直接获取和从编码条纹中提取，给出了用该系统得到的实验结果并简单评价了系统的性能。此系统在反求工程、影视制作、三维游戏制作、医学应用等方面有远大的应用前景。     

基于CCD图像的火灾空间定位方法

大空间中火源的空间位置的定位,一直是火灾自动探测与自动扑救中的难点。研究了一种利用单一CCD摄像头进行火灾自动空间定位的方法。根据计算机视觉原理,利用固定在自动消防水炮末端的CCD摄像头随水炮旋转扫描时的角度、位移变化,将CCD摄像头在不同位置所拍摄的图像中火源图像坐标和火源的空间坐标建立联系,从而实现了火源空间位置的自动定位。     

Color Zone Map in Peripheral Vision at Various Illuminance Levels

We measured the entire region of mesopic and photopic vision to determine the color zone covering the visual field with unique red, yellow, green, and blue hue components. Eight kinds of test stimuli in the natural color system (NCS) color notation system were used. These stimuli were presented at horizontal and vertical meridians, and at meridians inclined at 45° angles. The illuminance level was set at six levels: 0.01 lx-1000 lx. The evaluation method measured chromatic, white, and black components as well as the hue component of the stimuli. Results show that the color zone of the retina extended further into the periphery with increasing illuminance; the response of opponent colors y-b was shown to be greater than that of the opponent colors r-g.     

机器人头部的视觉跟踪系统研究

对运动目标进行识别和跟踪是机器人视觉的一项关键技术。提出了一种可以快速跟踪运动目标的系统设计方案,采用了双计算机处理和Memolink通信方式的机器人控制结构,以图像处理为基础,在图像经过校正之后,通过区域分割和目标识别两个步骤来确定目标的位置,并控制机器人对目标进行跟踪。实验表明,该方法具有较高的速度和准确性。     

浅谈防空夜视装备的发展

针对我军现代夜间反空袭作战的制约瓶颈——缺乏夜视装备，提出在预警领域采用被动红外周视扫描系统，在先进的火控领域采用制冷式红外热成像系统．在老式的防空火控系统上利用微光和非制冷红外技术进行改造的方案比较符合我国国情，也是比较现实和可行的。     

丽音（NICAM）双伴音／立体声电视广播技术

本文首先介绍了电视双伴音/立体声广播的几种常用方式,然后着重分析丽音(NICAM)双伴音/立体声广播系统的基本原理,并给出其接收系统的集成电路。