一种CCD彩色摄像系统的视频锁相同步系统

介绍一种应用于ＣＣＤ彩色摄像系统的视频锁相同步系统。基于锁相理论的视频锁相同步系统是一个二级锁相环路,包括同步信号发生电路和高频点像素时钟电路。并详细阐述了同步信号发生电路和高频点像素时钟电路的锁相原理及电路。高频点像 时钟电路的外分频电路是由现场可编门阵列实例可编程特必珂得到不同频率的高频点像素时钟。     

Research on high-speed TDICCD remote sensing camera video signal processing

Video signal processing needs high signal-to-noise ratio (SNR) in high-speed time delay and integration charge coupled devices (TDICCD). To solve this problem, this article first analyzes the characteristics of the output video signal of a new type of high-speed TDICCD and its operation principle. Then it studies the correlation double sample (CDS) method of reducing noise. Following that a synthesized processing method is proposed, including correlation double sample, programmable gain control, line calibration and digital offset control, etc. Among the methods, XRD98L59 is a video signal processor for the charge coupled device (CCD). Application of this processor to one kind of high-speed TDICCD with eight output ports achieves perfect video images. The experiment result indicates that the SNR of the images reaches about 50 riB. The video signal processing for high-speed multi-channel TDICCD is implemented, which meets the required project index.     

一种CCD相机的视频处理电路设计与噪声分析

为使CCD相机系统能够捕获到高信噪比的图像,介绍了一种视频处理器TDA9965的应用电路设计,简述了其内部组成框图及工作原理。利用某型号TDI CCD作为系统传感器,成功实现了对CCD输出模拟视频信号的量化处理,能够使相机系统完成实时采集图像等任务。同时分析了视频处理器电路设计对相机系统图像信噪比的影响,以电源噪声为干扰源,具体计算了在电路设计不合理和改进设计后两种情况下,CCD相机图像信噪比的变化,并通过试验测试验证,合理的电路设计可以使图像的信噪比提高20 dB以上,从而说明了视频处理电路合理设计的重要性,为高速高信噪比CCD相机的研制提供了技术基础。     

高速采集图像实时压缩算法

为了解决高速图像采集给图像数据的实时传输和存储带来的困难,提出了一种基于提升形态Haar小波的面向自动目标识别(ATR)的图像压缩算法——目标形态小波图像编码(TMWC).该算法将形态Haar小波与数学形态学方法结合应用.首先将采集图像进行二维提升形态Haar小波分解,结合目标感兴趣区域(ROI)检测要求的特点,仅在尺...     

运用Cadence软件实现高速图像处理电路设计

随着半导体工艺的迅猛发展,器件的上升沿越来越短,而总线越来越宽,高速设计仿真和分析需要贯穿产品的整个设计过程,高速电路设计成为我们在设计电路时必须要解决的问题.而高速设计所面临的信号完整性问题(包括信号过冲和下冲、信号振铃回绕、信号延迟、信号串扰、接地反弹等),成为利用传统设计方法进行设计的一个瓶颈.     

Single-chip color camera using a frame-transfer CCD

The feasibility of a color-encoding scheme based upon a symmetric shift pattern with a frame-transfer CCD has been demonstrated. The color mosaic filters were fabricated by etching uniform filter blanks, and single-chip color imagers were produced by applying these filters to commercially available b/w CCD's. Two different demultiplexing schemes were evaluated experimentally, and a prototype camera with excellent low-light-level performance was demonstrated; for surveillance and consumer applications, usable pictures with good color separation were obtained at light levels below 3 lx.     

Real-time multimedia processing in video sensor networks

Video sensor networks (VSNs) has become the recent research focus due to the rich information it provides to address various data-hungry applications. However, VSN implementations face stringent constraints of limited communication bandwidth, processing capability, and power supply. In-network processing has been proposed as efficient means to address these problems. The key component of in-network processing, task mapping and scheduling problem, is investigated in this paper. Although task mapping and scheduling in wired networks of processors has been extensively studied, their application to VSNs remains largely unexplored. Existing algorithms cannot be directly implemented in VSNs due to limited resource availability and shared wireless communication medium. In this work, an application-independent task mapping and scheduling solution in multi-hop VSNs is presented that provides real-time guarantees to process video feeds. The processed data is smaller in volume which further releases the burden on the end-to-end communication. Using a novel multi-hop channel model and a communication scheduling algorithm, computation tasks and associated communication events are scheduled simultaneously with a dynamic critical-path scheduling algorithm. Dynamic voltage scaling (DVS) mechanism is implemented to further optimize energy consumption. According to the simulation results, the proposed solution outperforms existing mechanisms in terms of guaranteeing application deadlines with minimum energy consumption.     

传输型CCD相机成像分辨率自动测试研究

对CCD相机成像分辨率自动测试方法进行了研究,测试方案中改进设计了照相分辨率靶标,开展了数据分析处理,通过软硬件结合实现了对CCD相机整机分辨率的自动测试,结果数据经过专业测试比对确认有效。实验结果表明,方法客观、准确,能够避免以往人工测试分辨率带来的主观因素影响,具有很高的实用性。     

实时CCD成像跟踪处理系统研究

提出了基于高速数字信号处理器TMS320C6415的图像识别跟踪系统，并给出了成像跟踪系统的原理图和结构图。重点论述了采集系统和图像处理系统。在软件上采用矩不变阈值分割和基于梯度的自适应阂值分割提取目标，采用投影特征的质心跟踪算法及基于线性微分拟合的记忆外推跟踪技术跟踪目标。实验结果表明：该系统跟踪稳定可靠，完全满足实时性要求。     

传输型CCD相机综合像质评价方法的研究

介绍了以CCD探测器为图像栽体的CCD相机整机系统的综合像质评价方法.通过成像理论建模,分别对光学系统、CCD器件及相机整机系统进行调制传递函数分析.利用CCD器件的"离散采样"特性不满足线性空间不变性的条件,确定调制传递函数的使用限制条件.给出了CCD相机整机系统的调制传递函数测试方案和测试条件,完成了实验室整系统"调制传递函数"的检测试验,并对检测结果进行分析与评价,实现了CCD相机整机系统的像质评价.     

A high-speed digital filter LSI for video signal processing

A ninth-order symmetrical filter has been developed for use in two-dimensional (2-D) processing in TV video systems, especially in high-definition TV receivers. A 2-D filter that is composed of only two types of LSIs (one-dimensional (1-D) digital filter LSI and delay-line) is discussed. The architecture of the digital filter LSI and circuit techniques are presented to obtain high-speed operation, to save chip area, and to decrease power consumption. The order and the transfer function of the filter can be altered by means of the external terminals. The chip, achieved through 2-/spl mu/m CMOS technology, contains about 52000 transistors and occupies an area of 50 mm/SUP 2/. It operates at a high clock frequency of over 33 MHz, and dissipates only 600 mW of power.     

摆扫式面阵CCD航空相机的像旋转分析

航空相机在进行拍照时,通常采用45°扫描反射镜绕光轴摆扫或步进,进行多行迹摆扫式拍照,以增大对地面景物的观测范围,但当扫描镜绕光轴旋转对物体进行观测时,物体反射像也将绕轴进行旋转,目标相对探测器(CCD)产生了像旋转。通过运用光线矢量与光轴旋转变换的方法,建立了相机的数学模型。根据该模型,针对扫描反射镜旋转所产生的像旋转,利用光学矩阵建立了扫描镜转角与像旋转角之间的关系,对比各种消除像旋方法的优缺点,提出了采用扫描镜与像面旋转机构同步旋转结合的方法实现消除像旋,为工程设计提供了必要参考。     

CCD遥感相机视频电子系统FPGA软件集成化设计

为满足CCD遥感相机视频电子系统集成化、小型化的需求,提出一种FPGA软件集成化设计方法,将传统视频电子系统中焦平面软件、信号处理软件和积分时间软件三部分软件集成在一片FPGA中。通过软件模块标准化使软件结构更加优化,可靠性更高。实际应用表明,该软件集成化设计能够实现焦平面软件、信号处理软件和积分时间软件的全部功能,简化了硬件电路的同时提高了软件集成度,具有很高的工程应用价值。     

基于DSP的CCD天文图像处理系统

介绍了一个基于DSP的CCD天文图像处理系统的软硬件实现。分析对比了传统的基于PC机的处理方法,提出了一种简化的背景估计方法,并在此基础上应用了按列扫描的目标提取方法。给出了一种对局部背景进行精确估计的方法,保证了星象中心和星等的计算精度。最后给出了系统的硬件结构以及DSP软件算法的流程。     

基于DSP的嵌入式CCD天文图像处理系统

基于CCD的天文图像采集与处理系统是空间目标光电探测的主要手段之一.分析了现有CCD天文图像采集与处理系统的不足,并据此设计出了适合于嵌入式应用的CCD天文图像处理系统.试验结果表明该处理系统能够在一定程度上提高CCD天文图像处理系统的处理能力.     

基于DSP视频图像采集处理系统设计

随着实时图像采集处理要求的不断提高和大规模集成电路的迅速发展,传统的图像采集系统速度慢、处理功能简单、采用分立元件、电路非常复杂;而且可靠性差、不易调试、不能很好地满足特殊要求.本文从目前国内外图像现状分析出发,设计了一种改进型的视频图像采集处理系统,给出了系统的硬件电路设计及软件流程设计,经仿真测试满足系统指标要求.     

A single-board video codec using video image signal processors

This paper discusses a newly developed single-board video codec using Video Image Signal Processors (VISPs). The codec has both a CCITT H.261 mode and a proprietary mode. Two VISPs, one for encoding and one for decoding, are used. The board size is 210 by 295 mm, the maximum frame rate is about 7.5 f/s, and the picture size is 180 by 144 pels.     

电子荧光内窥镜实时图像处理系统

文中根据内窥镜肿瘤手术的发展趋势,设计一套电子荧光内窥镜实时图像处理系统。该系统采用OV5640图像传感器采集病灶图像,光纤导光的LED作为其功率可控的光源。根据光源开关状态区分暗亮场,开关频率与摄像头的帧率一致。通过计算摄像头与拍摄物体距离,迭代其曝光时间及焦距,从而使图像获得合适的亮度及清晰度。FPGA将接收的图像存储在DDR2中。通过缓存控制及合成算法得到病变与正常组织差异性较高的图像,将其以一定的帧数组合,使用VGA线缆输出至显示器。与传统的内窥镜系统相比,其主要侧重于图像采集与光源的同步,自动调节曝光时间,使得手术医生能够方便地提取出不同光照度下图像的差异信息。     

Real-time image processing approach to measure traffic queueparameters

The real-time measurement of various traffic parameters including queue parameters is required in many traffic situations such as accident and congestion monitoring and adjusting the timings of the traffic lights. In case of the queue detection, at least two algorithms have been proposed by previous researchers. Those algorithms are used for queue detection and are unable to measure queue parameters. The authors propose a method based on applying the combination of noise insensitive and simple algorithms on a number of sub-profiles (a one-pixel-wide key-region) along the road. The proposed queue detection algorithm consists of motion detection and vehicle detection operations, both based on extracting edges of the scene, to reduce the effects of variation of lighting conditions. To reduce the computation time, the motion detection operation continuously operates on all the sub-profiles, but the vehicle detection is only applied to the tail of the queue. The proposed algorithms have been implemented on an 80386-based microcomputer system and the whole system works in real-time     

Study of solder jet bumping process using high-speed digital camera

With the development of solder jet technology in the electronic packaging industry, the bumping process of a molten metal droplet, which determines the shape of the solder bump and is crucial for the performance of the device, has attracted great interests. The solder bumping process of a single molten micro-droplet by a solder jet was recorded using a high-speed digital camera with a frame rate of 100,000 frames per second. It was found that the surface ripples on the solder bump was caused by the interaction of the fluid flow and the heat transfer/solidification processes in the bumping process of a micro-droplet. A droplet was observed to rebound on a copper pad coated with a layer of organic solderability preservatives, which was suspected to decrease the interfacial heat transfer coefficient between the droplet and the pad lower than a minimal value, 4.07×10⁴ W/m² K, making the recoiling droplet rebound away.