【作者】 孙平；

【导师】 邹丽新；

【作者基本信息】 苏州大学 ， 检测技术与自动化装置， 2008， 硕士

【摘要】 电子稳像是一种新型的视频图像序列稳定技术,它利用计算机数字图像处理和电子技术相结合的方法来实现图像序列的稳定。由于具有稳像精度高、体积小、功耗低、成本低以及易于操作等优点,电子稳像技术已被广泛用于摄像机抖动的检测和消除,视频压缩,运动目标的检测和跟踪,以及图像拼接等领域。本课题在苏州大学现代光学技术研究所“天巡一号小卫星CCD相机研制”的项目资助下,对电子稳像技术进行了深入研究,有效地实现了视频图像的实时稳定。论文阐述了电子稳像的基本原理、基本方法和处理过程,并讨论了其实现的关键技术。介绍了电子稳像中几种常见的典型算法,同时分析了各算法的优缺点,并针对本课题的要求,分析了实时电子稳像的特点,明确实时稳像算法的要求,最终确定采用基于特征点匹配的电子稳像算法。论文在研究传统的特征点匹配电子稳像算法的基础上,提出了一种改进的特征点匹配算法的电子稳像技术。此方法通过合理的区域划分,进行图像的特征点提取;然后根据特征点集内具有稳定相对位置的结构特征,采用距离不变准则,对特征点的有效性进行验证,保证各点的局部运动具有良好的全局一致性,建立二维运动模型进行全局运动估计;最后利用均值滤波的方法来进行运动补偿,从而实现图像序列的稳定。在进行特征点提取的过程中,课题研究了几种典型的特征点提取算法,并进行实验室仿真和分析,根据本课题要求选取基于Log操作数边缘点提取方法,并采用图像多分辨率分层技术来提高算法的计算速度。此外,论文介绍了电子稳像算法的评价方法。同时还建立电子稳像的软件仿真平台,对基于改进特征点的电子稳像算法进行了稳像处理研究,并利用评价方法对稳像效果进行分析,实验结果表明此算法具有良好的稳像效果。更多还原

【Abstract】 Electronic image stabilization is a new technology to stabilize image sequence, which is combined of computer digital image processing and electronic technology to achieve the stability in the image sequence. It has a lot of advantages, such as high image stabilizing precision, compact size, low power consumption, reasonable price and easy to operate. Therefore it has been widely used in the detection and elimination of video’s dithering, video compression, the moving target detection and tracking, image mosaic, etc. This thesis, supported by the item of the design of CCD camera on the 1st Tianxun Moonlet, has carried out an intensive study of the electronic image stabilization technique, and achieved the effective stabilization of the video image sequence.This thesis expatiates the basic principles, methods and process of the electronic image stabilization, and discusses the key technique of realization. Basing on the study of several typical algorithms for video stabilization and real-time electronic image stabilization algorithm’s requirements, feature points matching algorithm is applied to electronic image stabilization.Basing on the research of the traditional feature points matching algorithm, this thesis presents an improved feature points matching algorithm in electronic image stabilization. Through dividing image into many blocks in reason, the suitable feature points can be selected, which has a stable structure and the relative positions of all points are stable. So the thesis proposes the distance invariant criterion to check the feature matching, which can keep global coherence of all local motions and produce the global motion vector by establishing two-dimensional model of movement. Finally, the average filter is applied to motion compensation to achieve the stability of the image sequence. The thesis also presents several typical feature point extraction algorithms, and has laboratory simulation and analysis. In accordance with the requirements of our item, the method of edge points extraction based on Log operator has been selected, using multi-resolution image layering technology to improve the calculation speed.In addition, the thesis introduces the evaluation methods of image stabilization. And a software simulated platform has been created to analyze and testify the performance of improved feature tracking algorithm. And the results of experiment show that this method has good performances in image stabilization更多还原