【作者】 侯鲜桃；

【导师】 张丽红；

【作者基本信息】 山西大学 ， 物理电子学， 2011， 硕士

【摘要】 图像,作为人类认识世界最主要的工具,其所含的信息内容是非常丰富的,在信息传递的过程中扮演着十分重要的角色。图像的分辨率是衡量图像包含信息多少的重要指标,图像的分辨率越高,代表图像包含的信息也就越多,图像反应的细节也就越丰富,因此在图像的应用领域中,人们都期望获得分辨率较高的图像。然而,由于成像系统本身条件以及外界因素的限制,使得获得的图像的分辨率降低,影响图像在实际中的广泛应用。从硬件方面来说,可以通过减小像素尺寸,增大芯片尺寸或改变探测元排列方式这三种方法来实现对图像分辨率的改善。但是这些方法都受到传感器制造技术和硬件发展水平的限制,很难更进一步提高图像的分辨率。因此,出现了一种利用信号处理技术,从多帧观测到的低分辨率图像得到高分辨率图像的方法,即超分辨率图像重建技术。本文首先对超分辨率图像重建的含义,研究状况及其应用方向进行了简单概述,随后利用数学方法对超分辨率图像重建问题进行了描述和数学建模,并在此基础上对常用的频率域算法和空间域算法进行了分类描述,给出了重建的一般步骤。另外,由于低分辨率图像会受到多种因素的影响而使得有用信息变得比较模糊,所以必须在超分辨率图像重建之前,对低分辨率图像进行预处理(增强,去噪,不良帧的剔除,图像配准等),为后续处理打好基础。其次,在已有运动估计算法的基础上,将块匹配算法与图像多分辨率分解相结合,有效地降低了原有运动估计算法的运算量。并在此基础上提出了一种基于S+P变换和插值处理(文中涉及的插值算法有：最近邻插值、双线型插值和Bezier曲面插值)的超分辨率图像重建算法。最后,通过对本文算法进行实验仿真,结果证明,无论是从主观还是客观方面来说,本文算法都取得了不错的效果。然后通过对整篇文章的系统总结,对超分辨率重建未来的发展方向进行了展望。更多还原

【Abstract】 As the most important learning tool of human, image contains much information and plays a very important role in information transmission. As known, image resolution is an important index which measures how much information the image contains. Higher resolution means more information the image contains, that is to say the detail of the image is much richer. So, everyone wants to obtain the image with high resolution in the region of image processing. However, because of the limits from imaging system and the external factors, the images with low resolution are obtained, which affect the wild use of image.From the view of hardware, we can improve the image resolution by reducing the pixel size, increasing the chip size and changing the arrangement of detection element. Due to the limits of sensor manufacturing technology and hardware development level, it is very hard to further improve the image resolution. Therefore, someone proposed a new method named super resolution image reconstruction technology which would obtain the image with high resolution from the multiple low resolution images using the signal processing technology.In this paper, the concept, research condition and the application of super resolution image reconstruction were introduced simply, and the formation process of image was modeled using the math method firstly. And then, the general steps of reconstruction and the commonly used frequency domain algorithm and special domain algorithm were briefly described. Besides, due to the influence of many factors, low resolution images were blurred and the information of the images was limited. So, it was necessary to do preprocessing before super resolution reconstruction which included enhancement, de-noising, bad frame elimination and image registration, etc. It laid a good foundation for the following processing. Then, according to the existing methods, multi-resolution images registration method based on the block matching was proposed, and then the new super-resolution reconstruction algorithm based on the S + P transformation and interpolation was presented. The nearest neighbor interpolation, bilinear interpolation and Bezier surface interpolation were referred in the paper. Finally, the simulation experiments of the proposed algorithm were done and the results were analyzed using the subjective and objective evaluation indexes. It was proved that the proposed algorithm did well in the experiment. At last, based on the summary of the paper, the future development direction of super-resolution image reconstruction was discussed.更多还原