Photoshop的新特色功能介绍之一——全景接片自动合成

这是新版PhotoshopCS的一项新的特色功能,适用于把分别的画面连接起来,合成一幅全景画面,影像质量很好,操作程序简便、快速而实用,本文以实际例子和图像详细阐述其具体操作过程。     

利用鱼眼镜头生成全景图像的方法

介绍了一种利用鱼眼镜头在特殊角度下所拍摄成的图像,以优化的快速展开模型为基础,经过像点坐标变换、双三次插值及内部拼接,生成全景图像的方法。该方法无须运用多幅标准照片拼接,且无须运用柱面模型及成像仪器的参数。最后从MATLAB仿真的实例中验证了此方法的有效性。     

机器视觉中全景图像的非线性测量技术研究

为了扩大观测范围,机器视觉中经常应用全景摄像。本文针对全景图像测量中的非线性问题提出一种解决方案。将一种非线性最小二乘问题的迭代算法应用于非线性图像测量关系函数的构建中,成功解决了全景图像测量中的非线性问题。该方法对于机器人视觉技术以及图像测量技术有一定的参考意义。     

全景照片的拍摄--浅谈回转连续拍摄法的运用

全景照片的拍摄范围广,能够反映出广阔的场景氛围,获得宏大壮观的画面,给人以强烈的视觉冲击效果.全景照片的获得方法主要可以采用全景相机拍摄、回转连续拍照法拍摄、电脑合成制作等多种方法.对于一名普通的拍摄人而言,使用价格昂贵的、对拍摄要求较高的全景相机拍摄全景照片常常是不够现实的;数码照片电脑合成全景照片在综合其设备、制作成本、图像品质等因素来看也不一定能让所有的人所接受.在这种情况下,利用传统拍摄中的回转连续拍照法制作全景照片,无论是从设备、成本、还是从图像品质来看,都不失为一种值得推崇的方法.掌握了回转连续拍摄法,对于利用电脑制作全景照片也有相当大的帮助.     

基于前向映射的全景视觉图像解算方法

解算的主要目的是将全方位图像还原成无畸变的图像.本文根据双曲面折反射全景视觉系统成像特点,提出了一种基于前向映射的全方位图像解算的改进算法.该算法首先采用前向映射空间变换方法将全方位图像的像素映射到虚拟观察平面上,然后利用改进的Shepard散乱数据插值法复原完整的解算图像,从而避免了在畸变的全方位图像中直接插值引起的图像解算的失真.实验结果表明,该方法不但消除了全方位图像的非线性畸变,而且提高了插值精度和图像灰度曲面的光滑性,使解算图像更接近真实景象.     

理光发布小型球面全景相机Theta

理光（Ricoh）今天在IFA上展示了一款相当有趣和具创新意味的数码照相设备。此产品名为Ricoh Theta，理光表示这是全球首款大量生产的能够一次性拍下球面场景影像的设备，也就是说这款相机拍摄的是球形的全景图像。     

理光发布小型球面全景相机Theta

理光（Ricoh）今天在IFA上展示了一款相当有趣和具创新意味的数码照相设备。此产品名为Ricoh Theta，理光表示这是全球首款大量生产的能够一次性拍下球面场景影像的设备．也就是说这款相机拍摄的是球形的全景图像。     

全景图像实时校正系统的设计与实现

利用FPGA作为可见光全景图像处理器,使用硬件畸变校正系统,以达到对全景图像畸变场景的实时校正.全景图像畸变校正核心问题是像素空间位置校正,以CORDIC算法为基础,设计了全景环形图像展开算法,实现了全景环形图像的展开.设计采用ITU-656标准数字视频格式,用VHDL硬件描述语言实现整个校正算法的FPGA设计,试验结果表明,能实现全景环形图像的360.实时展开.     

全景照片和全景照相机

全景照片和全景照相机浙江大学裘然继，冯华君提起全景照相机，人们就会自然联想起别有风味、令人青睐的全景照片。但这是一个笼统概念，细究起来，人们所指的全景照片，还会有许多不同的类型与特色。首先是最近几年才风行起来的全景照片，就是所谓的Ｐａｎｏｒａｍａ摄影...     

话说全景照相机

话说全景照相机张国栋全景摄影已风靡西方世界，在日本和我国台湾省也很流行。前年和去年杭州摄影器材展览会上都展出了我国生产的全景相机，去年７月在北京召开的世界摄影器材展览会上，国外又有新的全景照相机问世。最近不少朋友问我什么是全景摄影和全景相机，在此作一...     

铝镁合金孔蚀形貌图像增强与分割方法研究

对基于图像信息的腐蚀诊断与预测实现过程中腐蚀图像的增强、边缘提取和图像分割的小波分析等技术和算法进行了研究，并以铝镁合金在工业循环水中的孔蚀图像为例，说明了这些方法的应用。结果表明：基于灰度值的图像增强技术可增加腐蚀区域与材料基体的对比，用小波变换可对腐蚀图像进行分解，将腐蚀图像分解为包含主要特征的低频予图像和包含细节特征的高频予图像，相应的小波系数可反映出孔蚀特征，有利于用计算机图像技术实现腐蚀评价和预测。     

红外激励发光材料的图象存储与加减功能

报道了SrS（Eu,Sm）的写入、读出和发射光谱分布及输出发光对输入光强的关系.利用～100μm厚的SrS（Eu,Sm）薄膜进行了图象存储和加减功能的实验,结果表明,该材料在光信息存储和处理中具有很大的应用前景．     

Fusion of MRI and CT images using guided image filter and image statistics

In medical imaging using different modalities such as MRI and CT, complementary information of a targeted organ will be captured. All the necessary information from these two modalities has to be integrated into a single image for better diagnosis and treatment of a patient. Image fusion is a process of combining useful or complementary information from multiple images into a single image. In this article, we present a new weighted average fusion algorithm to fuse MRI and CT images of a brain based on guided image filter and the image statistics. The proposed algorithm is as follows: detail layers are extracted from each source image by using guided image filter. Weights corresponding to each source image are calculated from the detail layers with help of image statistics. Then a weighted average fusion strategy is implemented to integrate source image information into a single image. Fusion performance is assessed both qualitatively and quantitatively. Proposed method is compared with the traditional and recent image fusion methods. Results showed that our algorithm yields superior performance.     

Double Encryption Using Trigonometric Chaotic Map and XOR of an Image

In the most recent decades, a major number of image encryption plans have been proposed. The vast majority of these plans reached a high-security level; however, their moderate speeds because of their complicated processes made them of no use in real-time applications. Inspired by this, we propose another efficient and rapid image encryption plan dependent on the Trigonometric chaotic guide. In contrast to the most of current plans, we utilize this basic map to create just a couple of arbitrary rows and columns. Moreover, to additionally speed up, we raise the processing unit from the pixel level to the row/column level. The security of the new plot is accomplished through a substitution permutation network, where we apply a circular shift of rows and columns to break the solid connection of neighboring pixels. At that point, we join the XOR operation with modulo function to cover the pixels values and forestall any leaking of data. High-security tests and simulation analyses are carried out to exhibit that the scheme is very secure and exceptionally quick for real-time image processing at 80 fps (frames per second).     

基于NSST和SWT的红外与可见光图像融合算法研究

目的鉴于非下采样剪切波变换NSST的红外与可见光图像融合的结果存在细微特征缺失问题,提出一种基于NSST和SWT的红外与可见光图像融合算法,以提升融合图像的质量。方法首先分别对红外与可见光图像进行NSST分解,各得到一个低频系数和多个不同方向、尺度的高频系数。然后低频系数分别通过SWT分解得到新的低频系数和高频系数,通过SWT分解得到的新的低频系数和高频系数分别采用采用线性加权平均法和区域平均能量取大的融合策略,融合结果再进行SWT逆变换得到低频系数融合结果。高频系数采用区域平均能量取大的融合策略进行融合。最后通过NSST逆变换得到最终的融合图像。结果通过仿真实验结果表明,文中算法与NSST,SWT和NSCT等算法相比,融合图像在主观视觉上的红外目标更突出,图像细节更清晰,且在IE, AG, QAB/F, SF和SD等评价指标上也最优。结论文中算法的融合结果能更好地表现源图像的目标信息和细节纹理信息,表明该算法具有优越性。     

论产品形象建构中符号的选择、组织和传播

分析了产品形象的定义及对于企业的价值与意义,认为只有进行产品符号的明确选择、和谐组织与有效传播才能建立产品形象,进而讨论了影响符号选择的几种因素和进行符号组织的两大思路原则。在符号的传播过程中提出了几点策略,使产品形象能避免噪音的干扰并最终得以有效建立。最后指出产品形象只有进行不断的创新和延续才能建立良好且持久的产品形象。     

一种基于正则化和Watson视觉模型的图像指纹算法

大量多媒体应用的发展使得数字图像很容易地被非法操作和篡改,提出一种基于图像正则化和视觉特性的图像指纹算法,可以有效地实现图像的认证和识别.首先对图像进行正则化预处理,消除几何形变对图像的影响,然后对图像进行分块DCT变换,利用Watson视觉模型对DCT系数进行处理,增大人眼敏感的频域系数在计算图像特征时的权重,经过量化形成最终的指纹序列.在图像指纹序列生成过程中,加入密钥控制,提高了指纹的安全性.实验结果表明,该方法的冲突概率在10-7数量级,对JPEG压缩、旋转、缩放等操作具有较好的稳健性.     

Perceptual image hashing using local entropies and DWT

Abstract

Image hashing is an emerging technology in multimedia security. It uses a short string called image hash to represent an input image and finds applications in image authentication, tamper detection, digital watermark, image indexing, content-based image retrieval and image copy detection. This paper presents a hashing algorithm based on the observation that block entropies are approximately linearly changed after content-preserving manipulations. This is done by converting the input image to a fixed size, dividing the normalised image into non-overlapping blocks, extracting entropies of image blocks and applying a single-level 2D discrete wavelet transform to perform feature compression. Correlation coefficient is exploited to evaluate similarity between hashes. Experimental results show that the proposed algorithm is robust against content-preserving operations, such as JPEG compression, watermark embedding, Gamma correction, Gaussian low-pass filtering, adjustments of brightness and contrast, scaling and small angle rotation. Similarity values between hashes of different images are small, indicating good performances in discriminative capability.     

Amplitude, phase, and “coherent” images

A brief analytic survey of studies concerned with the use of complete information about a given object confined in a wave field is given. It is shown that because of the development of modern circuitry, CCD arrays and computers, as well as the phase shifting method, a method that was designed initially for automation of interference measurements, it is now possible to obtain new types of images that are absent in classical optics. __________ Translated from Izmeritel’naya Tekhnika, No. 6, pp. 29–32, June, 2006.     

Low-light-level image enhancement based on fusion and Retinex

Image enhancement, which aims at improving the contrast of low-light-level image and shows the details in the dark, is a widely used technology. When traditional multi-scale retinex (MSR) is used for low-light-level image enhancement, enhancement result will be over-enhanced and the so-called halo will occur. In order to overcome this shortcoming, the result of MSR needs to be further processed. First, MSR result and low-light-level image are fused with weight related to the grey value of the pixels. The result shows that the halo is significantly suppressed, but the brightness of the image is low. Thus, we fuse the image again and take the fusion image which fuses the first step result with the MSR result as the final result. Experimental results show that the proposed algorithm can suppress the halo and preserve the details.