共查询到20条相似文献,搜索用时 15 毫秒
1.
图像拼接在基于图像的绘制、视频检索以及景物匹配等领域有着广泛的应用,为了获取大画面宽视场的场景表示,针对存在旋转及缩放变化的图像,提出了一种基于对数极坐标映射的图像拼接方法,该方法先将图像从笛卡儿坐标空间转换到对数极坐标空间,使得笛卡儿坐标空间中图像的旋转和缩放转换为对数极坐标空间中图像的二维平移,这样可直接利用相位相关法来估算出图像间的旋转角度和缩放因子,然后以此作为初值,再采用非线性最小化优化算法进一步求精图像间的运动参数来实现图像的配准,最后通过图像融合来实现图像的拼接。实验结果表明,该方法是有效的。 相似文献
2.
3.
Minimal Aspect Distortion (MAD) Mosaicing of Long Scenes 总被引:2,自引:0,他引:2
Alex Rav-Acha Giora Engel Shmuel Peleg 《International Journal of Computer Vision》2008,78(2-3):187-206
Long scenes can be imaged by mosaicing multiple images from cameras scanning the scene. We address the case of a video camera
scanning a scene while moving in a long path, e.g. scanning a city street from a driving car, or scanning a terrain from a
low flying aircraft.
A robust approach to this task is presented, which is applied successfully to sequences having thousands of frames even when
using a hand-held camera. Examples are given on a few challenging sequences. The proposed system consists of two components:
(i) Motion and depth computation. (ii) Mosaic rendering.
In the first part a “direct” method is presented for computing motion and dense depth. Robustness of motion computation has
been increased by limiting the motion model for the scanning camera. An iterative graph-cuts approach, with planar labels
and a flexible similarity measure, allows the computation of a dense depth for the entire sequence.
In the second part a new minimal aspect distortion (MAD) mosaicing uses depth to minimize the geometrical distortions of long
panoramic images. In addition to MAD mosaicing, interactive visualization using X-Slits is also demonstrated.
This research was supported by the Israel Science Foundation. Video examples and high resolution images can be viewed in . 相似文献
4.
随着数字化信息技术的不断发展,监视系统已经成为各行业领域中的重要应用.随着WiFi等无线技术的发展,实现了视频数据的无线传输,因其特有的便捷性将传统的有线监视系统取而代之.图像拼接是目前图像处理的一项热门技术,将两幅或者多幅具有重叠区域的图像拼接成一幅无缝隙高分辨率的图像.本论文结合WiFi无线技术和图像拼接技术的优势,提出了基于WiFi的分布式监视场景拼接系统,多个客户端采集的图像通过WiFi无线网络传输到服务器,服务器对传输过来的图像采用SIFT算法和RANSAC算法完成拼接,最终实现了宽场景监视.实验结果表明该系统可以有效地实现监视场景拼接. 相似文献
5.
Stitching motions in multiple videos into a single video scene is a challenging task in current video fusion and mosaicing research and film production. In this paper, we present a novel method of video motion stitching based on the similarities of trajectory and position of foreground objects. First, multiple video sequences are registered in a common reference frame, whereby we estimate the static and dynamic backgrounds, with the former responsible for distinguishing the foreground from the background and the static region from the dynamic region, and the latter functioning in mosaicing the warped input video sequences into a panoramic video. Accordingly, the motion similarity is calculated by reference to trajectory and position similarity, whereby the corresponding motion parts are extracted from multiple video sequences. Finally, using the corresponding motion parts, the foregrounds of different videos and dynamic backgrounds are fused into a single video scene through Poisson editing, with the motions involved being stitched together. Our major contributions are a framework of multiple video mosaicing based on motion similarity and a method of calculating motion similarity from the trajectory similarity and the position similarity. Experiments on everyday videos show that the agreement of trajectory and position similarities with the real motion similarity plays a decisive role in determining whether two motions can be stitched. We acquire satisfactory results for motion stitching and video mosaicing. 相似文献
6.
为了获取宽视野的场景表示,提出了一种基于块匹配的视频图像镶嵌算法,该算法首先采用基于相位相关的块匹配方法估计出视频图像间的运动矢量场,并剔除其中由于图像噪声或运动物体的遮挡而导致外点运动矢量,然后根据图像的运动矢量场确定出图像子块之间的对应点对,进而利用得到的对应点对迭代求解图像间的变换模型参数以实现视频图像的自动镶嵌.针对真实场景的视频图像序列进行实验,获得了较好的镶嵌结果,表明了该算法的有效性. 相似文献
7.
为了解决大场景全景图拼接过程中的误差累积问题,提高图像拼接的一致性,提出了一个新的全景图拼接算法。把全局图像配准看作是一个统计估计问题,运用增广的卡尔曼滤波对图像的全局变换参数进行递归地增广和估计。实验结果表明,得到的变换参数是全局一致的,生成的全景图不存在拼接裂缝。拼接算法考虑了各种不确定性,适用于噪声大场景的全景图拼接。 相似文献
8.
《Robotics and Autonomous Systems》2014,62(12):1755-1767
We present a new image mosaicing technique that uses sequential aerial images captured from a camera and is capable of creating consistent large scale mosaics in real-time. To find the alignment of every new image, we use all the available images in the mosaic that have intersection with the new image instead of using only the previous one. To detect image intersections in an efficient manner, we utilize ‘Separating Axis Theorem’, a geometric tool from computer graphics which is used for collision detection. Moreover, after a certain number of images are added to the mosaic, a novel affine refinement procedure is carried out to increase global consistency. Finally, gain compensation and multi-band blending are optionally used as offline steps to compensate for photometric defects and seams caused by misregistrations. Proposed approach is tested on some public datasets and it is compared with two state-of-the-art algorithms. Results are promising and show the potential of our algorithm in various practical scenarios. 相似文献
9.
为了对大规模显微图像进行高质量的拼接,首先提出拼接图的概念及获得高质量全景图像的3个原则,然后采用分块-空间聚类算法配准相邻图像,同时评估配准质量,并计算拼接图的边的权值;最后在此基础上,提出了一种基于最小路由代价生成树的图像拼接方法,该方法通过计算拼接图的最小路由代价生成树来确定所有图像的全局位置,并用来生成全景图像。实验结果表明,该方法可获得高质量的全景图像。 相似文献
10.
We present an approach that significantly enhances the capabilities of traditional image mosaicking. The key observation is that as a camera moves, it senses each scene point multiple times. We rigidly attach to the camera an optical filter with spatially varying properties, so that multiple measurements are obtained for each scene point under different optical settings. Fusing the data captured in the multiple images yields an image mosaic that includes additional information about the scene. We refer to this approach as generalized mosaicing. In this paper we show that this approach can significantly extend the optical dynamic range of any given imaging system by exploiting vignetting effects. We derive the optimal vignetting configuration and implement it using an external filter with spatially varying transmittance. We also derive efficient scene sampling conditions as well as ways to self calibrate the vignetting effects. Maximum likelihood is used for image registration and fusion. In an experiment we mounted such a filter on a standard 8-bit video camera, to obtain an image panorama with dynamic range comparable to imaging with a 16-bit camera. 相似文献
11.
研究了相机存在绕光轴转动的情况下柱面全景图的生成,首先对柱面图像进行傅立叶变换,根据图像的傅立叶谱来估算出图像间的初始平移和旋转运动参数,再利用Levenberg-Marquardt非线性最小化方法逐步求精各运动参数,最后根据计算出的运动参数进行图像拼合获得柱面全景视图,实验结果表明该算法可以获得比较理想的拼接效果. 相似文献
12.
《Image and vision computing》2002,20(9-10):751-759
We describe the construction of accurate panoramic mosaics from multiple images taken with a rotating camera, or alternatively of a planar scene. The novelty of the approach lies in (i) the transfer of photogrammetric bundle adjustment techniques to mosaicing; (ii) a new representation of image line measurements enabling the use of lines in camera self-calibration, including computation of the radial and other non-linear distortion; and (iii) the application of the variable state dimension filter to obtain efficient sequential updates of the mosaic as each image is added.We demonstrate that our method achieves better results than the alternative approach of optimising over pairs of images. 相似文献
13.
图像镶嵌技术是近年来发展迅速的图像处理技术之一,是计算机视觉领域和计算机图形学领域都十分关注的研究热点之一。通过对现有遥感图像镶嵌方法的研究,时其进行了归纳和总结,并介绍了几种常见的图像镶嵌关键技术。 相似文献
14.
In this paper we propose an accurate and robust image mosaicing method of soccer video taken from a rotating and zooming camera
using line tracking and self-calibration. The mosaicing of soccer videos is not easy, because their playing fields are low
textured and moving players are included in the fields. Our approach is to track line features on the playing fields. The
line features are detected and tracked using a self-calibration technique for a rotating and zooming camera. To track line
features efficiently, we propose a new line tracking algorithm, called camera parameter guided line tracking, which works even when the camera motion undergoes sudden changes. Since we do not need to know any model for scenes beforehand,
the proposed algorithm can be easily extended to other video sources, as well as other sports videos. Experimental results
show the accuracy and robustness of the algorithm. An application of mosaicing is also presented. 相似文献
15.
16.
Mohamed Koubaa Maher Elarbi Chokri Ben Amar Henri Nicolas 《Multimedia Tools and Applications》2012,56(2):281-301
We present in this article a new video watermarking which resists collusion, MPEG4 compression and frame dropping attacks.
This scheme is based on video mosaicing. For that, we are going to start by describing the mosaicing technique in order to
illustrate the contribution of this technique in video watermarking. In fact, mosaicing allows to select an interesting area
where the mark should be embedded. The idea is to insert the same mark into the same pixels which represent the same physical
point. This is exactly the information which can be provided by a mosaic image at least for the located points in the scene
background. Next, we present extensive experimental simulations which prove the watermark imperceptibility and robustness
against several video attacks. 相似文献
17.
Manifold mosaicing is arguably the most important class of image mosaicing methods. The existing manifold mosaicing methods work reasonably well only for scenes with simple plane structure and for images taken in a usual way such that the camera??s motion direction is perpendicular to its optical axis. A novel manifold modeling theoretical framework is presented to unify the current image mosaicing methods. Based on this framework, an effective mosaicing algorithm is also proposed to mosaic tubular scenes which have failed most existing methods. We adopt a two-step shaping strategy to parallelize the optical flows and change the topological genus of the image strips by M?bius mappings and circular ring extending. We performed computational experiments via image sequences acquired from tubular scenes and obtained excellent panoramas. The theoretical framework and algorithms in this paper have immediate applications to many practical tubular scene mosaicing problems in medical imaging, industrial inspection, gaming, virtual reality and robotics. 相似文献
18.
This paper describes an approach to the acquisition and representation of information on 3D painted surfaces (usually frescoes) based on the tassellation and mosaicing of the whole surface. The acquisition is carried out using an active vision system specifically designed for these purposes. In this paper, particular emphasis is placed on the mosaicing procedure of the acquired images, which, while conceptually simple, allows one to obtain very good results thanks to the effective exploitation of the features of the acquisition system. A careful qualitative and quantitative analysis of the performances of the system, obtained through tests on real scenes in the laboratory, is also presented.Received: 28 May 2001, Accepted: 8 November 2002, Published online: 18 June 2003
Correspondence to: Paolo GrattoniMassimiliano Spertino: With I.R.I.T.I. under grant N.202.12484 of the Italian Safeguard of Cultural Heritage C.N.R. project. 相似文献
19.
三维破碎物体多尺度拼接技术 总被引:2,自引:0,他引:2
在分析三维物体碎片轮廓曲线的特征和表示的基础上,研究多尺度小波轮廓描述符的计算,提出了一种多尺度下轮廓曲线特征提取及基于多尺度分析的三维物体碎片拼接方法.轮廓曲线经多尺度小波变换平滑后,提取曲率和挠率构成特征矢量;在选择了基于小波轮廓描述符的三维曲线匹配起点后,比较2条轮廓曲线的特征矢量以判断轮廓的相似性,并将轮廓匹配的2块相邻物体碎片拼接,实现破碎物体复原.最后通过实验验证了该方法的有效性. 相似文献
20.
航空图像的镶嵌在图像情报分析中有着重要的军事意义,通过分析机载航空光学成像的特点及平台参数,结合光学成像的透视投影模型,推导出倾斜投影下从像素坐标到世界坐标的统一坐标变换关系,并在世界坐标下计算图像的大致镶嵌区域,实现图像粗镶嵌;再提取粗镶嵌区域中的SIFT特征,计算镶嵌图像之间的变换模型参数,实现图像精确镶嵌。实验结果表明,算法在运算速度和镶嵌精度上取得了较好的效果。 相似文献