Nanofibres have been widely used in many chemical engineering applications and their performance greatly depends on the size distribution of the nanofibres. Researchers have developed automated tools to determine nano...
详细信息
Nanofibres have been widely used in many chemical engineering applications and their performance greatly depends on the size distribution of the nanofibres. Researchers have developed automated tools to determine nanofibre diameters, primarily using commercial MATLAB software package. However, no researchers have reported automatic processing of multiple images, which is essential to the consistency and accuracy of results. Nor has anyone reported nanofibre sizing using deep learning. Therefore, this paper reports an automated tool to measure the size distribution of electrospun nanofibres by simultaneous multi-image processing. This tool determines the diameters of nanofibres using deep learning based on UNet model. Results show that the UNet-based deep learning approach is more accurate than those obtained using existing methods, compared to experimental data.
Sparse modeling can be used to characterize outlier type noise. Thanks to sparse recovery theory, it was shown that 1-norm super-resolution is robust to outliers if enough images are captured. Moreover, sparse modelin...
详细信息
Sparse modeling can be used to characterize outlier type noise. Thanks to sparse recovery theory, it was shown that 1-norm super-resolution is robust to outliers if enough images are captured. Moreover, sparse modeling of signals is a way to overcome ill-posedness of under-determined problems. This naturally leads to this question: does an added sparsity assumption on the signal improve the robustness to outliers of the 1-norm super-resolution, and if yes, how strong should this assumption be? In this article, we review and extend results of the literature to the robustness to outliers of overdetermined signal recovery problems under sparse regularization, with a convex variational formulation. We then apply them to general random matrices, and show how the regularization parameter acts on the robustness to outliers. Finally, we show that in the case of multi-image processing, the structure of the support of signal and noise must be studied precisely. We show that the sparsity assumption improves robustness if outliers do not overlap with signal jumps, and determine how the regularization parameter can be chosen.
This paper describes a simple and fast algorithm for removing occlusions that may occur in multiple views of a scene. In contrast to many methods of the literature, no assumption is made on occlusion shapes, colors or...
详细信息
ISBN:
(纸本)9781479970612
This paper describes a simple and fast algorithm for removing occlusions that may occur in multiple views of a scene. In contrast to many methods of the literature, no assumption is made on occlusion shapes, colors or motions. Instead, this new method assumes that the background can be re-warped using an homography and that the reflectivity is quasi-Lambertian. After geometric and photometric alignments, three methods are evaluated. A median based method, a novel algorithm based on maximal clique detection and a robust PCA method are compared on real and simulated image sequences. This comparison shows that the new clique-based method provides the best performance in terms of quality and reliability.
This paper addresses the problem of obtaining a quality photograph of a painting by multi-image fusion methods. The problem is particularly challenging because of the uncontrolled illumination conditions and of the de...
详细信息
This paper addresses the problem of obtaining a quality photograph of a painting by multi-image fusion methods. The problem is particularly challenging because of the uncontrolled illumination conditions and of the destructive reflection speckle present in most photographs of paintings. A fully automatic imageprocessing chain is described that, starting from several bursts of a painting taken under different angles, permits one to obtain the best possible result by eliminating highlights and motion blur by robust statistics, reducing noise by fusion, and compensating optical distortion in the registration process. This image fusion method is applicable to photographs of a painting taken with a hand-held camera without any particular setup. It works under bad lighting conditions and eliminates motion blur, even when the painting is protected by a glass screen creating structured reflections of the room. The careful discussion of each step of the processing chain also permits one to review and discuss the efficiency of the image fusion tools recently proposed in the literature and insert several new ones in the chain.
This paper presents a new cooperative multi-agent system (MAS) model with the hierarchical and distributed architecture for multi-image processing. This approach is based on the notion of a typical three-level image f...
详细信息
ISBN:
(纸本)9789806560420
This paper presents a new cooperative multi-agent system (MAS) model with the hierarchical and distributed architecture for multi-image processing. This approach is based on the notion of a typical three-level image fusion model, considering that an imageprocessing application can be carried out at pixel-level, feature-level, and decision-level. As an example, the proposed MAS model is applied to the multi modality MR images based human brain tissue segmentation problem, with cooperations achieved between both intra-image agents and inter-image agents. The experimental results have demonstrated the effectiveness of the cooperative multiagent segmentation approach.
A compact visual representation, called the 3D layered, adaptive-resolution, and multi-perspective panorama (LAMP), is proposed for representing large-scale 3D scenes with large variations of depths and obvious occlus...
详细信息
A compact visual representation, called the 3D layered, adaptive-resolution, and multi-perspective panorama (LAMP), is proposed for representing large-scale 3D scenes with large variations of depths and obvious occlusions. Two kinds of 3D LAMP representations are proposed: the relief-like LAMP and the image-based LAMP. Both types of LAMPs concisely represent almost all the information from a long image sequence. Methods to construct LAMP representations from video sequences with dominant translation are provided. The relief-like LAMP is basically a single extended multi-perspective panoramic view image. Each pixel has a pair of texture and depth values, but each pixel may also have multiple pairs of texture-depth values to represent occlusion in layers, in addition to adaptive resolution changing with depth. The image-based LAMP, on the other hand, consists of a set of multi-perspective layers, each of which has a pair of 2D texture and depth maps, but with adaptive time-sampling scales depending on depths of scene points. Several examples of 3D LAMP construction for real image sequences are given. The 3D LAMP is a concise and powerful representation for image-based rendering. (C) 2004 Elsevier Inc. All rights reserved.
This paper presents an efficient image-based approach to navigate a scene based on only three wide-baseline uncalibrated images without the explicit use of a 3D model. After automatically recovering corresponding poin...
详细信息
This paper presents an efficient image-based approach to navigate a scene based on only three wide-baseline uncalibrated images without the explicit use of a 3D model. After automatically recovering corresponding points between each pair of images, an accurate trifocal plane is extracted from the trifocal tensor of these three images. Next, based on a small number of feature marks using a friendly GUI, the correct dense disparity maps are obtained by using our trinocular-stereo algorithm. Employing the barycentric warping scheme with the computed disparity, we can generate an arbitrary novel view within a triangle spanned by three camera centers. Furthermore, after self-calibration of the cameras, 3D objects can be correctly augmented into the virtual environment synthesized by the tri-view morphing algorithm. Three applications of the tri-view morphing algorithm are demonstrated. The first one is 4D video synthesis, which can be used to fill in the gap between a few sparsely located video cameras to synthetically generate a video from a virtual moving camera. This synthetic camera can be used to view the dynamic scene from a novel view instead of the original static camera views. The second application is multiple view morphing, where we can seamlessly fly through the scene over a 2D space constructed by more than three cameras. The last one is dynamic scene synthesis using three still images, where several rigid objects may move in any orientation or direction. After segmenting three reference frames into several layers, the novel views in the dynamic scene can be generated by applying our algorithm. Finally, the experiments are presented to illustrate that a series of photo-realistic virtual views can be generated to fly through a virtual environment covered by several static cameras. (C) 2004 Elsevier Inc. All rights reserved.
暂无评论