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Computer vision based indoor localization methods use either an infrastructure of static cameras to track mobile entities (e.g., people, robots) or cameras attached to the mobile entities. Methods in the first category employ object tracking, while the others map images from mobile cameras with images acquired during a configuration stage or extracted from 3D reconstructed models of the space. This paper offers an overview of the computer vision based indoor localization domain, presenting application areas, commercial tools, existing benchmarks, and other reviews. It provides a survey of indoor localization research solutions, proposing a new classification based on the configuration stage (use of known environment data), sensing devices, type of detected elements, and localization method. It groups 70 of the most recent and relevant image based indoor localization methods according to the proposed classification and discusses their advantages and drawbacks. It highlights localization methods that also offer orientation information, as this is required by an increasing number of applications of indoor localization (e.g., augmented reality).

Radiological investigations are common medical practice for the diagnosis of peripheral vascular diseases. Existing visualization methods such as Curved Planar Reformation (CPR) depict calcifications on vessel walls to determine if blood is still able to flow. While it is possible with conventional CPR methods to examine the whole vessel lumen by rotating around the centerline of a vessel, we propose Curvicircular Feature Aggregation (CFA), which aggregates these rotated images into a single view. By eliminating the need for rotation, vessels can be investigated by inspecting only one image. This method can be used as a guidance and visual analysis tool for treatment planning. We present applications of this technique in the medical domain and give feedback from radiologists.

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The most important component of photorealism in Computer Graphics is given by a physically correct approximation of the light transport. Besides the direct illumination from light sources, there is an indirect illumination, produced by the reflections of the light rays on other surfaces of the scene. In Computer Graphics, the process of computing the illumination of a surface by considering both the direct and the indirect illumination is widely known as global illumination. This paper describes several classes of real-time global illumination techniques used in current game engines together with our own implementations of these approaches. All implementations were made in our own framework, specially designed with a multi-pass rendering architecture that allows fast implementation of rendering techniques and the reuse of functionalities. We analyze these classes based on the following criteria: the visual results produced by the indirect diffuse lighting, the ability to produce glossy reflections, shadows, ambient occlusion, subsurface scattering, translucency and volumetric lighting as well as the ability to simulate area lights. We present the quantitative results of our implementations, obtained with the same external parameters for all techniques, thanks to the unified implementations in the same framework. An important observation is that our analysis is focused on the techniques that are based on the rasterization pipeline, thus, the comparison does not include the techniques designed entirely for the ray-tracing pipeline.

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