Image-based Modeling And Rendering Research Articles

Revolution mapping with bump mapping support

Per-pixel Revolution Mapping is an image-based modeling and rendering technique or IBMR (Image-Based Modeling and Rendering). It consists of creating a virtual 3D objects without polygonal meshes. This technique uses a single RGBA texture that stores the needed data to generate the revolved surface. The main problem with this technique is that the 3D revolved models are rendered without realistic surface wrinkles. In this paper, we presented an improvement to enhance the realism of the 3D revolved models by combining the revolution mapping and the bump mapping. In order to synchronize between real-time depth scaling of the microrelief and the resulting shading, we have added a scaling factor that makes it possible to have a realistic depth animation. This new technique creates very convincing 3D models with realistic looking surface wrinkles and allows rendering at interactive frame rates.

Compression of illumination-adjustable images

The image-based modeling and rendering (IBMR) approaches allow the time complexity of synthesizing novel images to be independent of scene complexity. Unfortunately, illumination control (relighting) is no longer trivial under the image-based framework. To relight the image-based scenery, the scene must be captured under various illumination conditions. This drastically increases the data volume. Hence, data compression is a must. In this paper, we describe a compression algorithm for an illumination-adjustable image representation. We focus on compressing constant-viewpoint images. A divide-and-conquer approach is proposed. The compression algorithm consists of three parts which exploit the intrapixel, interpixel, and interchannel data correlations. Experimental result shows that the proposed method not just effectively compresses the data but also outperforms standard image and video coding methods.

Navigation and Illumination Control for Image-Based VR

Simulation sickness in virtual reality applications is usually due to the non-realtime display of virtual environment. Realtime display of arbitrarily complex scene is a hard problem in traditional geometry-based computer graphics. Image-based modeling and rendering (IBMR) provides an alternative approach whose rendering time complexity is independent of scene complexity. However, due to the lack of geometrical information, capabilities that are obvious to geometry-based virtual reality become difficult problems in image-based virtual reality. In this paper we discuss how two fundamental capabilities, navigation and illumination control, can be achieved in image-based virtual reality applications. To navigate an image-based scene, we need to know where pixels should be moved to and how to solve their visibility. While correspondences or optical flows can answer the former question, the visibility is more difficult to answer, as depth information may not be available. Deriving from epipolar geometry, we propose a triangle-based visibility-ordering algorithm, which can correctly resolve the occlusion without depth information. To control the illumination, we propose a new image representation that not just allows navigation but also re-rendering under various illuminations. By treating each image pixel as an ordinary surface element, we measure the apparent BRDF of each pixel from reference images. By manipulating these apparent pixel BRDFs, we are able to re-render (change the illumination of the scene in an image) without any geometry information. Even shadows can be correctly re-rendered.