运用层次纹理映射的基于图像绘制算法

提出一种基于图像绘制(image-basedrendering,简称IBR)的算法,以发挥图形卡的纹理映射功能,并能表现物体表面的三维凹凸细节.首先将深度图像的像素按其相关深度分为多层纹理图像,然后利用纹理映射的硬件支持,将这些层次纹理图像依次投影到与视点相关的成像面上,以得到所需目标图像.为了避免目标图像上出现空洞,在生成时,将纹素在深度层次上进行扩展.由于层次纹理图像需要较大的存储空间,并且在装入纹理缓冲时要花费大量时间,为此还提出一种基于压缩层次纹理图像的目标图像生成算法.实验表明新算法是有效的,尤其适于处理与整个物体大小相比深度层次不太多的三维景物,如有表面凹凸纹理(浮雕、门窗等)的建筑物表面等.

Image-Based Rendering Through Layered Texture Mapping

An efficient IBR (image-based rendering) method is presented in this paper to take full advantage of the graphics card, which can successfully simulate the 3D bump details on surfaces of object. In this new approach, an original texture with a displacement at each pixel is firstly decomposed into a series of new textures with each one having a same displacement value, called layered textures, or LT. Then, these LTs are used to render the novel view by conventional texture mapping. To avoid gaps in the rendered image, some pixels are to be interpolated and extended in the LTs according to the depth difference between neighbor pixels in the original texture. As these LTs ask for much storage and need a lot of time to be installed into the texture, a method is given to compress these LTs and the corresponding rendering method. Experimental results show the new method is efficient, especially in rendering those objects with a smaller depth range compared with their size, such as relief surfaces buildings.