Bidirectional Texture Function Modeling: A State of the Art Survey

Abstract

Abstract-An ever-growing number of real-world computer vision applications require classification, segmentation, retrieval, or realistic rendering of genuine materials. However, the appearance of real materials dramatically changes with illumination and viewing variations. Thus, the only reliable representation of material visual properties requires capturing of its reflectance in as wide range of light and camera position combinations as possible. This is a principle of the recent most advanced texture representation, the Bidirectional Texture Function (BTF). Multispectral BTF is a seven-dimensional function that depends on view and illumination directions as well as on planar texture coordinates. BTF is typically obtained by measurement of thousands of images covering many combinations of illumination and viewing angles. However, the large size of such measurements has prohibited their practical exploitation in any sensible application until recently. During the last few years, the first BTF measurement, compression, modeling, and rendering methods have emerged. In this paper, we categorize, critically survey, and psychophysically compare such approaches, which were published in this newly arising and important computer vision and graphics area.

Photogrammetry Driven Tools to Support the Restoration Of Open-Air Bronze Surfaces of Sculptures: An Integrated Solution Starting From the Experience of the Neptune Fountain in Bologna

“…The solution to the characterization of these three levels in the case of outdoor bronze surfaces has been defined as follows: • Macroscopic scale: the shape of the surface has been reconstructed as a triangle mesh, with a 0.2 mm accuracy starting from a simple dataset of 9 images. • Mesostructure scale: today's state of the art method for modelling the mesostructure is certainly the Bidirectional Texture Function (BTF), (Filip & Haindl, 2009). To overtake the typical difficulties that characterized this method, a new solution starting from the observation of Kautz (2005), who show that in many cases acquiring some portions without making perceptible errors is enough.…”

Real-Time Visualization of a Sparse Parametric Mixture Model for BTF Rendering

“…Compression must exploit the redundancy in the data in an efficient way, and allow fast decompression for real-time rendering. Refer to [2] and [3] for further details on BTF modeling.…”

“…Parametric Bidirectional Reflectance Distribution Functions (BRDF) are often used to model a material's appearance, but they cannot simulate many complex lighting phenomena such as self-shadowing, self-occlusion, sub-surface scattering and inter-reflections. Instead, image based approaches, such as the Bidirectional Texture Function (BTF), are becoming ever more popular due to the realism they can provide, the improvement in acquisition systems quality and the increasing computational power of GPUs [1][2][3].…”

“…A single BTF can take up several gigabytes of storage, too much to be of practical use in real-time rendering. To tackle this problem, the BTF data must be transformed into a compact and efficiently renderable representation, without compromising image fidelity [2,3,[5][6][7]. Wu et al [8] presented a novel general representation for BTFs, the Sparse Parametric Mixture Model (SPMM).…”

Effects of Approximate Filtering on the Appearance of Bidirectional Texture Functions

“…Previous studies have focused on developing efficient compression algorithms (see [1], [2]). Recently, Filip et al showed that different materials actually require different compression strategies [3].…”