Degree:
دكتوراه
Date:
الاثنين, أبريل 28, 2008
Abstract:
The goal of this dissertation is to attain a fast texture synthesis technique able to generate visually pleasing results from a sample texture for a wide range of texture categories. Computer graphics applications often use textures to decorate virtual objects in order to increase realism without modifying geometric details. In recent years, texture synthesis has been a useful tool to generate large textures starting from a sample texture. Texture synthesis is also used to fill holes in damaged pictures, or to generate illimitable textures in interactive applications such as games and simulators. In our dissertation, we present our contributions in texture synthesis and editing. The contributions are in three directions, a pixel-based texture synthesis technique, a patch-based texture synthesis technique, and a patch-based texture synthesis and editing technique. For the Pixel-Based technique, we were inspired by the observation that the most common artefacts which occur when synthesizing textures are high- frequency discontinuities. Our technique tries to avoid these artefacts by forcing at least one of the direct neighboring pixels in each causal neighborhood to match within a predetermined threshold. This does not only avoid deterioration of the visual quality, but also results in faster synthesis timings. We demonstrate our technique on a variety of stochastic and structured textures. This causal neighborhood matching is also applied for selecting patches in the Patch-Based technique. This forces the selection of the most suitable patches, and reduces the search space in a very efficient and strict way. In our last technique, irregular patches are copied from the source texture and stitched in the target texture based on the Voronoi diagram cells around main features. The interior part of the feature is not touched, while the cutting and stitching is performed on the background between the features. The technique is fast enough to be used interactively and to edit textures in a simple and easy way.