Surface detail in non-photorealistic and realistic images

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Texture is used in computer graphics to provide the illusion of a detailed world; virtual buildings, streets, and landscapes have minute details of roughness and rust expressed using texture. Texture synthesis creates the huge quantities of detail needed for the virtual world of a game or film.******Texture is used as well in non-photorealistic rendering (NPR) which seeks to create images in artistic styles, such as painting or pen-and-ink sketching. Historical artworks and illustrations are sometimes magnificently detailed. In computer graphics, such detail would normally be supplied by texture; in NPR, though, texture has been reserved for depicting the media (say, the roughness of the paint) and not used to add detail to the scene shown in the image. Thus, non-photorealistic images have tended to be far less detailed than computer-generated realistic images. I mean to change that by bringing the relatively mature technology of textures into artistic stylization proper, so that the stylization process, far from destroying detail as it does at present, rather adds detail and enriches the visual interest of the stylized image.******Even for realistic images, texture can be improved. Algorithm developers have concentrated on "stationary" texture, whose properties do not vary over an image. "Nonstationary" texture, that does vary, has received comparatively little attention, yet most textures in nature are nonstationary. I will explore new texture synthesis methods for high-quality nonstationary textures, emphasizing specialized algorithms for natural surfaces such as bark and tortoiseshell. I intend first to concentrate on depicting rock surfaces; rocks are immensely varied, but the computer graphics community has concentrated on synthesizing large-scale terrains rather than the rocks of which they are made.******In the proposed work, I will improve textures in realistic and artistic images. I will improve detail depiction in computer-generated artistic images, using simplified textures to depict surface detail of objects in the scene, not only portraying the media used to draw the scene. I will improve automated capabilities to create highly variable textures depicting natural surfaces. Finally, I will improve texture and image editing capabilities by considering a vector representation of the image content. Improvements to texture will have impact throughout commercial computer graphics. Texture is everywhere the tool of choice for depicting surface detail. In commercial applications, much texture is constructed by artists; tools that assist texture manipulation can increase artists' productivity, while better automated synthesis methods can free artists to work elsewhere. *****