Firstly described by Benoit B.Mandelbrot in 1970s, fractal theory has been paid more and more attention, especially in fields of image and graphics, for its deep theoretical significance and its tremendous practical value.In this paper, the applications of fractal theory in computer graphics are studied, including extracting the fractal information of images and generating fractal natural scene graphics.In this paper, the fractal dimension of gray images and the IFS parameters of natural scene graphics are extracted. Fractal dimension is usually an effective way that used to describe the non-smooth and non-regular geometry objects in the nature and non-liner systems. Based on mathematical morphology, a fractal dimension estimation algorithm is proposed. After this, we analyse the estimated fractal dimension, and get the conclusion that fractal dimension can be used to segment images. All the algorithms are realized in MATLAB 7.0 .Iterated function system (IFS) is one of the main formation ways to generate fractal graphics, and its attractor is good enough to simulate natural objects and scenery, but it is difficult to find the IFS parameters for simulation. In this paper, a method of the IFS parameters extraction based on the collage theorem is introduced.The method has been programmed with VC6.0, experimental results show that this approach is simple, feasible and the IFS parameters extracted can be used to simulate the natural scene.This paper generates lively fractal plants and fractal hill and implements virtual terrain wandering system. L-system is one of main ways to generate fractal graphics, it is particularly efficient in modeling botanic forms. On the basis of L-system, the pictures of several fractal sets and fractal 2D plants are made. Moreover, in order to get lively and lifelike images, graphics are lead into L-system, and some protean tree images with quadrangle trunks and polygonal leaves are formed in VC 6.0.Using the method of the blend of texture image and terrain data,We implement virtual terrain wandering system by Visual C++ calling the functions in OpenGL under the environment of windows.At last, the problems needed to be solved in the fractal field and the prospect of fractal theory are briefly appraised. |