| 摘要 |
<p>A method of fractal coding of data and apparatus therefor, which method comprises dividing data into domains, determining a set of transformations relating the domains to the data in such a manner as to minimise error between the data and an approximation to the data obtained by application of the transformation, and providing an expression of a series of quantised fractal coefficients characterising the transformations. The data may relate to at least one of an image, speech, handwriting and information representative of the shape of an object. A transformation is characterised in at least two parts, at least one part indicating a domain and at least another (functional) part indicating a value for a measure associatable with a specific domain or aspect thereof. The transformations are determined analytically and preferably without recourse to searching. The transformation coefficients are derived in linear time. The transformation coefficients are the result of a linear relationship between coding complexity and image size. The quantised fractal coefficients are holdable in a store or sendable over a transmission path and retrievable or receivable as appropriate and a representation or simulation of the data reproduceable therefrom. The set of transformations is determinable by at least squares approximation to the data. A method of forward processing of a fractal from its code includes deriving the fixed points of all the transformations needed for the fractal, forming a rounded approximation pixel for each point, and plotting said pixels as a finite approximation to the attractor of the fractal. Only one pixel may be plotted for each rounded approximation. The number of calculations is linearly related to the finite number of pixels in the approximation.</p> |
