Raster image vectorizing method based on contour line

Abstract

The invention discloses a raster image vectorizing method based on a contour line. The raster image vectorizing method based on the contour line includes: generating an intensity image corresponding to a raster image firstly, and then establishing an image height field by using the intensity image after being smoothed; extracting equal altitude points in the image height field, and confirming colors of the equal altitude points; establishing parameter curve math expression of the contour line based on the equal altitude points, and conforming the color of an arbitrary point on the contour line. A parameter curve set with color information is vectorization expression of the raster image. When a reestablishment raster image is expressed in vectorization mode, zooming and discretization operations are performed on a vectorized parameter curve according to the size of the raster image to be established, the position and the color of each pixel occupied by the vectorized parameter curve in the image to be established are confirmed, a coloring pixel is used as initial data, and a color diffusion method is used to reestablish the raster image which is expressed in vectorization mode. The raster image vectorizing method based on the contour line can perform multiple scale vectorization processing on various raster images, can use relative parameters to control the data volume of a vector diagram, and can reestablish the raster image multiple in resolution through vector expression.

Description

Technical field [0001] The invention belongs to the field of digital image processing, and relates to a vectorization processing technology of raster images, in particular to a raster image vectorization method based on contour extraction. Background technique [0002] In the field of digital image processing technology, there are two ways to describe an image: raster representation and vector representation. The raster representation describes the image as a rectangular lattice of regular discrete pixels, where each pixel stores a different luminosity value (brightness or color). It means that a larger raster image usually requires more data and occupies a larger storage space; when the raster image is scaled, jagged aliasing is often generated at the boundary contour of the color block area. An image represented by a vector uses geometric primitives such as points, lines, or polygons to represent the image. Compared with raster images, vector images usually require less data ...

AI Technical Summary

Problems solved by technology

[0007] Aiming at the deficiencies of the prior art, the present invention discloses a method for vectorizing raster images based on contour lines, which extracts the contour lines in the height field of the grayscale image of the raster image and uses color diffusion technology to realize the vectorization of the raster image. can make up for the large amount of calculation in the existing vectorization technology, and the image reconstructed by rasterization can be closer to the original image; at the same time, the method of the present invention also supports multi-resolution processing in the vectorization process

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