摘要 |
Bit-map digital image data with one or more color channels is divided into optimum processing units of image size preset in response to a requirement f or the throughput of the computer and the quality of image, the image data unit s are further divided into minimum processing units of image data for each col or channel. The minimum processing units of image data of each column in the lateral direction are converted into two-dimensional vectors with the latera l position x and the luminance y of each pixel and quantized according to the magnitude of the change of the luminance by using the line segment connectin g the start and end points of each column as a reference vector and shaping is carried out. Then the minimum processing units of image data of each line in the vertical direction are similarly converted into two-dimensional vectors with the vertical position z and the luminance y and quantized according to the magnitude of the change of the luminance by using the line segment connecting the start and end points of each line as a reference vector. Thus the data is converted into compressed image data of a matrix structure based on the significance of the luminance information that each pixel has. The compressed image data of minimum processing units are arithmetically compressed, and then compressed image data of optimum processing units is created by integrating all the color channels. By further integrating them, compressed image data on the whole original image is created.
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