摘要 |
A method is described of compressing and decompressing digital data that is especially suitable for halftoned image data in which every bit represents the marking of a receiving material by ink or toner. The method is lossless and balances the use of memory, the processing time, the compression factor and the cost of hardware resources. The recurrence of data in halftoned images on which the smaller data size of the compressed data is based, is caused by the use of a halftone dither matrix. Various halftone dither matrices may be used in the halftoned image. The method is adapted to employ the characteristics of a specific halftone dither matrix by applying a dynamic set of offset values, in which an offset value represents a number of words between the current word of digital data and an identical, previously processed word. |