Fingerprint image compressing method, involves producing pre-compressed image by sequential processing of four pixels of image, and applying discrete cosine transform compression to pre-compressed data for obtaining compressed image

摘要

The method involves receiving data of an image with a set of pixels, and determining whether the data are in color and/or black/white and grey levels. The data is converted into black/white and grey levels when the data of the image is in color. A pre-compressed image is produced by sequential processing of four pixels of the image, and each pixel is represented by two bits. The two bits of the pixels are coded in a byte. A discrete cosine transform (DCT) compression is applied to the pre-compressed data for obtaining a compressed image.