Abstract: The improved image reading and reproducing apparatus comprising a scanner which reads an image on an original photoelectrically, an image processor which performs specified image processing on image data output from the scanner and a printer which writes the image data output from the image processor into a memory, reads the recording image data sequentially from the memory and records an image on an auxiliary scanned recording material in accordance with the recording image data, satisfies the following relation (1):Tr.gtoreq.(82.5/Vp)+.alpha. (1)where Tr is the time of reading one frame of the original image from the start of image reading with the scanner to the storage of obtained recording image data in the memory in the printer; Vp is the speed of auxiliary scanning of the recording material in the printer; and .alpha. is the overhead time which occurs unavoidably between the recordings of two successive frames of the image in the printer.

Abstract: For fractal image coding optimal scaling factors for the image contents in the domain blocks are searched. Each image is divided into analysis blocks, which jointly represent the whole image. The analysis blocks are embedded in analysis regions, which contain besides the analysis blocks areas with a predetermined signal value. Also, comparison regions are formed, which contain at least parts of the image and which have the same size as the analysis regions. The analysis regions and the comparison regions are Fourier transformed. The transformed signals are converted logarithmically. The logarithmized signals are again Fourier-transformed. One of these signals is converted in its conjugate-complex form before both signals are multiplied. The product is normalized, so that it no longer contains amplitude information. Then the signal is subjected to an inverse Fourier-Transformation. If the signal has been logarithmized then it is de-logarithmized.

Abstract: An encoding/decoding method is provided for lossless compression of digital pictures of all types, including continuous-tone images, graphics, multimedia images of mixed text, graphics and photographs, binary documents and drawings. Continuous-tone mode and binary mode are identified on a pixel-by-pixel basis. In continuous-tone mode, context modeling and prediction are employed involving mostly integer arithmetic and simple logic in a conceptually sophisticated scheme. Both the encoding and decoding techniques are suitable for sequential and progressive transmission, although different specific algorithms may be employed for the different specific cases.