Verfahren und Gerät zur Bildverarbeitung

摘要

This disclosure relates to an apparatus and method for orthogonally transforming and quantizing, in block units, inputted image data, and subsequently performing image compression by variable-length coding the data. In particular, control is performed in such a manner that the compressed information quantity attains a predetermined quantity when variable-length coding is carried out. Optimum image compression and expansion are performed by scanning data quantized upon taking into consideration the output characteristics of an image output unit and human visual characteristics. Further, by selecting an optimum quantization table in coding or selecting optimum results from a plurality of coded results, management of the image memory is facilitated, and image compression and expansion featuring ease of image editing and treatment can be performed while image quality is maintained. Furthermore, control is executed in such a manner that data access to the image memory attains a predetermined value so as to make possible the combining of images in the image memory. <IMAGE>