Abstract: A data processing system processes digital information representing, for example, an image and supplied at a lower transfer rate from a data source such as an optical disc unit, to produce data in such a form as to be efficiently used by a device of a higher transfer rate such as a CRT display unit. The digital information includes a plurality of groups of data each representing, for example, a portion or a window of the image and added with control data for defining characteristics thereof. While the digital information is read out at a constant entire transfer rate, the plurality of groups of data are transferred at respective transfer rates which vary with a lapse of time. The control data of each group of data is separated therefrom, and the group of data and the separated control data are stored into first and second memories.