1. Field of the Invention
The present invention relates to an apparatus for electrically processing image information such as an image file or a facsimile apparatus, and more particularly to such image processing apparatus adapted for processing image information in compressed form, for example image information stored or transmitted in the run-length encoded form using the modified Huffman (M-H) codes.
2. Description of the Prior Art
It has been proposed to read an original image photoelectrically to generate electric image signals, and to transmit such signals to a printer or a file, or to a distant printer apparatus through a transmission line. In the case of such image signal transmission among plural units, satisfactory synchronization is indispensable between the transmitting and receiving units. However, satisfactory image signal transmission cannot be expected by mere synchronization if the signal processing speed is different between the different units.
Accordingly, there has been considered adjustment the speed or timing of transmission by providing at least either one of the transmitting and receiving units, for example a reader and a printer, with a buffer memory and storing the image signals to be transmitted in such buffer memory.
Such a buffer memory requires a certain margin in memory capacity in order to ensure satisfactory synchronization. However an increase in the memory capacity is inevitably limited as it leads to an increase in the cost.
Also in the case that a compression process is involved in the image data handling, the quantity of data after compression varies significantly, so that the number of pages that can be stored in a memory fluctuates according to the case. At the transmission of compressed image data, certain other signals such as timing signals are transmitted simultaneously, and the storage of such other signals into the aforementioned memory gives rise to waste of the memory capacity.