Ricoh Company, Ltd.

Eiichi Adachi

Shingo Yamaguchi

Yoshinori Wada

Hajime Kanda

Yuji Koseki

Katsuo Murase

Hiroshi Hishida

A store and forward switching type communication control apparatus for use in a facsimile communication system includes a switching unit, a plurality of internal line interfaces, a plurality of external line interfaces, a plurality of facsimile communication units, a tone generator, a memory and a control unit. The internal line interfaces are connected to a plurality of terminal units, such as telephone units and facsimile units, through respective internal lines. The external line interfaces are connected to an external communication network, such as a telephone network. When one of the terminal units is off-hooked, the availability status of the resources, such as the external line interfaces, the facsimile communication units and the memory, which are available to that terminal unit which has been off-hooked is examined and its result of examination is supplied to the terminal unit in question in order to apprise the operator of the current availability status of the resources.

Store and forward switching type communication control apparatus

A coding system for processing color images outputs coded data associated with a unit block with a particular one of the coded data which belongs to a predetermined level plane heading the others, while omitting those coded data which do not include valid data. Codewords adapted to code level plane information are utilized as level plane identification signals. Color information is identified. A color mode ZERO bit and a color mode ONE bit representative of the identified color information are inserted immediately before data in a line-by-line code format, whereby color image signals are transmitted.

Coding system for image processing apparatus

A data transfer system comprising first means operative to successively produce pieces of information each consisting of a limited number of data bits, the pieces of information including those having a predetermined nature, second means responsive to the pieces of information produced by the first means and operative to discriminate pieces of information having the predetermined nature from other pieces of information, third means for counting the pieces of information having the predetermined nature when such pieces of information occur successively, and fourth means responsive to encode the successively occurring pieces of information having the predetermined nature into a single piece of information including a code indicating the predetermined nature and a code indicating the number of the successively occurring pieces of information having the predetermined nature. The system may find typical application in a facsimile equipment.

Data transfer system

A data compression device for a facsimile apparatus or like picture processing apparatus is operable with a desirable coding efficiency to remarkably reduce the transmission time. When the absolute value of a difference between the numbers of transition points of picture signals associated with two adjacent scanning lines is larger than a predetermined run difference coefficient, the device codes the picture signals by a one-dimensional mode coding operation which occurs with respect to the main scan direction only. When the former is equal to or smaller than the latter, the device codes the picture signals in a two-dimensional mode coding operation which occurs with respect to both the main scan direction and the subscan direction.

Data compression device for picture processing apparatus

The present facsimile machine comprises a system control unit, including a pair of central processing units (CPU's), and main and auxiliary power supplies. In one embodiment of the present invention, the second (slave) CPU receives power from the auxiliary power supply to constantly monitor the facsimile system. Upon receipt of a predetermined signal, the second CPU causes the main power supply turned on to render the first (master) CPU operative, thereby the second CPU becomes functionally dependent upon the first CPU. In another embodiment of the present invention, various functions of the facsimile machine are shared by the two CPU's. That is, one CPU is directed to control the communication-related functions with the other CPU directed to control the mechanism-related functions.

Facsimile system control apparatus

A data communication system having an automatic request for repetition ('ARQ') function shifts down its MODEM rate to a slower value when the number of trials of retransmission has reached a predetermined value. In the present system, the predetermined value is supplied from the receiver to the transmitter prior to transmission operation of data from the transmitter to the receiver, thereby allowing to maintain a high use rate of the transmission line without significantly decreasing the overall data transmission speed.

Arq equipped data communication system

An input buffer (16) functions to store one line of data from a scanner (12) while feeding out a previous line to a run length encoder (17). The compressed data is fed from the run length encoder (17) to an output buffer memory (19) having a fixed capacity. The compressed data is fed to the output buffer (19) intermittently while it is fed out of the output buffer (19) continuously for modulation and transmission. In response to a start signal indicating that a line of data has been stored in the input buffer (16), fill bits are fed to the output buffer (19) at high speed until a full signal is generated indicating that the output buffer (19) is full. Then, a sync signal is fed to the output buffer (19) followed by compressed data from the run length encoder (17).

Facsimile transmission apparatus

The identification information addition system is provided with an identification information bearing sheet and a random access memory for storing the identification information in the random access memory with the identification information bearing sheet scanned by a scanner. The identification information stored in the random access memory is picked up when an original document or a recording sheet is scanned by a scanner or a plotter so that the identification information is added to an image information of the original document or of the recording sheet, with part of the original image information replaced with the identification information.

Identification information addition system of facsimile apparatus

An expander (13) expands lines of compressed received data. Each line of compressed data includes data bits followed by fill bits. A sync code follows each compressed line. A memory (14), (16) stores a previous line of expanded data and a current line of expanded data. In response to detection of the sync code corresponding to the previous line of data, the current line of data is stored in the memory while the previous line of data is fed out to a printer (53), (56). Detection of the sync code is inhibited while the previous line of data is being fed out, the feeding out of the previous line of data occuring during the same period of time the current line is being stored. In this manner, fill bits which were converted into a sync code by a transmission error or the like are prevented from being erroneously detected as a true sync code.

Growing community of inventors

Atsugi, Japan

Eiichi Adachi