Abstract: A color still picture transmission system includes color visible telephones which are coupled to each other through a telephone network. In succession to luminance signal data of all picture elements forming a whole screen, respective averaged values of two kinds of color difference signal data of four picture elements being adjacent to each other are sent from the color visible telephone at a sending party to the color visible telephone at a receiving party through the telephone network, a modem and a network control unit.

Abstract: A system for transmitting image data on a telephone network or equivalent, which typically includes video or visual telephones as apparatus of sending part and receiving part. In the video telephone of sending part, when an image data sending key is operated, a DTMF signal generator included in a modem is started to operated and a specified DTMF signal, for example, DTMF-A signal or DTMF-B signal is sent as a signal DTMF-DTA to a telephone circuit through a network control unit for approximate 300 milliseconds. Succeedingly, in spite of presence or absence of a responsive signal from the video telephone of receiving part, a non-signal state is formed for approximate 75 milliseconds, immediately thereafter, the image data is sent from the video telephone of sending part at a transmission speed of 4,800 bps or 2,400 bps.

Abstract: The invention relates to a reading apparatus provided with a document table. More particularly, it relates to a reading apparatus which automatically detects the presence or absence of a document and/or the size of a document mounted on the document table. The reading apparatus related to the invention is provided with a light source which illuminates the document table and a means for collecting information about light intensity of the document table. The reading apparatus first gains information about light intensity of the document table when the light source is off and that when it is on, and then by comparing these informations, it detects the presence or absence of a document and/or the size of the document. Accordingly, the reading apparatus correctly detects the presence or absence of a document and/or the size of the document without being affected by external light even when the document cover remains open.

Abstract: A printing apparatus and a facsimile equipment incorporating the same according to the present invention are constituted as such that, when printing an original of, for example, A3 size by a printer of A4 size, the original read in the subscanning direction at reading is printed in the main scanning direction at printing, and at the same time, the image data in the main scanning direction and subscanning direction are enlarged or reduced respectively for printing so as to bring the length/widthwise ratio of a hard copy thus obtained equal to those of the original, so that when the facsimile including a A4 size printer receives the original of A3 size, the hard copy without distortion can be obtained with the smaller printer as compared with the original.