PURPOSE: To transmit an original with an arbitrary part erased at need by replacing all the image information read while a switch to let an operating part work an erasure function is turned on by white lines.

CONSTITUTION: An operation board 4 inputs an operation by an operator and also, transmits information to the operator. A reading erasure switch is provided at the operation board 4, and all the image information read while the switch is turned on are replaced by the white lines. In such a case, reading is performed at every line, and an image read in every case is encoded. A time required for such encoding can be shoretened by providing the reading erasure switch. Such operation is controlled by a CPU 1 based on a program stored in a ROM 2, and an arbitrary line can be erased. Thereby, transmission can be performed in a form in which the arbitrary part of a transmission original can be erased by adding a program at need, which shortens transmission time.