PICTURE-WRITING TRANSMISSION SYSTEM

PURPOSE:To always select an optimum retransmission system by measuring a transmission error rate of a transmission line by utilizing a routine bit pattern continued from a training signal, and thereafter, determining the retransmission system. CONSTITUTION:As for writing/picture data which is transmitted to a receiving side facsimile through a telephone circuit 38 from a transmitting side facsimile 31, the number of error bits in a transmission line is counted by comparing a routine bit pattern which is determined in advance and a routine bit pattern continued from a training signal being receiving data by an error bit counter 43 in a receiving side facsimile 32. As a result, a bit error rate in the transmission line and a retransmission system being suitable for its error rate are collated with a selection table 44 of the retransmission system which is stored as a table, a transmission system being suitable for the transmission line is determined from the bit error rate, and it is informed to the transmitting side facsimile 31. In this way, an optimum retransmission system can always be selected.