| 摘要 |
PURPOSE:To improve transmission efficiency without using a device of a complex constitution, by compressing and transmitting a picture signal together with an added scanning-line density specifying signal corresponding to picture information, and performing picture recording operation with scanning-line density specified on a reception side. CONSTITUTION:A scan on an original 1 is made through a light source 2 to output a picture information signal through a photoelectric converter 3 and a binary coding device 4. A picture information density deciding circuit 8 decides on whether the picture information density of said signal is high or low and a scanning-line density switching signal generation part 12 generates a scanning-line density specifying signal. This specifying signal is added to the picture signal through a mixer 5 and the resulting signal is compressed by a compressing circuit 6 to be transmitted to a reception side. This compressed signal is demodulated by a modem on the reception side, a scanning-line density switching signal separating circuit separates the scanning-line density specifying signal, and a scanning-line density switching signal deciding circuit decides on the specifying signal. Then, necessary bits are applied to the scanning-line density switching circuit to control a subscan motor driving circuit, and thus the constitution of the device is simplified to improve transmission efficiency. |
