| 摘要 |
PURPOSE:To transmits the data within a practical time by means of an ordinary telephone line. CONSTITUTION:At the transmission side, the images are inputted through an image scanner or a TV camera, etc., and the data on the color still pictures are decomposed into the red, green and blue colors for each picture element. Then respective intensities of these three colors are decided. An image input device 1 outputs the maximum amplitude equivalent to a single cycle of a sine wave of 3kHz in response to respective intensities of the three colors. The device 1 and an LPF 3 which is connected to a telephone 2 and cuts off the frequency of 3kHz are connected to a mixer 4. The mixer 4 mixes together the voice band signals of the device 1 and the LPF 3 and outputs these mixed signals to an analog telephone line 5. Meanwhile at the reception side, a branching filter 6 connected to the line 5 divides the received voice band signals into the frequency of >=3kHz and the frequency of <=3kHz. Then the signals of the former frequency are sent to a CRT 7 as the image data and the signals of the latter frequency are sent to a telephone 8 respectively. |
