Video telephone equipment

Abstract

Abstract PURPOSE: To obtain a smooth displayed picture without a dither by generating and transmitting a video signal, the number of the scanning lines of which is less than the number of the scanning lines to be displayed on a picture receiving part, and at the same time, inserting the scanning line of the signal of a black level into its black scanning line, and displaying it. CONSTITUTION: The video signal from an image pickup part 1 is sent to a picture processing control circuit 5 through a buffer 2, a switch 3 and an AD conversion circuit 4. In the circuit 5, the picture elements of horizontally 100×vertically 100 are extracted according to a synchronizing signal from the image pickup part 1, and for these picture elements, the video signal and the black level signal are alternately outputted from a vertical synchronizing signal to the scanning line of a prescribed order, and transmitted to a receiver 9 and a printer 10 through a DA conversion circuit 7 and an output buffer 8. On the other hand, by the switch operation of 'send' of a control switch 12, the circuit 5 reads out the video signal of a transmission memory 6 according to an instruction from a CPU 11, and transmits it to a telephone line through a modulation circuit 15, an ATT circuit 16, a filter 17 and the switch 19. COPYRIGHT: (C)1989,JPO&Japio

Inventors

• 👤 Akishi Araki
• 👤 Yukinobu Takano
• 👤 Isao Sawachika
• 👤 Toru Minematsu

Bibliographic Details