Still/moving picture selection control circuit for video phone system

Claim 1

A still/moving picture selection control circuit for a video phone system comprising: an analog/digital converter for converting input video signals to digital signals by being synchronized with a subcarrier frequency signal; a digital/analog converter for converting and outputting the output signals of the analog/digital converter to analog signals by being synchronized with the subcarrier frequency signal; a still selection unit for outputting pulse signals by the short-circuit of a still switch; a one-frame signal generating unit for generating one-­frame signals by being synchronized with a vertical synchroniz­ing signal when pulse signals are outputted from the still selection unit; a movie signal generating unit for continuously outputting movie control signals by the short-circuit of a movie switch and for stopping the output of movie control signals by the one-frame signals of the one-frame signal generating unit; a still/movie control unit for applying the subcarrier frequency signal to the analog/digital converter only when the one-frame signals are outputted from the one-frame signal generating unit or the movie control signals are outputted from the movie signal generating unit; and a memory section for storing the output signals of the analog/digital converter to a RAM when the one-frame signals are outputted from the one-frame signal generating unit and for applying the signals stored in the RAM to the digital/analog converter when the one-frame signals are not outputted from the one-frame signal generating unit and the movie control signals are not outputted from the movie signal generating unit.