Playback apparatus for audiovisual disc records

Claim 1

A playback apparatus for disc records in which information is recorded as microscopic pits in radially spaced apart track turns, said information being a sequence of data blocks of multiplexed data words of multi-channel still-picture video signals, data words of multi-channel audio signals and data bits of multi-channel computer-control signals, said audio data words and said computer-control data bits being organized into a sequence of sub-blocks, the volume of information contained in said computer-control data bits of each of said sub-blocks being much smaller than the volume of information contained in said audio data words of each of said sub-blocks, said information further including a first sync code for identifying each data block, a second sync code identifying each sub-block and a third sync code identifying a sequence of said sub-blocks, the apparatus comprising: means for detecting said recorded information from said disc record to recover said sequence of data blocks; means for detecting the first sync code from the recovered data blocks and separating binary digits of still-picture data of each channel from binary digits of the audio and computer-control data of each channel; manual command entry means for generating a channel selection signal in response to a manual command; means for detecting the second and third sync codes from the separated binary digits of the audio and computer-control data; data selecting means responsive to the channel selection signal and the detected second sync code for selecting the audio data words of a desired channel and the computer-control data bits of a desired channel from the separated binary digits of the audio and computer-control data of said channels; video converting means responsive to the selection signal for storing the still-picture data words of a desired channel for a predetermined period and converting the stored data words into an analog video signal for application to a visual display means; audio converting means for converting the selected audio data words into an analog audio signal for application to an electroacoustic means; and decoding means responsive to the detected third sync code for decoding the computer-control binary digits of the selected channel into computer-control data words for application to a personal computer which is coupled to the display means.