Patent ID: 7136341

Claim:
A DVD-R system comprising a record and playback apparatus, said record and playback apparatus including a CPU and a demodulation circuit, wherein said CPU controls said demodulation circuit and operations of said record and playback apparatus including at least one of a recording operation and a playback operation of a DVD-R disk provided with data recording tracks having a surface wobbled at a predetermined frequency and a plurality of prepits formed on said surface with a predetermined phase relation to a position for data recording, said operations further including detecting said prepits when said record and playback apparatus performs said at least one of a recording operation and a playback operation, and generating and outputting prepit signals in response to detecting said prepits, decoding said prepit signals and extracting decoded information data therefrom, receiving said decoded information data and comparing a pattern of said information data to a pattern of predetermined data and outputting said decoded information data with a predetermined error flag if said patterns are not in coincidence with each other, and receiving said error flag and computing a position of an error on a basis of said error flag and providing error correction to said decoded information data.