Method for the storage on and the reproduction from an optically readable record carrier, record carrier for use in the method and apparatus for use in the method

Claim 1

A method of storing groups of n bits on and reproducing them from an optically readable record carrier, which groups each represent an analog signal value, in which said groups are recovered from a signal obtained by reading said record carrier during reproduction, after which said groups are subjected to an interpolation process, in which a group to be substituted for an unreliable group is generated from the groups situated on both sides of the unreliable group by interpolation of said groups and subsequently to a digital-to-analog conversion for converting said groups into the corresponding analog signal values, characterized in that 2 m (m ≥ 1 )analog signal values which are each representative of a data word of m bits correspond to the groups of n bits, said data words are each stored in the record carrier in the form of k (k > 3) groups representing said data word, and per period corresponding to k groups which are representative of said data word the analogue signal obtained by digital-to-analog conversion is sampled at an instant which is situated from both limits of said period of k groups at least at a time interval corresponding to the repetition period of the groups in the signal obtained after read-out.

Claim 2

A method of storing groups of n bits on and reproducing them from an optically readable record carrier, which groups each represent an analog signal value, in which said groups are recovered from a signal obtained by reading said record carrier during reproduction, after which said groups are subjected to an interpolation process, in which a group to be substituted for an unreliable group is generated from the groups situated on both sides of the unreliable group by interpolation of said groups and subsequently to a digital-to-analog conversion for converting said groups into the corresponding analog signal values, characterized in that 2 m (m ≥ 1 )analog signal values which are each representative of a data word of m bits correspond to the groups of n bits, said data words are each stored in the record carrier in the form of k (k > 3) groups representing said data word, and per period corresponding to k groups which are representative of said data word the analogue signal obtained by digital-to-analog conversion is sampled at an instant which is situated from both limits of said period of k groups at least at a time interval corresponding to the repetition period of the groups in the signal obtained after read-out.

Claim 8

A method as claimed in any one of the Claims 1 to 6, characterized in that after sampling the signal is subjected to an analog-to-digital conversion.

Claim 15

An apparatus for usein conjunction with the method as claimed in anyone of the Claims 1 to 7, comprising a read apparatus, a decoding circuit for recovering groups of n bits which each represent an analog signal value from the signal read, an interpolation circuit for generating a substitute group for an unreliable group by interpolation of the groups situated on both sides of said unreliable group, and a digital-to-analog converter for converting said groups into the corresponding analog signal values, characterized by a sampling circuit for sampling the obtained analog signal per period corresponding to k groups representative of said data word at an instant which is situated within both limits of said period of k groups at least at a time interval corresponding to the repetition period of the groups in the output signal of the decoding circuit.

Claim 18

An apparatus for use in conjunction with the method as claimed in anyone of the Claims 1 to 7, characterized in that the apparatus is provided with an analog input for receiving a signal from a compact-disk digital audio player, a sampling circuit for sampling the analogue signal received per period corresponding to k groups representative of said data word at an instant which is situated from both limits of said period of k groups at least at a time interval corresponding to the repetition period of the groups, an analog-to-digital converter whose input is connected to the output of the sampling circuit, and an output for a digital signal, which output is connected to the output of the analog-to-digital converter.