Storage medium and apparatus and method for recovering information from such medium by oversampling

An apparatus for recovering symbols carried by information storage medium representing digital information, comprising

• sampling means for oversampling in two dimensions said storage medium to produce samples, and
• processing means for storing said samples to obtain a two-dimensional image representation and for generating recovered symbols from said two-dimensional image representation, wherein said processing means includes means for determining symbol locations in said two-dimensional image representation using positional references established by interpolating between locations defined by said positional information.

An apparatus for recovering symbols carried by an information storage medium representing digital information, comprising

• sampling means for oversampling in two dimensions said storage medium to produce samples, and
• processing means for storing said samples to obtain a two-dimensional image representation and for generating recovered symbols from said two-dimensional image representation, wherein said processing means further comprises means for reconstruction filtering to enhance the two-dimensional image representation.

An apparatus for recovering symbols carried by an information storage medium representing digital information, comprising

• sampling means for oversampling in two dimensions said storage medium to produce samples, and
• processing means for storing said samples to obtain a two-dimensional image representation and for generating recovered symbols from said two-dimensional image representation, wherein said processing means further comprises means for minimizing intersymbol interference by filtering said two-dimensional image representation with a filter the characteristics of which are adapted in respond to the amount of intersymbol interference measured in said two-dimensional image representation.

An apparatus for recovering symbols carried by an information storage medium representing digital information, comprising

• sampling means for oversampling in two dimensions said storage medium to produce samples,
• processing means for storing said samples to obtain a two-dimensional image representation and for generating recovered symbols from said two-dimensional image representation, and
• means for generating a digital representation for each of said recovered symbols by comparing the value of each of said recovered symbols to one or more thresholds, said means comprising means for adapting said one or more thresholds in response to statistical characteristics of said recovered symbol values.

An apparatus for recovering symbols carried by an information storage medium representing digital information, comprising

• sampling means for oversampling in two dimensions said storage medium to produce samples,
• processing means for storing said samples to obtain a two-dimensional image representation and for generating recovered symbols from said two-dimensional image representation, and
• means for maximizing the dynamic range of said recovered samples.

An apparatus for recovering symbols carried by an information storage medium, said apparatus comprising

• sampling means for producing samples by oversampling in two dimensions said storage medium carrying two or more blocks of said symbols representing digital information, said symbols of each block being two-dimensionally encoded,
• processing means for storing said samples to successively obtain for each block a two-dimensional image representation and for generating recovered symbols from each two-dimensional image representation, and
• means for forming a continuous data stream from the symbols recovered from two or more blocks.