858 research outputs found

    Apparatus and/or method for recognizing printed data in an image

    Get PDF
    A system for recognizing and locating printed data of a known spatial characteristic in an image is described. A digital matched filter is used to identify the presence of the printed data via an auto correlation between the filter coefficients and the printed data. When an auto correlation is identified, approximate areas are selected and further processing is undertaken only within such areas

    Descriptive Complexity of Deterministic Polylogarithmic Time and Space

    Full text link
    We propose logical characterizations of problems solvable in deterministic polylogarithmic time (PolylogTime) and polylogarithmic space (PolylogSpace). We introduce a novel two-sorted logic that separates the elements of the input domain from the bit positions needed to address these elements. We prove that the inflationary and partial fixed point vartiants of this logic capture PolylogTime and PolylogSpace, respectively. In the course of proving that our logic indeed captures PolylogTime on finite ordered structures, we introduce a variant of random-access Turing machines that can access the relations and functions of a structure directly. We investigate whether an explicit predicate for the ordering of the domain is needed in our PolylogTime logic. Finally, we present the open problem of finding an exact characterization of order-invariant queries in PolylogTime.Comment: Submitted to the Journal of Computer and System Science
    • …
    corecore