Patent ID: 7269274
Filing Date: 2007-09-11
Classification: G06T

Abstract:
1. An apparatus for embedding a digital watermark in a document image, comprising: outer shape detection means for detecting circumscribing outer shapes of characters in the document image, said outer shapes including a first outer shape, a second outer shape that neighbors the first outer shape, and a third outer shape that neighbors the second outer shape; reference calculation means for setting a plurality of reference lines, said reference lines extending in a column direction and being spaced apart by a basic pitch in a row direction, said reference lines including a first reference line located between the first outer shape and the second outer shape, and a second reference line located between the second outer shape and the third outer shape; and control means for controlling at least one of the second and third outer shapes so that a distance between the first reference line and an edge of the second outer shape is different from a distance between the second reference line and an edge of the third outer shape, in accordance with digital watermark information to be embedded.