Fremgangsmåde og apparat til sikring mod forfalskning ved anvendelse af digital rasterering

摘要

The Invention relates to a method for decoding secondary information combined with a primary image and contained in a document as an anti-counterfeiting security feature, the method comprising the steps of: (a) providing the document in which the secondary information is incorporated; (b) selecting a portion of a plurality of pixels forming the combined image; (c) statistically sampling the selected portion of the plurality of pixels to determine the secondary information; and (d) at least one of processing and displaying the secondary information determined in step (c).