EP 0597056 A1 19940518 - METHOD FOR THE MARKING OF DOCUMENTS.
Title (en)
METHOD FOR THE MARKING OF DOCUMENTS.
Title (de)
Dokumentenmarkierungsverfahren.
Title (fr)
PROCEDE DE MARQUAGE DE DOCUMENTS.
Publication
Application
Priority
- CH 173292 A 19920529
- CH 9300135 W 19930526
Abstract (en)
[origin: WO9325038A1] A mark is incorporated to the original during the fabrication of said original in such a way that said mark is invisible on the original but appears on the copy of the original which is made by using a photocopying machine. The mark is incorporated by additionnally mixing the original image to be protected and the marking image to be concealed in the original by modulating one or the other of the images or by manipulation of Fourier transforms.
Abstract (fr)
On incorpore une marque sur l'original lors de l'élaboration dudit original, de façon que cette marque soit invisible sur l'original mais apparaisse sur la copie de l'original effectuée à l'aide d'une photocopieuse. On incorpore la marque en mélangeant d'une façon additive l'image originale à protéger et l'image de marquage à camoufler dans l'original en modulant l'une ou l'autre des images ou par une manipulation de transformées de Fourier.
IPC 1-7
IPC 8 full level
G03G 21/04 (2006.01); G06T 1/00 (2006.01); H04N 1/00 (2006.01); H04N 1/387 (2006.01)
CPC (source: EP US)
G03G 21/043 (2013.01 - EP US); H04N 1/00883 (2013.01 - EP US); H04N 2201/327 (2013.01 - EP US)
Citation (search report)
See references of WO 9325038A1
Designated contracting state (EPC)
AT BE CH DE DK ES FR GB GR IE IT LI LU MC NL PT SE
DOCDB simple family (publication)
WO 9325038 A1 19931209; CA 2114548 A1 19931209; EP 0597056 A1 19940518; JP H06511611 A 19941222; US 5524933 A 19960611
DOCDB simple family (application)
CH 9300135 W 19930526; CA 2114548 A 19930526; EP 93909744 A 19930526; JP 50006094 A 19930526; US 19002194 A 19940128