EP 1112636 A4 20050216 - WATERMARKING OF DIGITAL IMAGES USING WAVELET AND DISCRETE COSINE TRANSFORMS
Title (en)
WATERMARKING OF DIGITAL IMAGES USING WAVELET AND DISCRETE COSINE TRANSFORMS
Title (de)
WASSERZEICHENMARKIERUNG VON DIGITALEN ABBILDUNGEN UNTER VERWENDUNG VON EINER WAVELET- ODER EINEN DISKRETEN- COSINUS- TRANSFORMATION
Title (fr)
FORMATION DE FILIGRANE DANS DES IMAGES NUMERIQUES UTILISANT DES TRANSFORMEES EN ONDELETTES ET EN COSINUS DISCRETS
Publication
Application
Priority
- KR 19980037273 A 19980910
- KR 19980037274 A 19980910
- US 9920649 W 19990910
Abstract (en)
[origin: WO0016516A1] The present invention relates to a method for embedding a watermark into a black and white or color digital image [D(x)]. Basically the inventive method comprises the steps of transforming the digital image using a wavelet transform [WC(y)], transforming a watermark using discrete cosine transform (DCT), integrating the wavelet-transformed digital image with the DCT-transformed watermark [DW(x) + WC(y)] to insert the watermark into the image, and generating the watermarked image using inverse wavelet transform [D(x)']. For color images, RGB mode is converted into YIQ mode using a conversion matrix and the wavelet transform is applied to the Y-, I-, Q- values. This inventive digital watermarking of a color image is found to be highly robust against lossy compression and other image processing operations, compared to conventionally known methods which are known to be unsuitable for watermarking color images.
IPC 1-7
IPC 8 full level
G06F 17/14 (2006.01); G06T 1/00 (2006.01); G09C 5/00 (2006.01); H04N 1/32 (2006.01); H04N 1/387 (2006.01); H04N 1/40 (2006.01); H04N 1/46 (2006.01); H04N 1/60 (2006.01); H04N 7/24 (2006.01)
CPC (source: EP KR)
G06T 1/00 (2013.01 - KR); G06T 1/0057 (2013.01 - EP); G06T 1/0064 (2013.01 - EP); G09C 5/00 (2013.01 - KR); H04N 1/32154 (2013.01 - EP); H04N 1/3217 (2013.01 - EP); H04N 1/32309 (2013.01 - EP); H04N 1/3232 (2013.01 - EP); H04N 1/387 (2013.01 - KR); G06T 2201/0052 (2013.01 - EP); H04N 2201/3233 (2013.01 - EP); H04N 2201/327 (2013.01 - EP); H04N 2201/328 (2013.01 - EP)
Citation (search report)
- [A] EP 0441702 A1 19910814 - TELEDIFFUSION FSE [FR]
- See references of WO 0016516A1
Designated contracting state (EPC)
AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE
DOCDB simple family (publication)
WO 0016516 A1 20000323; AU 6031199 A 20000403; CN 1325577 A 20011205; EP 1112636 A1 20010704; EP 1112636 A4 20050216; JP 2003505895 A 20030212; KR 20010079788 A 20010822
DOCDB simple family (application)
US 9920649 W 19990910; AU 6031199 A 19990910; CN 99813122 A 19990910; EP 99969197 A 19990910; JP 2000570934 A 19990910; KR 20017003138 A 20010310