Patent ID: 6735325
Filing Date: 2004-05-11
Classification: G06T,H04N

Abstract:
An electronic watermark insertion apparatus, comprising:frequency region conversion means for performing DCT for an original image to convert the original image into data f(i) of a frequency region where i=1, 2, . . . , n; quantization means for quantizing the data f(i) of the frequency region; partial averaging means for determining a partial average of the data f(i) after the quantization; multiplication means for multiplying the partial average data by electronic watermark data w(i) determined in advance for the individual factors i; addition means for multiplying results of the multiplication by a constant a and adding results of the multiplication for the individual factors i to the data f(i) after the quantization to determine electronic watermark-containing data F(i); and coding means for compression coding the electronic watermark-containing data F(i).