Patent ID: 7613319
Filing Date: 2009-11-03
Classification: G06T,H04N

Abstract:
1. An electronic watermark generating apparatus comprising: embedding means for embedding to-be-embedded information as an electronic watermark in a quantized block of an irreversible compression image produced by carrying out quantization on a block-by-block basis after an RGB image has been subjected to color conversion to be divided in a plurality of blocks; restoring means for restoring an RGB image by carrying out de-quantization with respect to a block in which to-be-embedded information has been embedded by the embedding means; extracting means for color-converting the restored RGB image and dividing the color-converted RGB image into a plurality of blocks, and then, carrying out quantization on a block-by-block basis, thereby extracting to-be-embedded information from the quantized blocks; re-embedding means for, when it is not checked that the to-be-embedded information has been correctly extracted by checking means for checking whether or not the to-be-embedded information has been correctly extracted by the extracting means, embedding the to-be-embedded information as an electronic watermark again in the quantized blocks; and upper limit value setting means for setting an upper limit value of the repetition count of extracting to-be-embedded information by the extracting means and checking whether or not the to-be-embedded information has been correctly extracted by the checking means.