摘要 |
A identification data insertion system for digital data includes a DCT calculator (103) for extracting blocks (102) of 8 x 8 pixels from within a current image (101) and performing DCT (discrete cosine transform) calculation for the blocks (102), a quantizer (104) for quantizing data outputted from the DCT calculator (103), a quantization table (105) for being referred to when the quantizer (104) performs quantization, an electronic watermark data insertion element (107) for inserting electronic watermark data (106) into data after quantization, and an encoder (113) for encoding data outputted from the electronic watermark data insertion element (107) to produce MPEG data (114) in which the electronic watermark data (106) are inserted and outputting the MPEG data (114). <IMAGE> |