| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a method for embedding data in an image which enables a standard decoder to decode an image in which data are embedded at JPEG coding, enables complete capture of date embedded at decoding even under the user of an irreversible coding method and cause little image deterioration due to data embedding, and a method for extracting the data. SOLUTION: In embedding data in an image, an original image is divided into block units of 8×8 pixels, DCT(discrete cosine transform) is performed in each block unit with respect to the entire image, a quantization table quantizes each block, the data are embedded by replacing a quantized coefficient value with 1-bit data, run length coding and Huffman coding are sequentially performed, and furthermore, a value of the quantization table corresponding to the coefficient value replaced after the quantization is replaced with 1.</p> |
