| 摘要 |
PROBLEM TO BE SOLVED: To provide an image alteration detecting apparatus which does not require a complex processing in which encryption data and the like is embedded by a watermark method, in order to detect image alteration. SOLUTION: The image alteration detecting apparatus is used when an image photographed with a CCD camera 2 is sent to an image recording/reproducing unit 3 for recording on a videotape, while this image data is sent to an output unit 4 for image reproduction. The apparatus comprises a data reading unit 11, a Fourier transform unit 12, an alteration detecting unit 13, and a display unit 14. The data reading unit 11 reads image data from the recording/reproducing unit 3. The Fourier transform unit 12 inputs image data read at the data reading unit 11 to conduct Fourier transform. The alteration detecting unit 13 detects whether image alteration has been conducted by inputting spatial frequency spectrum obtained by the Fourier transform unit 12 and determining the extent of white noise strength. The display unit 14 displays the fact when alteration is detected by the alteration detecting unit 13. COPYRIGHT: (C)2004,JPO&NCIPI |
