Patent ID: 7313696
Filing Date: 2007-12-25
Classification: G06T,H04N

Abstract:
1. A method for enabling a recipient of an image file of JPEG image data to authenticate the image file of JPEG image data, the image file of JPEG image data having a first section and a second section, the first section containing a predetermined number of blocks of transformed coefficients and the second section containing a predetermined number of blocks of transformed coefficients, comprising: (a) producing a hashing function from the first section of the image file of JPEG image data; (b) producing a first integrity checking value from the hashing function produced from the first section of the image file of JPEG image data; (c) identifying the second section of the image file of JPEG image data, the second section having an encrypted signature string embedded in a least significant transmitted bit plane block of the second section; (d) extracting, from the least significant transmitted bit-plane of the second section of the image file of JPEG image data, the embedded encrypted signature string; (e) decrypting the extracted signature string to recover a second integrity checking value; (f) comparing the recovered second integrity checking value with the first integrity checking value; (g) authenticating the first section of the image file of JPEG image data when the recovered second integrity checking value matches the first integrity checking value; and (h) informing the recipient of the image file of JPEG image data that the image file of JPEG image data is authentic when each section of the image file of JPEG image data has been authenticated by comparing the recovered integrity checking value of each section with the produced integrity checking value of each section.