Color image authentication method based on palette compression technique

專利類型

發明

專利國別 (專利申請國家)

美國

專利申請案號

16/241,959

專利證號

US 10,853,917 B2

專利獲證名稱

Color image authentication method based on palette compression technique

專利所屬機關 (申請機關)

國立高雄科技大學

獲證日期

2020/12/01

技術說明

A secure authentication method for color image access has been proposed. This distortion-free color image authentication method is able to detect, localize and recover the tampered image regions. Concepts of compression and interpolation are utilized to reduce the data volume of a cover image for the purpose of generating authentication signals that simultaneously act as the data for later tampering recovery. Via the use of the (k, n)-threshold method, the generated authentication signals are further transformed into n numeric shares to increase the multiplicity of authentication data for exploiting the fault-tolerance property provided by the (k, n)-threshold method. These shares are then concealed into an alpha channel in a well-planned manner to yield a protected image in the PNG format. An image block is verified as authentic only when the authentication signal computed from the alpha channel by the reverse process of (k, n)-threshold method matches another signal extracted from the current content of the image block. For a block being judged as inauthentic, the computed authentication signal is also taken as a clue to find the corresponding color in the palette to recover it. These processes enhace the security of image access and help to resist impersonation attack.