Title:
DIGITAL IMAGE RECORDER
Document Type and Number:
Japanese Patent JPH1198461
Kind Code:
A
Abstract:
PROBLEM TO BE SOLVED: To check a forged image by using an inverse function of a unidirectional function employing a decoding key so as to encrypt index image data generated resulting from sampling received image data. SOLUTION: Input data are given to a DSP 5, where the signal are converted into R, G, jB data corresponding to each pixel and the converted data are given to a compression/expansion processing section 6, in which the data are compressed and the compressed data are interleaved to produce index image data. Then a security processing section 12 applies an inverse function to a unidirectional function to the index image data to encrypt the data by means of decoding key data resulting in producing the encrypted index data. The encrypted index data with security are decoded as encrypted index data by using a unidirectional function and a public key data given in advance. Then the presence of forgery is discriminated by comparing the decoded data with original index image data.
Inventors:
SUGIYAMA HAYAMI
Application Number:
JP25118597A
Publication Date:
April 09, 1999
Filing Date:
September 16, 1997
Export Citation:
Assignee:
SHINKO ELECTRIC CO LTD
International Classes:
G06F12/14; G06F21/60; G06F21/62; G06F21/64; G09C5/00; H04N1/387; H04N1/40; H04N1/44; H04N5/91; H04N5/92; (IPC1-7): H04N5/92; G06F12/14; G09C5/00; H04N1/40; H04N1/44; H04N5/91
Attorney, Agent or Firm:
Masatake Shiga (11 people outside)
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