PICTURE PROCESSING METHOD AND PICTURE PROCESSOR

PROBLEM TO BE SOLVED: To precisely read multiplexed auxiliary information by changing the distance from an original point at the time of polar coordinate-displaying a frequency component obtained by executing discrete Fourier transformation on a picture block and repetitively multiplexing auxiliary...

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Bibliographic Details
Main Authors TAKASHIMA YOICHI, NAKAMURA TAKAO, OGAWA HIROSHI
Format Patent
LanguageEnglish
Published 25.09.1998
Edition6
Subjects
ADVERTISING
CALCULATING
CODING OR CIPHERING APPARATUS FOR CRYPTOGRAPHIC OR OTHERPURPOSES INVOLVING THE NEED FOR SECRECY
COMPUTING
COUNTING
CRYPTOGRAPHY
DISPLAY
EDUCATION
ELECTRIC COMMUNICATION TECHNIQUE
ELECTRIC DIGITAL DATA PROCESSING
ELECTRICITY
PHYSICS
PICTORIAL COMMUNICATION, e.g. TELEVISION
SEALS
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Summary:PROBLEM TO BE SOLVED: To precisely read multiplexed auxiliary information by changing the distance from an original point at the time of polar coordinate-displaying a frequency component obtained by executing discrete Fourier transformation on a picture block and repetitively multiplexing auxiliary information and identification information showing the termination of multiplexing for one block. SOLUTION: An original picture 1 is divided into blocks larger than the block size used in general non-reversible compression in a block division part 11 and discrete Fourier transformation is executed at every block in a frequency transformation part 12. A frequency component matrix is obtained and the amplitude of the frequency component is normalized in a frequency component normalizing part 13. The arbitrary component value in the normalized component matrix is changed at a change ratio 18. Auxiliary information 2 is repetitively multiplexed in a multiplex processing part 14. The multiplexed frequency component matrix is inversely normalized and inverse discrete Fourier transformation is executed. Contrast adjustment is executed in a picture contrast adjusting part 16 so that the picture after inverse conversion does not exceed the definition area of a picture element value and a multiplexed picture 3 is obtained.
Bibliography:Application Number: JP19970057516