Image analysis – Image compression or coding – Quantization
Reexamination Certificate
2007-03-06
2007-03-06
Wu, Jingge (Department: 2623)
Image analysis
Image compression or coding
Quantization
Reexamination Certificate
active
09447554
ABSTRACT:
This invention is a method and apparatus for processing decompressed images. More particularly, this invention relates to methods and apparatus which process images without requiring information on whether the image was previously compressed or how the image was compressed. Quantization values of each image block of a decompressed image are determined a compression method used to compress a decompressed image to be processed is identified. The method and apparatus of this invention is particularly useful to determine if a decompressed image was previously compressed using a JPEG compression technique by retrieving DCT coefficients and determining quantization values to determine original DCT coefficients of a compressed and decompressed image.
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de Queiroz Ricardo L.
Fan Zhigang
Oliff & Berridg,e PLC
Wu Jingge
Xerox Corporation
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