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Recompression of Still Images

Chan, Syin (1992) Recompression of Still Images. Technical report. UKC, University of Kent, Canterbury, UK (KAR id:21068)


The effects of subjecting a digital image to more than one step of the lossy JPEG baseline data compression are studied. The performance in terms of the signal-to-noise ratio as well as visual artifacts are observed and presented. Two types of visual artifacts have been identified and they are found to correlate closely to the two types of errors introduced when the Discrete Cosine Transform coefficients undergo repeated quantisation as part of the JPEG compression algorithm. A method is proposed to estimate the amount of errors generated in the process, which may be used to determine if any special processing is required to reduce these errors. Several methods to overcome the more severe artifacts in the images are investigated and the experimental results are presented.

Item Type: Monograph (Technical report)
Subjects: Q Science > QA Mathematics (inc Computing science) > QA 76 Software, computer programming,
Divisions: Faculties > Sciences > School of Computing
Depositing User: Mark Wheadon
Date Deposited: 24 Mar 2010 00:40 UTC
Last Modified: 28 May 2019 14:00 UTC
Resource URI: (The current URI for this page, for reference purposes)
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