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Home Page > Organization > OCIO > TOC > File/Web Services > Facsimile Charts > NWS FAX > G4 Compression

Group 4 (G4) Compression

Our facsimile data files are now stored in TIF with Group 4 compression. Our observations indicate a 30% to 60% decrease in file size with this compression scheme over the previous (G3-1D) scheme.

What does this mean for you? You should be able to download the files more quickly and they will take up less space after you have downloaded them. We have tested a number of graphics viewers and have had no problems displaying images; however, not all graphics viewers can view TIF(G4) files. If you do have problems viewing a file, please contact the webmaster.

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Page last modified: May 20, 2011
Page Author: Internet Services Group
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