Hi Bartley, It sounds like the files you are importing are compressed (probably with LZW compression). ER Mapper only stores the full image matrix, which may be much larger as you have discovered. Try saving the resulting image using ECW compression, which is a bit lossy but much more manageable file sizes.
To see how much fidelity is lost with ECW compression, try compressing then uncompressing the image, then subtract the compressed/uncompressed image from the original. I did some experimentation with this when ECW was first released and I was losing some valuable high frequency information which is not acceptable in our applications, so I still use the full fidelity uncompressed images. Good luck, and happy imaging! SRM. Steven R. McMullan, P.Geo. Principal Geophysicist Poseidon Geophysics (Pty) Limited Plot 3423 Matima Crescent Extention 12 Private Bag X018 Gaborone, Botswana Tel +267 351 612 Cell +267 71 300 820 Fax +267 300 787 E-mail [EMAIL PROTECTED] Personal E-mail [EMAIL PROTECTED] -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Bartley Doyle Sent: 09 October 2002 01:44 PM To: '[EMAIL PROTECTED]' Subject: Importing TIF files Hi all, I have imported some TIF files (1Mb each in size - B&W). The resulting image file sizes are 200Mb! Can you tell me if there is a way of (batch preferrably) importing these TIF to a much smaller file size (say 1Mb each)? Regards, Bartley ********************************************************************** Bartley R. Doyle Compass Informatics Tel: +353-1-6705761 / 087-2902343 Fax: +353-1-6703037 Eml: [EMAIL PROTECTED] Pst: 19 Nassau Street, Dublin 2, Ireland Visit www.compass.ie ! And enter the Compass GeoShop at www.compass.ie/geoshop/. *********************************************************************** This email and any files transmitted with it are confidential and may contain commercially sensitive material. They are intended solely for the use of the individual(s) to whom they are addressed and should not be released to a third party without the consent of Compass Informatics. *********************************************************************** ----------------------------------------------------------- To make changes to your subscription, please visit our website, http://www.ermapper.com/technicl/ermapperl/index.htm ----------------------------------------------------------- To make changes to your subscription, please visit our website, http://www.ermapper.com/technicl/ermapperl/index.htm
