converting formats

install gimp, open picture using gimp, and save as well... whatever

Hello Greg,
To convert images in Ubuntu you can use GIMP, or imagemagick

http://www.imagemagick.org/script/index.php
https://help.ubuntu.com/community/ImageMagick
http://www.gimp.org/
http://docs.gimp.org/en/gimp-images-out.html#gimp-using-fileformats-export-dialog

Please be aware that PSD files are known to be problematic. See
http://ubuntuforums.org/showthread.php?t=825934
http://docs.gimp.org/en/glossary.html

"PSD

    PSD is Adobe Photoshop's native file format, and it is therefore comparable to XCF in complexity. GIMP's ability to handle PSD files is sophisticated but limited: some features of PSD files are not loaded, and only older versions of PSD are supported. Unfortunately, Adobe has now made the Photoshop Software Development Kit — which includes their file format specifications — proprietary, and only available to a limited set of developers approved by Adobe. This does not include the GIMP development team, and the lack of information makes it very difficult to maintain up-to-date support for PSD files.
"