Most graphics in the Tiger Woods games are stored in DDS (DirectDraw Surface) format. If you want to edit any graphics in the game, you'll need software that can deal with these images.
nVidia have a plugin for Photoshop which can handle DDS files. Any other applications which understand the 8BI plugin format (such as 3D Studio MAX) can also use this plugin. Get the plugin from http://developer.nvidia.com/.
Throughout my articles and tutorials I'll assume you are using Photoshop and have this plugin. If you have a different graphics package you will have to find a plugin that works for you.
If you don't have Photoshop or can't get a DDS plugin, there is still a solution for you. EA Sports ship dxtex.exe with the game. You can find it in the game's bin directory.
This program allows you to load images in various formats and save them as DDS images. Read the help for instructions!
http://developer.nvidia.com/ has links to other tools and libraries which may help you out.
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