How To Open DDS Files
So a lot of people use GIMP because it's free. That's fine and dandy, but there's no BC7 tool for GIMP, which limits your ability to do a lot of things.
The solution is to use photoshop. Bad news is that it's not cheap to get CS6 or CC. Good news is that the old as sin Adobe Photoshop CS2 is free. And the intel plugin works for it.
1. Go to this link: Adobe CS2
2. Hit accept and scroll down to your language, and scroll down to photoshop CS2.
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3. Download the installer, run it as admin, and install with default settings. When it asks for a serial number, it should be to the right of the installer download. (They are X's on my end so I don't get sued haha)
4. Keep Photoshop closed and go to http://gametechdev.github.io/Intel-Texture-Works-Plugin/
5. In the top right hit download zip button.
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6. Unzip the plugin and navigate to the CS2 installation folder, for me it was C:\Program Files (x86)\Adobe\Adobe Photoshop CS2
7. navigate to \Adobe Photoshop CS2\Plug-Ins\File Formats
8. copy the 8bi file from the \IntelTextureWorks_1.0.4.zip\IntelTextureWorks_1.0.4\Plugins\Win32 to \Adobe Photoshop CS2\Plug-Ins\File Formats
9. Go ahead and run photoshop, you should be good to go.
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