How to Force Texture Compression

I've been experimenting with the MANY different compression options, trying to reduce my file size. When a texture has been compressed, it tells me its size in the Inspector. That's very useful information. But after I change the file's compression setting, it then says "not yet compressed." I'd like to be able to see how the textures's size and appearance are affected, but It looks like the only time textures are compressed is when doing a build, which is pretty time consuming. Refreshing and reimporting do not compress the file. Is it possible to force Unity to compress a texture after its import settings have been changed, without doing a build?

 

You can find an option called "Compress Assets on Import" in the Unity Preferences, under the "General" tab. Have you turned it off?

Edit: Updated post to use correct menu name.

 

Thanks. I thought Unity used to apply the compression settings immediately. I must've unchecked that option somewhere along the line and forgot about it. It's not under Editor settings, but under Unity Preferences, which is why that setting is not project-specific.