I know that intel GPA support DDS BC5s format, but I dont know if there are a tool for read this file, because the common programs not support this format.
someone know a plugin or tool for read and convert a DDS file with this format to a readable DDS (DXT1 - DXT5)?
(Note: I know that I can export textures from GPA to other formats, but I need to know if is possible to export directly to DDS with BC5s format and read this file)
I haven't used this myself, but I've seen that there's a plugin for GIMP that allows you to read/write DDS files: http://registry.gimp.org/node/70
I would suggest trying this plugin -- please let us know if this works for you.
A little more searching came up with this page: http://www.softpedia.com/hubs/View-DDS
Again, I don't know whether these programs allow input of DDS BC5s, but these are a good start.
ps-> it would also help people here if you could tell us what programs you've already tried but found didn't work.