PVRTexTool won't load KTX files created by our library

I’m trying to load a KTX file created by our application into PRTexTool but it refuses to load. The file is located here: https://github.com/highfidelity/hifi/blob/master/interface/resources/images/Default-Sky-9-cubemap.ktx

As far as I can tell it conforms to the KTX specification. It has some non-standard key/value data, but I would hope to be able to load the file even with that present. However, I’ve also tried stripping the file of our key value data and loading that, but it still fails.

Can anyone provide some insight into why this won’t load? Is it a bug in the tool, or a violation of the KTX standard in the file that I’m missing?

Hi Brad,

We have had a look at this issue and the problem is that the format used by the texture is GL_COMPRESSED_SRGB_ALPHA_BPTC_UNORM which is another name for BC7.
PVRTexTool doesn’t support anything above BC3 (DXT5).
We are considering supporting all BC formats in future versions of PVRTexTool but, for the moment, I cannot give you a definite date.