How to render an Unreal asset thumbnail image in another application?

Using the UnrealEd module I can successfully read an assets thumbnail as a TArray<uint8> via a call to FObjectThumbnail::AccessCompressedImageData().
I can then transfer this byte array to a different non-Unreal application (such as an external C# or Java based application) and then render the image. The
problem is the image colors are wrong. I have tried a few different ways of producing/converting the image in the second application, but always the colors are
incorrect. Any help would be greatly appreciated. Thank you.