I have done many tests in CinGG, but nothing works because no hardware
device is seen, opencl filters are not seen, and the .opts file I make
is not seen. No errors, they are simply not seen....
this is strange, I mean that opts files do not work for you.
The only thing left for me to try is to compile trying to enable
"-enable-opencl".
yeah, it seems without this compile-time configure option internal ffmpeg does not know about opencl.
Still, you can try to build --without-thirdparty and thus link to system's ffmpeg.
Sorry for not discovering this earlier.