H.264 compatibility (and few other questions)

[Trial]

Hi,
normally HD=h264 and UHD=h265. I think Nasa has HD as well as UHD channels. A lot of 4K boxes are also not able to play 4k/UHD in h264.

Ralf

[BrokenUnusableAccount]

A lot of 4K boxes are also not able to play 4k/UHD in h264.

Seems like an odd restriction.
Perhaps some H264 hardware is old designs not updated when 4K became a thing.
But you'd think if you're adding H265 you'd update your H264 too.
I guess it mostly doesn't matter in practice.