HD content is macroblocked. Nod to https://en.wikipedia.org/wiki/Macroblock
If content is compressed, I can make a winning bet it has blocks. Even BluRay content has blocks. Where did you get HD content without blocks?
Can anyone tell me what 4k tv has the best upscaling? Looking to buy a 4k tv but also want to be able to watch regular HD content without any macroblocking. Was looking at the Samsung MU 9000

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