Compression Artifacts/Macroblocking in Near Dark scenes (Ultra 2020)
Figured I'd post this here to see if others could help test/replicate the issue and offer any ideas. I posted on AVSforum and someone else did confirm the same issue, but after more testing, I'm wondering if it's an issue specific to the Roku Ultra (2020).
Serious macroblocking/artifacts/blotchy squares in near dark scenes. The squares look like raised blacks and they do something I've heard others describe as "pixel dancing" as they kind of flash and dance around the screen. Now, I know this is 100% caused by compression and just a product of streaming, and it's definitely content/source specific, so I'm fine with the issue existing, however it seems to only be obvious on the Roku Ultra (2020), and not any other devices. I'm focusing on one scene in particular on Netflix. The show is Firefly Lane, S1E5 at 45m11s. There is a closeup and a dark background (see first pic below for example of the scene). The 2nd pic shows the issue (exaggerated with camera flash) and the 3rd pic shows the issue (without camera flash). I did test other scenes like in Meridian for a sanity check, and the cave scene looked pristine on the Ultra, so it's definitely a source/content issue, however why is the Roku Ultra bringing out the artifacts in such a way that no other devices do?
Same scene on different device (exaggerated with flash). Notice you can still see the issue kind of, but the blotches are not really apparent and are more uniform: https://ibb.co/LQwg613
My setup is Roku Ultra (2020) -> Denon x1600H -> LG CX. I also tried Roku Ultra -> LG CX directly and the issue remained, so it's not the AVR.
I tested the scene with Nvidia shield, apple tv, ps4 pro, ub820, and internal LG netflix apps and all did not show this issue.
I also tested all devices on the LG C8 I have, and again, only the Roku Ultra showed the issue.
Internet is 200+ Mbps wired or wireless
Multiple HDMI cables were used
Latest firmware on everything
Would appreciate if others could test the scene out and try to replicate the issue. I find it odd I only see such an issue with the Ultra, so I'm wondering if there is something wrong or if the Ultra is bringing out an unintentional flaw more obviously. It's also odd since I believe the Ultra is TV-LED Dolby Vision, so why would the internal netflix apps look fine?
Re: Compression Artifacts/Macroblocking in Near Dark scenes (Ultra 2020)
Saw your post over on avsforums and now repeated here - figured I'd do some "quick and dirty" testing with my C7.
Watched it in several light levels, with several bitrates, in real-time, paused, and "frame by frame" etc.
Also used the internal NF app for comparison - However, I did update my C7's firmware (06.00.05) last week, which did contain a WebOS version update (3.9.0) a Dolby Vision version update (1.4.4_09.02), and a required NetFlix update (1.5.21)
I couldnt confirm this - I never saw anything akin to it. Again, I wasnt doing anything extensive, just naked-eye, though looking for it.