doublevr Actually it might be possible to play 8K 120FPS on modern CPU’s in h264. Testing it out.

even if it is possible its a bad idea for multiple reasons. those files have no chance of playing smoothly on mobile SoCs used in popular standalone headsets, and the other reasons i will probably get banned for mentioning.

4 months later

Quest 3 can decode 8k/120Hz using H265 very smoothly (I verified by doing a frame interpolation on an SLR video). As @doublevr mentioned it's crazy how long it takes to render such files (time = money).

    Iamthemulti The official specs disagree with that and you can be sure that Meta would advertise 8K 120fps support and not 8K 60fps if the Quest 3 could reliably play 8K 120fps.

      I don't remember ever watching a 30 fps video in vr and thinking.. damn, this is ruined by low FPS... but I absolutely can watch low res vr videos and say damn, this 960p / 1080p / 1200p / 1440p / 1600p VR video looks pretty crappy and I wish it were higher resolution

      High resolution is much more future-proof than lower res higher fps. And from my experience so far, frame interpolation (making a 30 or 60 fps video into 120fps) is much easier to do with consistently good results.. like basic, simple settings and 1 click.. compared to AI up-scaling that's full of tinkering, testing, comparing and it's still a roll of the dice on whether anything looks better (because it's trying to add detail that doesn't exist at all natively), or some part of the video looks better but another part is ruined, or detail gets washed out and the video starts looking cartoony.

      Gaming you'd probably want to sacrifice some resolution for frame rate if you can't do both, but I wouldn't with regular video

        Hairsational it can't do 8192x4096 @ 120Hz but it can do 8000x4000 @ 120Hz, feel free to render a video and test yourself. Make sure you use a fast decode/low latency tune in H265.

          TemporaryName I don't remember ever watching a 30 fps video in vr and thinking.. damn, this is ruined by low FPS

          30 fps is totally unwatchable trash for me in most cases but maybe people have different tolerences

          Iamthemulti it can't do 8192x4096 @ 120Hz but it can do 8000x4000 @ 120Hz, feel free to render a video and test yourself. Make sure you use a fast decode/low latency tune in H265.

          Ok sure, so it works for the XR2 gen2 but not in all cases. You need to specifically encode files with encoder features disabled (what the fast decode option does) which lowers the encoding quality. Even then the files won't necessarily be playable on many other devices because every decoder has different limits and most don't officially or unofficially support 8K 120fps.

            Hairsational pretty much all VR videos are encoded with that setting, it's a suggestion that is not specific to 8k/120Hz.

            6144x3072/120Hz works for Quest 2 if I remember correctly

              Iamthemulti pretty much all VR videos are encoded with that setting

              Interested to know what makes you think that? I know for a fact that h265 videos encoded by SLR are not encoded with either of those encoder settings you mentioned.

                Hairsational now you have piqued my curiosity, what other settings does SLR encode with? 2-pass or 3-pass? veryslow or placebo? etc.

                Quality impact for enabling fast-decode/low-latency (it's the same option that goes by different names) is minimal, and greatly improves playback compatibility. When an encoder setting decreases quality by a couple percent you can usually get those couple percent back by just bumping up the bitrates.

                Check this blog from Meta discussing the challenges of client side decoding for AV1 (they specifically name the fast-decode option): https://engineering.fb.com/2023/02/21/video-engineering/av1-codec-facebook-instagram-reels/

                Not trying to hijack this conversation and turn it into a doom9 forum haha

                  We are testing it out. Will follow up shortly

                  Iamthemulti now you have piqued my curiosity, what other settings does SLR encode with? 2-pass or 3-pass? veryslow or placebo? etc.

                  For h265 files: x265, single pass CRF 15, slow preset. Don't be fooled by the CRF 15 though because actual quality is significantly lower than that value suggests due to SLR's use of VBV.

                  Iamthemulti Quality impact for enabling fast-decode/low-latency (it's the same option that goes by different names) is minimal, and greatly improves playback compatibility.

                  Fast decode and low latency options are not the same thing. In x265 the low latency option reduces quality a lot because it disables B frames.

                  Iamthemulti When an encoder setting decreases quality by a couple percent you can usually get those couple percent back by just bumping up the bitrates.

                  You can bump the bitrates to compensate for the quality loss but it doesn't change the fact that the coding efficiency is lower after disabling the settings. Quality at the same bitrate is lower. The only reason to disable such settings is if you specifically want the tradeoff that they offer (e.g. less demands on the decoder at the cost of lower quality or increased bandwidth/file size).

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                  The difference isn't noticeable. Frame interpolation is much easier than resolution enhancement in VR, especially since Topaz Video Enhancer has been trained on 2D films, making it virtually useless for VR upscaling.

                    Some questions about the 120 fps videos that you can find on SLR:

                    • Using Q3 and HS, is it required to activate 120 Hz in both, Q3 and HS settings to fully benefit from 120 fps?
                    • There are some examples like 6K 120 fps 36 GB, 6K Original 60 fps 88 GB. Which one of these is the better version, higher fps/lower bitrate or lower fps/higher bitrate?

                      SchnuppiLilac Using Q3 and HS, is it required to activate 120 Hz in both, Q3 and HS settings to fully benefit from 120 fps?

                      To fully benefit from 120 fps content the headset display needs to be running at 120 Hz. Just look at both the fps counter and the video info/timeline in HS. If you see 120 fps on the fps counter then the display is running at 120 Hz. If you see a frame rate of 119-120 in the video info then the content is 120 fps.

                      There are some examples like 6K 120 fps 36 GB, 6K Original 60 fps 88 GB. Which one of these is the better version, higher fps/lower bitrate or lower fps/higher bitrate?

                      It depends on what you prefer. "Better" is subjective here.

                      Higher quality: the lower fps one
                      Smoother motion: the higher fps one

                      [deleted] especially since Topaz Video Enhancer has been trained on 2D films, making it virtually useless for VR upscaling

                      This is VERY wrong ! For Topaz Video AI there is NO any difference if it upscales 2D or "3D" films as 3D just combines two 2D films ... Actually my experience so far shows that 4K upscale to 8K looks noticeably better then 90% of the VR studios "original" 8K production. Shocking but true ! Just pity AI upscale takes so much time ... but this is the future for sure!

                      Btw about the 120fps topic - have you guys tried to play 60fps vids with steam version of DeoVR trough Virtual Desktop
                      at 120hz with SSW (Synchronous Spacewarp) enabled ? This really makes the 60fps vids looks noticeably smoother - feels very close to real 120fps ... So for me personally this is the ONLY ways to watch VR180 since maybe 2 years already .
                      Once you get used to it that smoothness of SSW and then back to standalone headset video play i am always get the feeling the playback is little jittery ... So if you didnt try this yet i can highly recommend you try it and share your experience here ...

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                        boboweb my experience so far shows that 4K upscale to 8K looks noticeably better then 90% of the VR studios "original" 8K production

                        I disagree. VR upscalling makes films look cartoon-like. Have you seen the notorious Roll Coal?

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                        • Edited

                        boboweb there is NO any difference if it upscales 2D or "3D" films

                        The texture models require fine-tuning for VR. SLR's digital team experimented with this.