• SLR

  • Bitrate comparison test

doublevr
Please make sure to use different videos for comparions between different bitrates, like 30,000 kbit/s and 60,000 kbit/s.

Like I said in the other thread, higher bitrate is especially valuable for scene with a lot of movement and "background noise", like e.g. plants and trees etc. in outdoor scenes. The difference isn't that glaring in indoor scenes with a fixed background and generally a lot less movement.

I'd suggest an indoor scene with only one girl, an outdoor scene with foliage in the background and something like a harem scene with a lot of movement by different girls etc. While the difference in the first one might only be noticable in some instances it should be a lot more visible in the latter two, given the overall video quality is already decent enough.

With a flexible, uncapped bitrate scenes with a lot of movement should result in higher bitrates anyway.

    doublevr for me the 6k movies usually don't make a huge difference (unless they are particularly well shot).
    If you really want to test it I would suggest this movie as it has very good image quality: https://www.sexlikereal.com/scenes/ass-and-you-shall-receive-28336.
    If it has to be a SLR original I would suggest: https://www.sexlikereal.com/scenes/big-black-tits-28255.
    These clips both have very good image quality which youll especially notice on things like face closeups and off course they are 4000p +.

      doublevr Right now you can take original quality file and the best resolution encoding and tell me if you see the difference.

      Hmm, I believe I already provided comparisons for this a couple years back (October 2020)
      https://forum.sexlikereal.com/d/1091-can-slr-offer-a-higher-quality-h265-option-for-5k-6k-currently-it-is-21mbps/8

      Is this what you're asking for, or something else? With the screenshots I provided in that thread, especially if you look at their forehead between their two eyebrows, you can see the details/bumps on their skin much more distinctly in the original file vs the compressed file. Amplify that by when you are watching in a headset and everything is "zoomed in" and with motion, it makes a noticeable difference for me on a Pimax 8KX.

      Witcher Ex 1
      Notice the bumps on Whitney's forehead area, her eyes, and nose, etc.
      (Original)

      (Rendition)

      Naughty Dorm Ex 2
      This one is really obvious when looking at Melody's face.
      (Original)

      (Rendition)

      More examples in the link thread.

      I mean, there is a reason why 4K HDR Bluray discs (128~ Mbps) still exist and are wayyyy better than 4K HDR streaming (Netflix/Disney/HBO at 20~ Mbps) for the Home Theater enthusiasts. The same applies for VR.

          doublevr They are uncompressed already if the image is opened in a new browser tab. Actually I would recommend to compare within separate tabs too, because you quickly switch between each while staring at the same spot. But I'll email them over to you as well 👍️

              doublevr Curious if it makes sense to see these in VR

              I think mileage will vary depending on the headset used, and the viewing conditions as well as the lighting conditions of each video. Generally speaking, for my casual viewing sessions I will watch the 6k compressed file more often than the Original file for the sake of ease of use, and because sometimes I like to skip around a lot and I don't want to kill my computer.

              But for those times, when I really want to soak in a scene, especially when it's my first time watching it, I prefer the Original file. I noticed a good amount of difference especially with the bigger group scenes, because there is so much more action and movement in each frame. That's when every bit matters, IMO.

                If you're going to do this test do it with a colorful scene with gradients. Bitrate issues become a lot more apparent when you start dropping and muddling color when compensating for artefacts. I'd also try it on a greenscreen video, one of the biggest issues people (especially you based on recent scenes) have is accurately eliminating green and a chunk of that is likely due to bitrate.

                Since we're actually discussing the issues with open end now I want to re-post something I've already posted in another thread on the topic:

                What is Video Bitrate, and how does it Affect Video Quality?
                In simple terms, video bitrate refers to the amount of video bits/data transferred within a second. It is vital to note that video bits are just strings of data that make up the video you watch. They’re more like the digital building blocks of your videos.

                Since bitrate has to do with the amount of ‘data bits’ being transferred along with the ‘rate’ (i.e., speed) at which the transfer is occurring, it is measured in bits per second (bps). Higher variations include kilobits per second (Kbps) and megabits per second (Mbps).

                Basically, when you have a higher bitrate, it means that a larger amount of ‘video bits’ are being uploaded within a second. This naturally leads to a higher quality video relative to its resolution. Also, increasing the bitrate will increase the size of your output video file and result in relatively slower export.

                Conversely, lower bitrate results in lower video quality, smaller size, and faster export.

                Another thing to understand is that you need to use just the right amount of bitrates, as extremely high bitrates would be wasting your bandwidth, and could potentially affect your hardware.

                Bitrate vs. Resolution: Which is More Important for Video Quality?
                Video resolution refers to the number of picture elements (pixels) spread across a display unit. A higher concentration of pixels (a.k.a higher resolution) leads to higher visual quality.

                I’m sure you’ve heard much more about video resolution than video bitrate. But does that make it more important for video quality?

                Well, not exactly.

                Basically, higher resolution yields a clearer picture. On the other hand, higher bitrate yields smoother playback. Thus, a high-res video with low bitrate will produce a cringy output. You could say the same for high bitrate and low resolution.

                In essence, there has to be a balance between high resolution and high bitrate.

                Of course that's only a generalization and VR scenes with little movement shot in an indoor setting with little to no movement in the background probably don't require an ultra-high bitrate every time but there are scenes that benefit substantially by a higher bitrate and a hard cap at 30,000 kbps isn't ideal for best video quality. The more movement and color gradients and stuff you have in a scene the higher the bitrate should be.

                doublevr
                I actually don't think that screenshots are the best way to measure the results of different bitrates. The bitrate dictates how smooth a video plays and that can hardly be captured in stills. It might be a good starting point but it's not very surprising that the difference in screenshots isn't that glaring.

                  doublevr

                  Missed there was a maximum cap for the highest resolution.

                  There's 30Mbps maximum average over 10 seconds time period which roughly corresponds to the player playback cache. This way we can avoid buffering even for very complex parts of the file.

                  Checking with dev team what are our options.

                  Okay, the plan is to test Original file to SLR highest encoding with as many people and see if there's a difference. Please let me know how it worked for you.

                  I LOVE this response. Thank you @doublevr for listening to us and for working with the devs to brainstorm and test solutions.

                  This thread is very promising.

                    Our Unity teamlead is killing it:

                    we can and we have it in plans (no timeline yet), first we need to do a proper research on what would be the best approach. I would like that caching is supported on all platforms and has the flexibility on how and what we want to cache. Either we find a solution that already provides this or we implement it ourselves, but that will take some time to do it properly.

                    That's the spirit 🔥

                    I've watched Original bitrate (which is super laggy and makes the app to crash) vs SLR encoding on Quest Pro. There's a visible difference. Not a game changer, but some improvement for sure. We really want to fix it

                    It's not okay to provide overbitrated download files and underbitrated for streaming. It served us well for up to 6K videos. It's time to update now.

                    I don't think we want ultra high bitrate download files we called "Original" either

                      doublevr Sounds good! As far as I am concerned, I do not need or even want bitrates above 90 Mbit/sec for SLRO original files (a recent one had 190). On the other hand, the FuckPassVR or VRAllure original files have bitrates of approx. 89 Mbit/sec (Source: https://www.sexlikereal.com/virtualreality/mosaic/id/30283, https://www.sexlikereal.com/virtualreality/mosaic/id/32126) and I never had issues playing them on Q2, so I hope you will not remove these HQ files.

                        FuckpassVR, VRHush and LethalHardcoreVR Original bitrates are 90mbps, files are not too big (around 25GB) and quality is great.
                        SLR Original sometimes go over 190mbps with file size up to 100GB.

                          Every one here assumes more bitrate = more better
                          Many even believe more K = more better

                          mirdumar FuckpassVR, VRHush and LethalHardcoreVR Original bitrates are 90mbps

                          90Mbps is a little bit high, but at least FuckpassVR and VRHush also offer 45Mbps as alternative on their website.

                          CzechVR uses 60 or 80Mpbs depending on the scene. For most other studios 60/62Mbps is the maximum they use for 7/8K scenes, so I guess something between 55Mbps and 75Mpbs would be a good compromise between size and quality.