• SLR

  • Bitrate comparison test

mirdumar using gifs to highlight the differences isnt good because gifs have a very limited color palette

Rakly3 Increasing the bitrate of our files will not automatically translate into better image quality.

yes it will (unless you intentionally use some stupid settings to increase the bitrate without a corresponding increase in quality)

Rakly3 Changing from
I-B-P-B-I
to
I-P-P-P-I
can increase quality with a smaller increase to bitrate than simply doubling or tripling the bitrate.

b frames have better coding efficiency... especially for vr content. replacing b frames with p frames will increase bitrate requirement to achieve the same quality so chances are that your example would decrease quality compared to if you just kept b frames and increased bitrate.

Rakly3 If we increase our bitrate, then certain users will have to stream the 6K version instead of the 8K version. Because their internet is too slow fo the higher bitrate 8K.

so the majority of customers should suffer with low quality 8k because a few people with dialup speed connections want to stream 8k? makes total sense... btw median internet connection speed in the us (probably slr's biggest market) is way higher than the appallingly low 22 mbps slr is encoding 8k videos at.

            spacepirate

            using gifs to highlight the differences isnt good because gifs have a very limited color palette

            Sorry, it's animated webp, i wrote gif by mistake.

              spacepirate so the majority of customers should suffer with low quality 8k because a few people with dialup speed connections want to stream 8k? makes total sense

              This could be easily solved by offering two types of 8K for streaming (e.g. 22 and 50 mbps) to make everyone happy. Some studios have this and they call it 8K HD + 8K UHD or 8K medium + 8K high.

                I'm genuinely baffled that SLR staff are arguing that bitrate doesn't matter. Super weird considering the video production industry has had this figured out for literal decades. Compressed 4k blu-rays are put out at 128Mbits/s and initial capture on films is literally Gbits/s but 6k and 8k vr content? sure that should definitely be 30Mbits because "bitrate doesn't matter".

                "Funny" how that promising thread ended with a one-liner in another thread with the exact same generalized statement we've already heard so many times before....

                doublevr Our great @Sandi_SLR is working on a post outlining the whole bitrate business. I can assure you are going to get surprised

                Nobody is actually surprised and now it's not needed anymore. You've already said that you don't care so case closed. Everyone looking for high quality downloads (and streams...) got rected again by SLR. Thanks for nothing.

                    LordCrash there was a ton of internal research involving 10 of our best minds to analyze the every aspect of it. Takes time to put things together. A lot will be clear

                      Streams are actually the best of the best quality.

                      Bottomline 8k 200mbps is an easy way for editors to get the best downloads quality. Then that file is used to create streaming files by super advanced 30mbps max variable bitrate encodings that takes a week for each video.

                      These streaming encodings are magic. The quality is on pars with 200mbps original file for most scenes.

                      We can do smaller size downloads using the same advanced encodings, but it would take too much of resources. Thus we only do it for streaming which is our primary focus for a million reasons.

                        doublevr Dude, there have already been people that proved your 30mbps compression is chopping out data. also: WHY in the world are you shooting 8k at 200mbps. That's an insanely low bitrate for footage, like crazy low. You should be approaching gbps at 8k. That explains why your video quality is so low. For reference, my cheap old fuji XH1 shoots 200mbps for 4k footage and that in no way is considered a professional camera.

                        this one comment by you explains so much of the reduced video quality.

                          doublevr

                          Streams are actually the best of the best quality.

                          Bottomline 8k 200mbps is an easy way for editors to get the best downloads quality. Then that file is used to create streaming files by super advanced 30mbps max variable bitrate encodings that takes a week for each video.

                          These streaming encodings are magic. The quality is on pars with 200mbps original file for most scenes.

                          hahahhaha, you are trolling us, aren't you?

                          If not i don't know what to tell you, i already posted two animated webs they clearly show that there is a loss in quality.

                          Here i reposted one of them again, just look how much detail is lost on her forehead, eyes, under her eyes, nose, and around the nose. hair, lips, basically her whole face.

                          Comparison is between 8K 30mbps and Original 8K 90mbps. Scene is Aubree Valentine "Consumated Passion" from VRHush.

                              Hey, I will follow up today, just wanted to be sure to not bullshit you, so we did many tests.
                              Will try to clear if I can post all the samples we did.

                                Sandi_SLR you'd be better off now explaining why you are shooting 8k at only 200mbps. That's insanely low quality for 8k footage. it's barely acceptable to shoot 4k at 200mbps and even then that's on the low end.

                                    doublevr Streams are actually the best of the best quality.

                                    demonstrably false. slr has the lowest streaming bitrates of any major site. and no.. your "super advanced 30mbps max variable bitrate encodings" (in reality constant bitrate) are not higher quality than content from other sites.

                                    We can do smaller size downloads using the same advanced encodings, but it would take too much of resources. Thus we only do it for streaming which is our primary focus for a million reasons.

                                    encoding 1 extra hq file for new slro scenes is barely any additional resources

                                      bobbytables Hey, we are not shooting at that bitrate, our post production exports at that bitrate before it goes to transcoder to get all the streaming versions.

                                        doublevr These streaming encodings are magic. The quality is on pars with 200mbps original file for most scenes.

                                        The individual perception of video quality is perhaps also magical. 'On par' probably depends on what you are paying attention to. For my part, the best streaming file quality as it is now is perfectly fine for clothing, furniture, wallpapers or floors. But for close-up skin texture, I don't buy that taking away 60-80 % of the data (from a file that is not the original camera file but has already undergone some data reduction in post-production) will make no difference at all. You will clearly see the difference if you have a thing for skin texture looking as real and crisp as possible. The animated picture of @mirdumar is a good representation of this difference.

                                        I can accept the business decision of SLR to not invest resources into encoding additional intermediate bitrates files. But justifying this by saying that due to some kind of magic 30 mbps can be encoded from 200 without the slightest loss in perceived quality, so you wouldn't notice the difference anyway? I am not convinced.

                                          2 years later

                                          Came here from the AV1 thread. It's same story here. People verifiably proving that High Bit Rate matters while SLR staff are telling them they are wrong.

                                            Yeah that moving GIF between the 90 and 30 mpbs version says everything. Not sure why we're still even debating. I'm sure 30 mbps is enough for SOME people. Everybody is different, some won't even see the difference or won't care. But others obviously do.

                                            I'm sure that there's some bitrate where it will be hard to tell the difference with the original and the compressed version. For MP3 that's usually 256kbps, it's very difficult for people to notice difference between the raw data and the compressed data beyond that bitrate in a blind test. For 8k VR there will be a similar bitrate but obviously, that's WAY above 30 Mbps.

                                            If anything, it kinda feelds like 30 Mbps for 8k video is like 128kbps for MP3 audio. Good enough for some, but anybody with good hardware and ears will hate 128 kbps.

                                            petex67 After many tests and comparisons, I found that we need at least 60 Mbps bitrate for 5760x2880 @ 60 FPS @ 8-bit color depth to look acceptable in visual quality. ANY higher value of Resolution or Frames or Color depth and you need to double and triple the bitrate REGARDLESS of the Codec when it comes to HEVC vs AV1 to keep the same level of the acceptable visual quality ESPECIALLY in the outdoor scenes. DON'T listen or believe ANYONE tells you otherwise. End of the story.

                                                petex67 People verifiably proving that High Bit Rate matters while SLR staff are telling them they are wrong.

                                                I see you have only been on here for 17 days. Welcome to the SLR forum with this being the story for everything. Get used to it or walk away while you can.