Hi Alexandre,
> On 30. Apr 2024, at 16:40, Alexandre Petrescu <alexandre.petre...@gmail.com> > wrote: > > > Le 30/04/2024 à 16:32, Sebastian Moeller a écrit : >> Hi Alexandre, >> >> >> >>> On 30. Apr 2024, at 16:25, Alexandre Petrescu via Starlink >>> <starlink@lists.bufferbloat.net> wrote: >>> >>> Colin, >>> 8K usefulness over 4K: the higher the resolution the more it will be >>> possible to zoom in into paused images. It is one of the advantages. >>> People dont do that a lot these days but why not in the future. >> [SM] Because that is how in the past we envisioned the future, see here >> h++ps://www.youtube.com/watch?v=hHwjceFcF2Q 'enhance'... >> >>> Spotify lower quality than CD and still usable: one would check not >>> Spotify, but other services for audiophiles; some of these use 'DSD' >>> formats which go way beyond the so called high-def audio of 384khz sampling >>> freqs. They dont 'stream' but download. It is these higher-than-384khz >>> sampling rates equivalent (e.g. DSD1024 is the equivalent of, I think of >>> something like 10 times CD quality, I think). If Spotify is the king of >>> streamers, in the future other companies might become the kings of >>> something else than 'streaming', a name yet to be invented. >>> For each of them, it is true, normal use will not expose any more advantage >>> than the previous version (no advantage of 8K over 4K, no advantage of >>> 88KHz DVD audio over CD, etc) - yet the progress is ongoing on and on, and >>> nobody comes back to CD or to DVD audio or to SD (standard definition >>> video). >>> Finally, 8K and DSD per se are requirements of just bandwidth. The need of >>> latency should be exposed there, and that is not straightforward. But >>> higher bandwidths will come with lower latencies anyways. >> [SM] How that? Capacity and latency are largely independent... think a semi >> truck full of harddisks from NYC to LA has decent capacity/'bandwidth' but >> lousy latency... > > I agree with you: two distinct parameters, bandwidth and latency. But they > evolve simultenously, relatively bound by a constant relationship. For any > particular link technology (satcom is one) the bandwidth and latency are in > a constant relationship. One grows, the other diminishes. There are > exceptions too, in some details. > > (as for the truck full of harddisks, and jumbo jets full of DVDs - they are > just concepts: striking good examples of how enormous bandwidths are > possible, but still to see in practice; physicsts also talked about a train > transported by a train transported by a train and so on, to overcome the > speed of light: another striking example, but not in practice). [SM] Not any more, but Amazon did offer a a storage truck (for latency insensitive transfers of huge data) h++ps://www.cnbc.com/2024/04/17/aws-stops-selling-snowmobile-truck-for-cloud-migrations.html so this is more than just a concept... > > Alex > >> >> >>> The quest of latency requirements might be, in fact, a quest to see how one >>> could use that low latency technology that is possible and available >>> anyways. >>> Alex >>> Le 30/04/2024 à 16:00, Colin_Higbie via Starlink a écrit : >>>> David Fernández, those bitrates are safe numbers, but many streams could >>>> get by with less at those resolutions. H.265 compression is at a variable >>>> bit rate with simpler scenes requiring less bandwidth. Note that 4K with >>>> HDR (30 bits per pixel rather than 24) consistently also fits within >>>> 25Mbps. >>>> >>>> David Lang, HDR is a requirement for 4K programming. That is not to say >>>> that all 4K streams are in HDR, but in setting a required bandwidth, >>>> because 4K signals can include HDR, the required bandwidth must >>>> accommodate and allow for HDR. That said, I believe all modern 4K >>>> programming on Netflix and Amazon Prime is HDR. Note David Fernández' >>>> point that Spain independently reached the same conclusion as the US >>>> streaming services of 25Mbps requirement for 4K. >>>> >>>> Visually, to a person watching and assuming an OLED (or microLED) display >>>> capable of showing the full color and contrast gamut of HDR (LCD can't >>>> really do it justice, even with miniLED backlighting), the move to HDR >>>> from SDR is more meaningful in most situations than the move from 1080p to >>>> 4K. I don't believe going to further resolutions, scenes beyond 4K (e.g., >>>> 8K), will add anything meaningful to a movie or television viewer over 4K. >>>> Video games could benefit from the added resolution, but lens aberration >>>> in cameras along with focal length and limited depth of field render >>>> blurriness of even a sharp picture greater than the pixel size in most >>>> scenes beyond about 4K - 5.5K. Video games don’t suffer this problem >>>> because those scenes are rendered, eliminating problems from camera >>>> lenses. So video games may still benefit from 8K resolution, but streaming >>>> programming won’t. >>>> >>>> There is precedent for this in the audio streaming world: audio streaming >>>> bitrates have retracted from prior peaks. Even though 48kHz and higher >>>> bitrate audio available on DVD is superior to the audio quality of 44.1kHz >>>> CDs, Spotify and Apple and most other streaming services stream music at >>>> LOWER quality than CD. It’s good enough for most people to not notice the >>>> difference. I don’t see much push in the foreseeable future for >>>> programming beyond UHD (4K + HDR). That’s not to say never, but there’s no >>>> real benefit to it with current camera tech and screen sizes. >>>> >>>> Conclusion: for video streaming needs over the next decade or so, 25Mbps >>>> should be appropriate. As David Fernández rightly points out, H.266 and >>>> other future protocols will improve compression capabilities and reduce >>>> bandwidth needs at any given resolution and color bit depth, adding a bit >>>> more headroom for small improvements. >>>> >>>> Cheers, >>>> Colin >>>> >>>> >>>> >>>> -----Original Message----- >>>> From: Starlink <starlink-boun...@lists.bufferbloat.net> On Behalf Of >>>> starlink-requ...@lists.bufferbloat.net >>>> Sent: Tuesday, April 30, 2024 9:31 AM >>>> To: starlink@lists.bufferbloat.net >>>> Subject: Starlink Digest, Vol 37, Issue 9 >>>> >>>> >>>> >>>> Message: 2 >>>> Date: Tue, 30 Apr 2024 11:54:20 +0200 >>>> From: David Fernández <davidf...@gmail.com> >>>> To: starlink <starlink@lists.bufferbloat.net> >>>> Subject: Re: [Starlink] It’s the Latency, FCC >>>> Message-ID: >>>> <CAC=tz0rrmwjunlvgupw6k8ogadcylq-eyw7bjb209ondwgf...@mail.gmail.com> >>>> Content-Type: text/plain; charset="utf-8" >>>> >>>> Last February, TV broadcasting in Spain left behind SD definitively and >>>> moved to HD as standard quality, also starting to regularly broadcast a >>>> channel with 4K quality. >>>> >>>> A 4K video (2160p) at 30 frames per second, handled with the HEVC >>>> compression codec (H.265), and using 24 bits per pixel, requires 25 Mbit/s. >>>> >>>> Full HD video (1080p) requires 10 Mbit/s. >>>> >>>> For lots of 4K video encoded at < 20 Mbit/s, it may be hard to distinguish >>>> it visually from the HD version of the same video (this was also confirmed >>>> by SBTVD Forum Tests). >>>> >>>> Then, 8K will come, eventually, requiring a minimum of ~32 Mbit/s: >>>> https://dvb.org/news/new-generation-of-terrestrial-services-taking-shape-in-europe >>>> >>>> The latest codec VVC (H.266) may reduce the required data rates by at >>>> least 27%, at the expense of more computing power required, but somehow it >>>> is claimed it will be more energy efficient. >>>> https://dvb.org/news/dvb-prepares-the-way-for-advanced-4k-and-8k-broadcast-and-broadband-television >>>> >>>> Regards, >>>> >>>> David >>>> >>>> Date: Mon, 29 Apr 2024 19:16:27 -0700 (PDT) >>>> From: David Lang <da...@lang.hm> >>>> To: Colin_Higbie <chigb...@higbie.name> >>>> Cc: David Lang <da...@lang.hm>, "starlink@lists.bufferbloat.net" >>>> <starlink@lists.bufferbloat.net> >>>> Subject: Re: [Starlink] Itʼs the Latency, FCC >>>> Message-ID: <srss5qrq-7973-5q87-823p-30pn7o308...@ynat.uz> >>>> Content-Type: text/plain; charset="utf-8"; Format="flowed" >>>> >>>> Amazon, youtube set explicitly to 4k (I didn't say HDR) >>>> >>>> David Lang >>>> >>>> On Tue, 30 Apr 2024, Colin_Higbie wrote: >>>> >>>> >>>>> Date: Tue, 30 Apr 2024 01:30:21 +0000 >>>>> From: Colin_Higbie <chigb...@higbie.name> >>>>> To: David Lang <da...@lang.hm> >>>>> Cc: "starlink@lists.bufferbloat.net" <starlink@lists.bufferbloat.net> >>>>> Subject: RE: [Starlink] Itʼs the Latency, FCC >>>>> >>>>> Was that 4K HDR (not SDR) using the standard protocols that streaming >>>>> >>>> services use (Netflix, Amazon Prime, Disney+, etc.) or was it just some >>>> YouTube 4K SDR videos? YouTube will show "HDR" on the gear icon for >>>> content that's 4K HDR. If it only shows "4K" instead of "HDR," then means >>>> it's SDR. >>>> Note that if YouTube, if left to the default of Auto for streaming >>>> resolution it will also automatically drop the quality to something that >>>> fits within the bandwidth and most of the "4K" content on YouTube is >>>> low-quality and not true UHD content (even beyond missing HDR). For >>>> example, many smartphones will record 4K video, but their optics are not >>>> sufficient to actually have distinct per-pixel image detail, meaning it >>>> compresses down to a smaller image with no real additional loss in picture >>>> quality, but only because it's really a 4K UHD stream to begin with. >>>> >>>>> Note that 4K video compression codecs are lossy, so the lower quality >>>>> the >>>>> >>>> initial image, the lower the bandwidth needed to convey the stream w/o >>>> additional quality loss. The needed bandwidth also changes with scene >>>> complexity. Falling confetti, like on Newy Year's Eve or at the Super Bowl >>>> make for one of the most demanding scenes. Lots of detailed fire and >>>> explosions with fast-moving fast panning full dynamic backgrounds are also >>>> tough for a compressed signal to preserve (but not as hard as a screen >>>> full of falling confetti). >>>> >>>>> I'm dubious that 8Mbps can handle that except for some of the simplest >>>>> >>>> video, like cartoons or fairly static scenes like the news. Those scenes >>>> don't require much data, but that's not the case for all 4K HDR scenes by >>>> any means. >>>> >>>>> It's obviously in Netflix and the other streaming services' interest >>>>> to >>>>> >>>> be able to sell their more expensive 4K HDR service to as many people as >>>> possible. There's a reason they won't offer it to anyone with less than >>>> 25Mbps – they don't want the complaints and service calls. Now, to be >>>> fair, 4K HDR definitely doesn’t typically require 25Mbps, but it's to >>>> their credit that they do include a small bandwidth buffer. In my >>>> experience monitoring bandwidth usage for 4K HDR streaming, 15Mbps is the >>>> minimum if doing nothing else and that will frequently fall short, >>>> depending on the 4K HDR content. >>>> >>>>> Cheers, >>>>> Colin >>>>> >>>>> >>>>> >>>>> -----Original Message----- >>>>> From: David Lang <da...@lang.hm> >>>>> Sent: Monday, April 29, 2024 8:40 PM >>>>> To: Colin Higbie <colin.hig...@scribl.com> >>>>> Cc: starlink@lists.bufferbloat.net >>>>> Subject: Re: [Starlink] Itʼs the Latency, FCC >>>>> >>>>> hmm, before my DSL got disconnected (the carrier decided they didn't >>>>> want >>>>> >>>> to support it any more), I could stream 4k at 8Mb down if there wasn't too >>>> much other activity on the network (doing so at 2x speed was a problem) >>>> >>>>> David Lang >>>>> >>>>> >>>>> On Fri, 15 Mar 2024, Colin Higbie via Starlink wrote: >>>>> >>>>> >>>>>> Date: Fri, 15 Mar 2024 18:32:36 +0000 >>>>>> From: Colin Higbie via Starlink <starlink@lists.bufferbloat.net> >>>>>> Reply-To: Colin Higbie <colin.hig...@scribl.com> >>>>>> To: "starlink@lists.bufferbloat.net" <starlink@lists.bufferbloat.net> >>>>>> Subject: Re: [Starlink] It’s the Latency, FCC >>>>>> >>>>>> >>>>>>> I have now been trying to break the common conflation that download >>>>>>> >>>> "speed" >>>> >>>>>>> means anything at all for day to day, minute to minute, second to >>>>>>> second, use, once you crack 10mbit, now, for over 14 years. Am I >>>>>>> succeeding? I lost the 25/10 battle, and keep pointing at really >>>>>>> terrible latency under load and wifi weirdnesses for many existing >>>>>>> >>>> 100/20 services today. >>>> >>>>>> While I completely agree that latency has bigger impact on how >>>>>> >>>> responsive the Internet feels to use, I do think that 10Mbit is too low >>>> for some standard applications regardless of latency: with the more recent >>>> availability of 4K and higher streaming, that does require a higher >>>> minimum bandwidth to work at all. One could argue that no one NEEDS 4K >>>> streaming, but many families would view this as an important part of what >>>> they do with their Internet (Starlink makes this reliably possible at our >>>> farmhouse). 4K HDR-supporting TV's are among the most popular TVs being >>>> purchased in the U.S. today. Netflix, Amazon, Max, Disney and other >>>> streaming services provide a substantial portion of 4K HDR content. >>>> >>>>>> So, I agree that 25/10 is sufficient, for up to 4k HDR streaming. >>>>>> 100/20 >>>>>> >>>> would provide plenty of bandwidth for multiple concurrent 4K users or a >>>> 1-2 8K streams. >>>> >>>>>> For me, not claiming any special expertise on market needs, just my >>>>>> own >>>>>> >>>> personal assessment on what typical families will need and care about: >>>> >>>>>> Latency: below 50ms under load always feels good except for some >>>>>> intensive gaming (I don't see any benefit to getting loaded latency >>>>>> further below ~20ms for typical applications, with an exception for >>>>>> cloud-based gaming that benefits with lower latency all the way down >>>>>> to about 5ms for young, really fast players, the rest of us won't be >>>>>> able to tell the difference) >>>>>> >>>>>> Download Bandwidth: 10Mbps good enough if not doing UHD video >>>>>> streaming >>>>>> >>>>>> Download Bandwidth: 25 - 100Mbps if doing UHD video streaming, >>>>>> depending on # of streams or if wanting to be ready for 8k >>>>>> >>>>>> Upload Bandwidth: 10Mbps good enough for quality video conferencing, >>>>>> higher only needed for multiple concurrent outbound streams >>>>>> >>>>>> So, for example (and ignoring upload for this), I would rather have >>>>>> >>>> latency at 50ms (under load) and DL bandwidth of 25Mbps than latency of >>>> 1ms with a max bandwidth of 10Mbps, because the super-low latency doesn't >>>> solve the problem with insufficient bandwidth to watch 4K HDR content. >>>> But, I'd also rather have latency of 20ms with 100Mbps DL, then latency >>>> that exceeds 100ms under load with 1Gbps DL bandwidth. I think the >>>> important thing is to reach "good enough" on both, not just excel at one >>>> while falling short of "good enough" on the other. >>>> >>>>>> Note that Starlink handles all of this well, including kids watching >>>>>> >>>> YouTube while my wife and I watch 4K UHD Netflix, except the upload speed >>>> occasionally tops at under 3Mbps for me, causing quality degradation for >>>> outbound video calls (or used to, it seems to have gotten better in recent >>>> months – no problems since sometime in 2023). >>>> >>>>>> Cheers, >>>>>> Colin >>>>>> >>>>>> _______________________________________________ >>>>>> Starlink mailing list >>>>>> Starlink@lists.bufferbloat.net >>>>>> https://lists.bufferbloat.net/listinfo/starlink >>>>>> >>>> -------------- next part -------------- >>>> An HTML attachment was scrubbed... >>>> URL: >>>> <https://lists.bufferbloat.net/pipermail/starlink/attachments/20240430/5572b78b/attachment-0001.html> >>>> _______________________________________________ >>>> Starlink mailing list >>>> Starlink@lists.bufferbloat.net >>>> https://lists.bufferbloat.net/listinfo/starlink >>>> >>> _______________________________________________ >>> Starlink mailing list >>> Starlink@lists.bufferbloat.net >>> https://lists.bufferbloat.net/listinfo/starlink _______________________________________________ Starlink mailing list Starlink@lists.bufferbloat.net https://lists.bufferbloat.net/listinfo/starlink
