Switching between IP video channels has a much longer latency than switching a dial on an analog TV tuner. This latency is also exhibited on radio listening, be it analog or digital DAB.There's a bit more than that. If you are getting your video channel via IP off a CDN system, then there will need to be:I attribute that to buffer bloat and high latency.It has multiple sources. I suspect the highest latency factor is that of digital processing compared to analog processing; the next factor of latency (by size) may be some buffers related to data transmission, such as IP.The digital processing has huge advantages over analog processing but the large latency of switching between channels (aka 'tuning in') is a clear inconvenient.
* A DNS lookup to see which CDN server is meant to serve your channel, based on your IP address. This is usually done via geolocation lookup, which can take some time. * Your client then needs to contact the CDN server, which may need to import that stream from an origin server elsewhere. To do that properly, it needs to get an idea as to how much sustainable bandwidth there is between you and the CDN server, so the CDN server knows which resolution to request from the origin server. * The CDN server will then want to buffer some of the video to make sure it's not going to suffer from buffer starvation if there's a lag in timely delivery from the remote origin server. That's so your video doesn't go stop-start all that often. * Last but not least, your client then also wants to buffer some in order to be able to deal with irregular deliveries from the CDN server in times of high jitter or packet loss. The more you buffer, the less likely that you'll suffer disruption later. * With video encoding, there's also a need to buffer a few frames just to be able to decode, which can add a part of a second also.Once that's all in place, latency and bufferbloat as such shouldn't matter all that much theoretically, except of course that the protocol that's feeding your client is often still TCP, and they contribute to making life hell for TCP as it's struggling to match its congestion window to the BDP, and the BDP keeps changing due to the buffers filling and emptying. Most TCP connections in video streaming therefore don't get their cwnd anywhere near BDP, as each connection just downloads a chunk of video before the next one takes over for the next chunk.
Alex* * With a happy household user watching streaming media, a second user could have terrible shopping experience with Amazon. The interactive response could be (is often) horrible. (Personally, I would be doing email and working on a shared doc. The Amazon analogy probably applies to more people.) How can we deliver graceful performance to both persons in a household? Is seeking graceful performance too complicated to improve? (I said “graceful” to allow technical flexibility.) Gene ---------------------------------------------- Eugene ChangOn Apr 30, 2024, at 8:05 AM, Colin_Higbie via Starlink <starlink@lists.bufferbloat.net> wrote:[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...Sebastian, nothing but agreement with you that capacity and latency are largely independent (my old dial-up modem connections 25 years ago at ~50kbps had much lower latencies than my original geostationary satellite connections with higher bandwidth). I also agree that both are important in their own ways. I had originally responded (this thread seems to have come back to life from a few months ago) to a point about 10Mbps capacity being sufficient, and that as long as a user has a 10Mbps connection, latency improvements would provide more benefit to most users at that point than further bandwidth increases. I responded that the minimum "sufficient" metric should be higher than 10Mpbs, probably at 25Mbps to support 4K HDR, which is the streaming standard today and likely will be for the foreseeable future.I have not seen any responses that provided a sound argument against that conclusion. A lot of responses like "but 8K is coming" (it's not, only experimental YouTube videos showcase these resolutions to the general public, no studio is making 8K content and no streaming service offers anything in 8K or higher) and "I don't need to watch 4K, 1080p is sufficient for me, so it should be for everyone else too" (personal preference should never be a substitute for market data). Neither of those arguments refutes objective industry standards: 25Mbps is the minimum required bandwidth for multiple of the biggest streaming services.None of this intends to suggest that we should ease off pressure on ISPs to provide low latency connections that don't falter under load. Just want to be sure we all recognize that the floor bandwidth should be set no lower than 25Mbps.However, I would say that depending on usage, for a typical family use, where 25Mbps is "sufficient" for any single stream, even 50ms latency (not great, but much better than a system will have with bad bufferbloat problems that can easily fall to the hundreds of milliseconds) is also "sufficient" for all but specialized applications or competitive gaming. I would also say that if you already have latency at or below 20ms, further gains on latency will be imperceptible to almost all users, where bandwidth increases will at least allow for more simultaneous connections, even if any given stream doesn't really benefit much beyond about 25Mbps.I would also say that for working remotely, for those of us who work with large audio or video files, the ability to transfer multi-hundred MB files from a 1Gbps connection in several seconds instead of several minutes for a 25Mbps connection is a meaningful boost to work effectiveness and productivity, where a latency reduction from 50ms to 10ms wouldn't really yield any material changes to our work.Is 100Mbps and 10ms latency better than 25Mbps and 50ms latency? Of course. Moving to ever more capacity and lower latencies is a good thing on both fronts, but where hardware and engineering costs tend to scale non-linearly as you start pushing against current limits, "sufficiency" is an important metric to keep in mind. Cost matters.Cheers, Colin -----Original Message-----From: Starlink <starlink-boun...@lists.bufferbloat.net> On Behalf Of starlink-requ...@lists.bufferbloat.netSent: Tuesday, April 30, 2024 10:41 AM To: starlink@lists.bufferbloat.net Subject: Starlink Digest, Vol 37, Issue 11 ---------------------------------------------------------------------- Message: 1 Date: Tue, 30 Apr 2024 16:32:51 +0200 From: Sebastian Moeller <moell...@gmx.de> To: Alexandre Petrescu <alexandre.petre...@gmail.com> Cc: Hesham ElBakoury via Starlink <starlink@lists.bufferbloat.net> Subject: Re: [Starlink] It’s the Latency, FCC Message-ID: <d3b2fa53-589f-4f35-958c-4679ec441...@gmx.de> Content-Type: text/plain;charset=utf-8 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...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-sh ape-in-europeThe 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-broa dcast-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: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.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 streaminginitial 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).Note that 4K video compression codecs are lossy, so the lower quality thevideo, 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.I'm dubious that 8Mbps can handle that except for some of the simplestbe 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.It's obviously in Netflix and the other streaming services' interest toCheers, 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 wantto 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, FCCI 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 existing100/20 services today.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.While I completely agree that latency has bigger impact on howwould provide plenty of bandwidth for multiple concurrent 4K users or a 1-2 8K streams.So, I agree that 25/10 is sufficient, for up to 4k HDR streaming. 100/20For me, not claiming any special expertise on market needs, just my ownpersonal assessment on what typical families will need and care about: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.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 haveYouTube 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).Note that Starlink handles all of this well, including kids watchingCheers, 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/2024043 0/5572b78b/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------------------------------ Message: 2 Date: Tue, 30 Apr 2024 16:40:58 +0200 From: Alexandre Petrescu <alexandre.petre...@gmail.com> To: Sebastian Moeller <moell...@gmx.de> Cc: Hesham ElBakoury via Starlink <starlink@lists.bufferbloat.net> Subject: Re: [Starlink] It’s the Latency, FCC Message-ID: <727b07d9-9dc3-43b7-8e17-50b6b7a44...@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed 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:[SM] Because that is how in the past we envisioned the future, see here h++ps://www.youtube.com/watch?v=hHwjceFcF2Q 'enhance'...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.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).AlexThe 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-s hape-in-europeThe 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-bro adcast-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: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.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 streaminginitial 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).Note that 4K video compression codecs are lossy, so the lower quality thevideo, 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.I'm dubious that 8Mbps can handle that except for some of the simplestbe 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.It's obviously in Netflix and the other streaming services' interest toCheers, 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 wantto 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, FCCI 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 existing100/20 services today.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.While I completely agree that latency has bigger impact on howwould provide plenty of bandwidth for multiple concurrent 4K users or a 1-2 8K streams.So, I agree that 25/10 is sufficient, for up to 4k HDR streaming. 100/20personal assessment on what typical families will need and care about:For me, not claiming any special expertise on market needs, just my ownlatency 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.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 haveYouTube 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).Note that Starlink handles all of this well, including kids watchingCheers, Colin _______________________________________________ Starlink mailing list Starlink@lists.bufferbloat.net https://lists.bufferbloat.net/listinfo/starlink-------------- next part -------------- An HTML attachment was scrubbed... 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