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Netflix is now doing per-shot encoding for UHD content

netflixtechblog.com

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Re: Netflix is now doing per-shot encoding for UHD content

#41

Post by myself248 »

Groxx wrote: post #16
purerandomness wrote: post #7

Earlier quoted context omitted.

That sounds so intuitive that I want to follow up with the question: Why isn't this the default? Is detecting a cut particularly difficult?

Coarsely detecting cuts is relatively simple - look for large frame-to-frame differences (e.g. encode however -> find large frames surrounded by smaller ones -> done, it's as accurate as your perceptual compression is). There are a number of ffmpeg-using tools out there doing this and other "cut to / from black" detection and it's pretty good. Not good enough for a human to say "yeah, these are all scenes", but proba…

Seems to me that if the frame-to-frame difference isn't big enough to detect that way, it's not likely to benefit from a new I-frame, yeah?

Re: Netflix is now doing per-shot encoding for UHD content

#42

Post by michaelt »

notJim wrote: post #31
radley wrote: post #20

> Sometimes we ingest a title that would need more bits at the highest end of the quality spectrum — even higher than the 16 Mbps limit of the fixed-bitrate ladder. From just a cursory inspection using my Apple TV 4K, 12 Mbps is their target bitrate but their ceiling was ~16 Mbps. That's still only a third of what AppleTV+ offers (36/48) and only 2/3 of Disney+ (18/24). Netflix is still higher than Prime Video (10/14…

> From just a cursory inspection using my Apple TV 4K I'm confused, how are you getting this information? Does Apple TV have a way to display the bitrate ceiling? Also, do you find the bitrate differences noticeable? On my 4k tv, I find Netflix looks pretty good, but Amazon looks pretty bad and HBO Now is awful of course (no Max yet, since I use a Roku.) This might be enough to get me to check out AppleTV+.

> how are you getting this information?

Does your router report its current throughput?

Re: Netflix is now doing per-shot encoding for UHD content

#43

Post by [deleted] »

wtallis wrote: post #14

A lot of those graphs seem to show that video quality at 1920x1080 is going down significantly. Does that mean you now need to be on their most expensive plan and using one of their approved devices/platforms to continue receiving the same video quality, now only obtainable with 2560x1440 and higher resolutions?

[deleted]

Re: Netflix is now doing per-shot encoding for UHD content

#44

Post by duskwuff »

wtallis wrote: post #34
hn_check wrote: post #25

Earlier quoted context omitted.

The chart does not see to show every bitrate for every target resolution, but rather is show where the 4K stream would have to drop to a lower resolution given insufficient bandwidth.

https://miro.medium.com/max/2000/1*c28F7YXjNo-GpmB9bBmbrA.pn... This chart clearly shows multiple data points per resolution under the old fixed-ladder scheme, and under the new scheme the new data point for 1080p is lower on the video quality scale than any of the old 720p encodes. That's a pretty significant difference, and my question about where these new encodes fit into their existing price structure remains va…

The article addresses this point:

> As a side note, we do have some additional points, not shown in the plots, that are used in resolution limited scenarios — such as a streaming session limited to 720p or 1080p highest encoding resolution. Such points lie under (or to the right of) the convex hull main ladder curve but allow quality to ramp up in resolution limited scenarios.

Re: Netflix is now doing per-shot encoding for UHD content

#45

Post by fock »

notJim wrote: post #33
fock wrote: post #30

Earlier quoted context omitted.

I just stopped caring, bought a Blu-Ray drive, which works fine under Linux nowadays and can enjoy 30Mbps FHD-encodings where I can just hit pause and have a photo-like still (everything sharp, no blocky shadows). Oh and yes, I also can buy 2 discs/per month of actual good movies I really want to watch (who has time for more than that anyway?) for what Netflix would like to charge me...

You can also get Blu-rays from Netflix if you watch more. The real costly thing for this approach is tv though, isn't it?

I'm in Europe, so I can get blu-rays from some alternative source, but not from Netflix.

Re: Netflix is now doing per-shot encoding for UHD content

#47

Post by nhoughto »

Groxx wrote: post #16
purerandomness wrote: post #7

Earlier quoted context omitted.

That sounds so intuitive that I want to follow up with the question: Why isn't this the default? Is detecting a cut particularly difficult?

Coarsely detecting cuts is relatively simple - look for large frame-to-frame differences (e.g. encode however -> find large frames surrounded by smaller ones -> done, it's as accurate as your perceptual compression is). There are a number of ffmpeg-using tools out there doing this and other "cut to / from black" detection and it's pretty good. Not good enough for a human to say "yeah, these are all scenes", but proba…

Interesting that it makes sense now because the economics of it have shifted, as the shift away from broadcast and towards individual stream has happened.

Re: Netflix is now doing per-shot encoding for UHD content

#48

Post by fock »

RandallBrown wrote: post #40
fock wrote: post #30

Earlier quoted context omitted.

I just stopped caring, bought a Blu-Ray drive, which works fine under Linux nowadays and can enjoy 30Mbps FHD-encodings where I can just hit pause and have a photo-like still (everything sharp, no blocky shadows). Oh and yes, I also can buy 2 discs/per month of actual good movies I really want to watch (who has time for more than that anyway?) for what Netflix would like to charge me...

I personally have way more than ~4 hours of movie watching time per month. I usually spend about an hour (often more) per day watching movies and TV shows on Netflix, HBO, Hulu, etc. I've never cared too much about the quality though. The old school dvd rips that were compressed to 700mb to fit on a CD were usually fine by me.

yes, if you like to do that and find stuff, it's great. Especially if you're a fan of their comedy stuff (which is about the same level as public TV here... - just a little more international). If you'd like to watch a nice movie you get about 1 good one per 2 months.

Re: Netflix is now doing per-shot encoding for UHD content

#49

Post by chiph »

ProfessorLayton wrote: post #39
radley wrote: post #20

> Sometimes we ingest a title that would need more bits at the highest end of the quality spectrum — even higher than the 16 Mbps limit of the fixed-bitrate ladder. From just a cursory inspection using my Apple TV 4K, 12 Mbps is their target bitrate but their ceiling was ~16 Mbps. That's still only a third of what AppleTV+ offers (36/48) and only 2/3 of Disney+ (18/24). Netflix is still higher than Prime Video (10/14…

I've noticed that ATV+ looks the best, which is much appreciated. However, what has been driving me insane with all these services is how the bitrate is completely inconsistent throughout, depending on network congestion. Every service I subscribe to will "automagically" lower the bitrate if the network can't handle it. Which is fine, I get it. The thing is, it's the only way to watch anything, and depending on the c…

And this is why I still get discs by mail. No dropouts, no unexplained drops in resolution, and it has a deeper catalog.

Re: Netflix is now doing per-shot encoding for UHD content

#50

Post by charrondev »

sjwright wrote: post #37
charrondev wrote: post #32

Earlier quoted context omitted.

I also have a 4K LG TV and “frame rate thunking” is the perfect term to describe it. I wish it would just give the direct output to the TV and receiver (video audio). No idea why they the need to process it all on device.

Have you tried turning “match frame rate” on?

I had tried it a while back stopped because anytime you go into or out of video streaming it would black out the whole screen for a second or two before starting to buffer the content. It’s particularly annoying if trying to search for a particular episode of something.

That’s probably the ticket for it though. I find the lack of audio pass through to be the more annoying piece though. I have a machine that costs significantly more than the Apple TV and has knowledge of all of the attached speakers to do that decoding.

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