Inside Netflix’s Plan to Boost Streaming Quality and Unclog the Internet

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According to this report, Netflix is changing its current “one-size-fits-all” model in favor of a per title approach that would mean higher quality with less data usage.

Netflix now has begun to embark on one of the biggest changes to its streaming technology since it launched its online video service in 2007. If all goes according to plan, the switch could help consumers get better-looking streams while also saving up to 20 percent of data — which is significant in North America, where Netflix usage single-handedly accounts for more than a third of all data consumed during peak times, and an even bigger deal in all those countries with relatively slow internet speeds that the company is looking to enter in 2016.
 
I thought VBR is already doing this:

"And then there is another crazy idea that could require the company to re-encode the entire catalog all over again: After finding the best setting for each single video, Aaron’s team is now thinking about even encoding each scene of a movie or TV show with different settings to account for higher information density during fight scenes and lower demands during slow moments of introspection."
 
joseardzm said:
I thought VBR is already doing this:

"And then there is another crazy idea that could require the company to re-encode the entire catalog all over again: After finding the best setting for each single video, Aaron’s team is now thinking about even encoding each scene of a movie or TV show with different settings to account for higher information density during fight scenes and lower demands during slow moments of introspection."
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Yeah kind of a weird announcement, unless it's just for earning season. (Netflix's Q4 report is on 1/19/2016)

Is there a difference with encoding between streamed content vs download content?
 
Mav451 said:
Yeah kind of a weird announcement, unless it's just for earning season. (Netflix's Q4 report is on 1/19/2016)

Is there a difference with encoding between streamed content vs download content?
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Ideally there wouldn't have to be. Real world is that you need an acceptable bit rate that can be streamed without buffer issues. If it's just for a download, then big fat files just DL until they're done, and then you watch.
 
Does netflix use VBR? Even if they did I don't think that really fits this. You would still have peaks and troughs of bandwidth based on the current bitrate. The peak has to be under your max allocated based on current connection speed.

Sounds like netflix was using just bitrate across the board and scaling resolution with it. You need to use a separate factor to determine quality, not bitrate. Handbrake has this setting just labeled "quality" I believe. Bitrate to maintain a quality rating of X would vary based on source material. I think that is what netflix is doing now. If you hit some quality rating they determine is good enough, they will not encode the video at any higher bitrates. Before the only qualifier was bitrate. So they were wasting bandwidth on little to no gains in perceivable quality because they had a global metric instead of a varying one based on the current video.

They have all kinds of fancy algorithms for compression these days, but basic quantization and DCT explains a lot (https://en.wikipedia.org/wiki/Quantization_(image_processing)). Your "quality" rating would be the difference between the original video and new transcode video. I suspect in a logarithmic SNR scale (https://en.wikipedia.org/wiki/Signal-to-noise_ratio) .
 
Netflix could just shut itself down if it wanted to actually solve any problems its creating by offering its service.
 
joseardzm said:
I thought VBR is already doing this:

"And then there is another crazy idea that could require the company to re-encode the entire catalog all over again: After finding the best setting for each single video, Aaron’s team is now thinking about even encoding each scene of a movie or TV show with different settings to account for higher information density during fight scenes and lower demands during slow moments of introspection."
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Possibly not. The old Netflix used a fix-rate encoding of the video at various speeds, and kept them synchronized together. This gave the APPEARANCE of "VBR" streaming to the end user.

This sounds like they will be changing fro fixed bitrate streams to "target quality level" streams like x264/Handbrake now supports:

https://trac.handbrake.fr/wiki/ConstantQuality

My experience with constant quality encoding: not only is it much faster than the old 2-pass, there no more guesswork on what bitrate your video needs. BONUS: depending on the complexity of the video, you can get a size up to 2-4x smaller :D

Technology marches onward, as nobody I know used the constant quality encoder setting five years ago. But now it's the goto setting!
 
defaultluser said:
Possibly not. The old Netflix used a fix-rate encoding of the video at various speeds, and kept them synchronized together. This gave the APPEARANCE of "VBR" streaming to the end user.

This sounds like they will be changing fro fixed bitrate streams to "target quality level" streams like x264/Handbrake now supports:

https://trac.handbrake.fr/wiki/ConstantQuality

My experience with constant quality encoding: not only is it much faster than the old 2-pass, there no more guesswork on what bitrate your video needs. BONUS: depending on the complexity of the video, you can get a size up to 2-4x smaller :D

Technology marches onward, as nobody I know used the constant quality encoder setting five years ago. But now it's the goto setting!
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I always use the constant quality on my videos. It works well. Two similar length movies could be gigs apart. An action film with a lot of bright scenes may come in at 4Gb wereas a drama with a lot of dark scenes may come in at 2Gb.
 
Spidey329 said:
I always use the constant quality on my videos. It works well. Two similar length movies could be gigs apart. An action film with a lot of bright scenes may come in at 4Gb wereas a drama with a lot of dark scenes may come in at 2Gb.
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Yeah, the only problem they have there is making sure they can still synchronize those different quality level streams easily. THAT is the tough question Netflix has to anster.

Another thought I just had: if the higher quality encodes produce the exact same result, if you had software smart enough to detect this, you could deduplicate the "higher quality" stream frames that are exactly the same.

So the quality-based encoding could not only save you streaming bandwidth, but server data storage space as well. Once you stop treating video as fixed numbers and can quantify quality level, the options are endless :D
 
OFaceSIG said:
Depending on how you watch it some don't even get 1080p. The silverlight plugin is only 720p. The netflix win8 tile app is 1080p.
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Any idea what the Xbox One or PS4 app is streaming at? Roku?

I think they need to work on improving quality. 4K TV's are in more and more homes, but very little content. I saw a ton of them leaving Costco the other day. May not be as many as 1080P TV's, but they are increasing in sales. Of course, it could be like when the first HD TV's came out. People using DVD's or using composite video inputs vs. HDMI. They just don't care.

Really, though, there needs to be a big push and education of the consumer showing how limiting the ISP's are. Low speeds, high prices, caps - all limiting the content the consumer could have.
 
Ur_Mom said:
Any idea what the Xbox One or PS4 app is streaming at?
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Definitely not 4k, because the consoles don't officially support it. But I expect they could add a h.265 decoder chip sometime soon as a platform refresh. They'll probably wait a couple years for 4k content and TVs to become a little more widespread though.

I'll say one thing: the fast uptake of streaming makes higher resolution support a lot easier than last generation: it''s a whole lot cheaper to add a decoder chip than to add-on a whole HD-DVD drive :D

Since the PS3 and 360 both supported 1080p streaming, both consoles have to be doing at least that high a resolution.

Roku?
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Roku 3 = 1080p

Roku 4= 4k.
 
It sounds to me like they're gearing up to offer tiered bandwidth pricing. This would align with them previously paying Comcast for preferred access.
 
Kind of stunned at how behind the technology curve Netflix actually are.

But I am VERY sceptical that there will be no loss of quality with the "new" encoding technique.
 
Stimpy88 said:
But I am VERY sceptical that there will be no loss of quality with the "new" encoding technique.
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Depends on who you're talking to.

Ask my wife if there is a loss of quality with Netflix vs. Blu-ray. Nope, none.

Ask me or many people here - Hell yea there is a difference! Give me Blu-ray!
 
I just read that Bell is going to offer Netflix as a channel on Bell Fibe.
 
defaultluser said:
My experience with constant quality encoding: not only is it much faster than the old 2-pass, there no more guesswork on what bitrate your video needs. BONUS: depending on the complexity of the video, you can get a size up to 2-4x smaller :D

Technology marches onward, as nobody I know used the constant quality encoder setting five years ago. But now it's the goto setting!
Click to expand...

I was very hesitant at first because I just couldn't believe that a 1080p live action film could be 14GB, but a 1080p animation could be 4GB. So I assumed it was messed up. But I did some viewing and I came to the conclusion that it really does know what it's doing. You'll get anomalies here and there, like films with a lot of night shots AND a lot of film grain...those will be fat,

Now when I go through my movie folder and see older rips I cringe (480P movies that are 6GB, 1080P movies that are 20GB...hell I think Gone With The Wind 1080P is something like 35GB...what was I thinking!)
 
westrock2000 said:
I was very hesitant at first because I just couldn't believe that a 1080p live action film could be 14GB, but a 1080p animation could be 4GB. So I assumed it was messed up. But I did some viewing and I came to the conclusion that it really does know what it's doing. You'll get anomalies here and there, like films with a lot of night shots AND a lot of film grain...those will be fat,

Now when I go through my movie folder and see older rips I cringe (480P movies that are 6GB, 1080P movies that are 20GB...hell I think Gone With The Wind 1080P is something like 35GB...what was I thinking!)
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HD version of gone with the wind, indeed what were you thinking? ;)
 
westrock2000 said:
I was very hesitant at first because I just couldn't believe that a 1080p live action film could be 14GB, but a 1080p animation could be 4GB. So I assumed it was messed up. But I did some viewing and I came to the conclusion that it really does know what it's doing. You'll get anomalies here and there, like films with a lot of night shots AND a lot of film grain...those will be fat,

Now when I go through my movie folder and see older rips I cringe (480P movies that are 6GB, 1080P movies that are 20GB...hell I think Gone With The Wind 1080P is something like 35GB...what was I thinking!)
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Yeah, I had to do a lot of testing before I was satisfied, but it really does work well :D
 
I'd REALLY like to know why Netflix is handicapping pc-users and certain web browsers now?

I mean not only do we miss out on surround sound (which is capable on pc's and has been for decades) but they also do not allow 1080p playback on Chrome, Firefox, etc. Only on IE/Edge/Safari.

It just seems really really fishy, there's no way in hell you're telling me firefox/chrome aren't capable of 1080p, hell they can do 4k on youtube's html5 player.
 
I started a response here but it turned into a blog.

tl;dr
If they do a test encode using CRF then they will have a good approximation for bitrate. My guess is that they will "cap" the maximum bitrate but will reencode content that is overshooting bitrate so badly it went plaid.

For clarity, Variable Bit Rate has nothing to do with delivering different bitrates. The term Multi Bit Rate (MBR) is what is used when the client (HLS and DASH) or server (Silverlight) detect that there is now more or less bandwidth available and move to a completely different stream.

If you are delivering content that is segmented or sent in "chunks" you want to have them all about the same size. Streaming media using CRF or some implementations of VBR will cause the network bandwidth detection logic to fall down and it will feel like back in the day when RealPlayer was buffering. Yes, I worked at RealNetworks and supported their Helix Streaming Media Server. RealVideo is only popular in China.
 
Draax said:
I just read that Bell is going to offer Netflix as a channel on Bell Fibe.
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How can you offer Netflix has a channel? Maybe it'll be integrated into their boxes like on TVs and DVD players but a channel wouldn't work. That's one way communications.
 
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