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Comment by aeturnum | Hacker News Reader

I don't really know what people "generally" think of Netflix encoding, but my experience is that it's Very Bad. It's a combination of factors:

- Netflix will only send you "high quality" (over 720p) streams on certain browsers (IE on windows, Safari on OSX, ???? on Linux) that support Encrypted Media Extensions.

- Netflix also auto-scales the quality they are sending based on their understanding of your connection.

- Also apparently they do per-title re-encoding passes.

This all combines, in my experience, to on average the worst streaming quality overall and also the most opaque. There are debug modes you can enable to see some of this, but generally it's very hard to tell what quality you are looking at and what is preventing you from getting a nicer quality. I also find that Netflix's "low profile" content (i.e. not max quality) looks bad - i.e. the 720p stream looks quite bad in addition to being low resolution.

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> Netflix will only send you "high quality" streams on certain browsers [...] that support Encrypted Media Extensions.

They won't send you anything at all unless you have EME, coupled to a supported DRM engine. Getting >1080p requires a "more secure" DRM engine (e.g. Widevine L1, PlayReady SL3000)

> - Netflix will only send you "high quality" (over 720p) streams on certain browsers (IE on windows, Safari on OSX, ???? on Linux) that support Encrypted Media Extensions.

It's not only netflix that does this, all of the streaming services do (though some of them limit to 1080p instead of 720p).

Such an utterly pointless anti-piracy measure... every show ends up on torrents in 4k regardless, only serves to punish those actually paying for the service.

I believe it's rooted in agreements that content producers (including Netflix I am sure) insist on for distributing media. My impression is that all anti-piracy measures are intended to "just" extend the exclusivity period for official sources for that media. So almost anything you can do to delay high quality rips appearing will be worthwhile for the company financially.

Torrents for popular movies and tv shows tend to appear within hours (in good quality even) so not sure how successful that attempt at delaying is

Netflix 4k titles certainly don't. It's often weeks at this point for web-dls.

It's similar with YouTube's premium content, i.e. DRM-protected films or series available for rent or purchase on YouTube. It plays at a maximum of 480P on most desktop browsers, including Google's own Chrome for Windows. (Disclaimer: I haven't checked this recently, I'm assuming the situation hasn't improved.)

* https://support.google.com/youtube/answer/3306741

* https://support.google.com/youtube/thread/89050028/my-movie-...

You are talking about PC browsers, but I do not think they are the main target of Netflix nowadays.

They would be much more concerned about the quality on their app on smartphones, tablets and smart TVs.

I thought the same, but it turns out I have quite a number of friends (especially younger, who are sharing apartments with flatmates etc.) who don't have a TV or tablet, and who will just sit on their bed or couch with a laptop for netflix and such. This is totally anecdotal of course, but I do feel like it might be the device stats are quite different from what we might expect.

They are, but only in that you would be surprised at how tiny the PC usage is to most online video streamers, it's even smaller than anyone would expect.

Because of this quality issue, I always wondered how people who rip Netflix content handle this, since they often offer 2160p Dolby Atmos versions of movies or even TV show episodes for download.

How do they maintain the quality long enough to rip the content? When I used Netflix years ago, I could barely keep a constant 1080p stream at times.

I suspect that what you receive is determined client-side in software, and with some reverse engineering, you could force it to send you whatever quality you want (as long as your subscription allows for that quality level).

They use HDCP strippers, devices which can strip protections from the hdmi signal, at which point they can feed it into an capture card to reencode.

I don't think they reencode it. They've found a way to download it directly. I think they have found a way to extract the keys.

Source? It's hard to see how they actually did it when all you have is a .mkv file, but in rare cases I've noticed ui elements/quality drops that was indicative of being ripped via capture cards. Of course, that doesn't mean all rips are done this way, but it's pretty hard to tell the difference between a rip done via capture card done perfectly, and a rip where the underlying stream was decrypted.

I have read a few people commenting that that's how it is done. I read a very good comment once here on hn that described extracting keys from insecure devices (might have been TVs, or possibly an older Android device?), although I can't find the comment now.

Also they often contain every subtitle and audio track (often 40 subtitle tracks!), which would be either a lot of work or not possible at all if they couldn't extract the stream properly. I suppose they might be able to get those from the low quality unencrypted streams but it just seems implausible.

They release shows pretty much immediately as soon as they are on netflix, don't they?

It seems improbable to me that they are systematically recording and reencoding every show manually, although I guess it could be possible in theory.

A friend of a friend tells me that they've never seen UI elements or quality drops on any scene rips.

All signs seem to point to the encryption being broken in my opinion.

>Also they often contain every subtitle and audio track (often 40 subtitle tracks!), which would be either a lot of work or not possible at all if they couldn't extract the stream properly.

Are subtitle tracks even encrypted? Unlike video, there's no secure path (eg. HDCP) for subtitle (or even audio) tracks, so they're presumably trivial to rip.

If you were ripping via HDMI you'd still need to sync them up though. Not very difficult but tedious. I still believe they're using leaked or hacked keys.

e.g. https://github.com/medvm/widevine_keys

I believe this specific method is outdated, but my understanding is that current methods also bypass drm instead of using screen capture.

That gets you L3 keys, which only provide sub-hd resolutions.

There are devices out there with vulnerable TEEs (trusted execution environments), where DRM operations commonly happen. You can then extract L1 keys from those environments - for example with the Nexus 6[0] NVIDIA Shield[1].

[0] https://googleprojectzero.blogspot.com/2017/07/trust-issues-...

[1] https://nvidia.custhelp.com/app/answers/detail/a_id/4682/~/s...

Those keys were downgraded to Level 3 many years ago.

I think the OP's question was maintaining the higher quality stream, not the act of ripping.

That doesn't seem hard to pull off. Just record the stream multiple times and splice/replace the low quality bits.

The FTP topsite scene is extremely competitive and anyone doing multiple rips to splice together would lose the race to leak the show.

The best WEB-DL groups are internal P2P - FLUX (HDB) and NTb (BTN).

They both (afaik) do hybrid releases by taking e.g. audio or DV metadata from one service and merging it with another source.

Funnily enough, even for UHD remuxes, P2P groups are top-tier (like Wildcat and Framestor).

Doesn’t work for Dolby content, unless there exists such specialty devices that can decode Dolby.

If they know what they're doing, they don't "rip", they use their own client to download the highest quality available directly from the CDN, then strip the DRM.

> Netflix also auto-scales the quality they are sending based on their understanding of your connection.

Netflix dropping to potato quality after a few minutes is infuriating. Refresh the browser and quality goes back up for a few minutes before it drops again. My wife often doesn’t notice it; it drives me nuts. My theory is that they try to save bandwidth by dropping quality after some time and hoping you don’t notice.

Probably because there's a significant number of people who just stream stuff constantly as background noise. The tyranny of the minority.

They should just have a setting the user can set to decide how much buffering vs quality they’re willing to tolerate

For whatever it’s worth, I’ve never had any problem with it.

I’ve got a bookshelf computer hooked up to a 52” 1080p screen in my living room, nothing fancy, and I’ve never noticed any issues at all with quality, or buffering times. I just open the video through the website in chrome, and play it, and it’s fine.

I think you will probably see a noticeable increase in quality if you install one of the "netflix 1080p" extensions[1].

[1] https://chromewebstore.google.com/search/netflix%20higher%20...

> Netflix also auto-scales the quality they are sending based on their understanding of your connection.

This is the future. You can multiply a pixel as many times as you want.

They really managed to squeeze the sound quality to a minimum.

I have a friend who genuinely thinks Dolby Digital Plus ripped from streaming services is higher quality than lossy DTS ripped from a DVD or Blu-ray. Insanity.

100% agree with all of your points

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