What he said.
--- In FairfieldLife@yahoogroups.com, Bhairitu wrote:
>
> I would have to review that. But there's a problem with speculating
> what Netflix does. As Barry would tell you, having worked for tech
> companies, it is often not *what* they are actually doing. But any
> programming just glancing at the article would as expected it would
> speculate that is basically data mining or maybe more correctly "data
> scraping."
>
> Netflix will post blog articles about their techniques. And I get to
> argue with people who claim they are still using these techniques some
3
> or 4 years after the blog article has been posted. Worse yet I get to
> argue with geeks about Netflix encoding methods. One ongoing argument
> is that my Sony BD is too old to use "adaptive streaming." Mostly
> Netflix does not have one file for each stream. Instead streams are
> broken up into each small files for MPEG-4 and those may be for HD as
> small as 1.2 MB each. They will have several of thees kinds of stream
> files at different resolution ranging from 240p to 1080p. If they
> detect some congestion between you and their server they will drop
down
> to a lower resolution stream just to catch up. In fact if you watch a
> movie on Netflix they often will use a 240p stream just to start for
> about 30 seconds. That's because at the start of most movies is a
bunch
> of studio and distributor logos so it doesn't matter. In the meantime
> they're able to buffer up to a minute of HD while your player shows
those.
>
> And that's for ONE kind of steam. Netflix admits they may have as
many
> as 120 different stream packages for each show. That's to handle the
> wide range of devices that Netflix can be viewed on. And it gets worse
> than that. The MPEG-4 example just makes it a little easier to
> understand. But the files don't have to be broken up into small files
> on the server. Silverlight which Netflix uses doesn't necessarily do
> that as I've played with Microsoft Expression which can be downloaded
> for free and will do up to 10 minutes of Silverlight encoding at
> different resolutions. Those are in VC-1 format though the paid pro
> version can do MPEG-4. Each resolution has only one file and an index
> manifest for seeking.
>
> Favored probably by the industry is the emerging HTML5 codec that
Google
> offers... for free. This is Webm which has the VP8 or VP9 codec from
the
> company Google bought. Those are like Silverlight singe files for
each
> resolution, video only. The audio file is separate. All these have a
> meta data or manifest that allows them to quickly seek the segment to
> send out. Chromecast is most likely using these for newer films.
>
> Where I get into an argument with the techies is that I have always
seen
> varying resolution on my supposedly non-adaptive (DASH) supported BD
> player. I have even told them that the Netflix app got updated at
least
> once. I also have done projects using Sony's SDKs and know how they
> handle MPEG-4 files. The player is probably about the same as on
their
> devices I have programmed. BTW, none of the people I am arguing with
> have EVER done that nor even shot, edited video let alone created
video
> players (I've had to create two of those).
>
> The reason Netflix won't tell you *what* they are actually doing is
tech
> is VERY dynamic. So what they did last year might be completely
redone
> this year. They keep upgrading their technology. They need to remain
> competitive. And when you work for a tech company you are bound by
NDAs
> which severely limit what you can say. So we don't exactly have
Netflix
> employees (who are probably lurking and laughing) drop in to post.
>
> So reverse engineering their suggestions technology might have led to
> gaffaws and grins down in Los Gatos.
