The Deinterlacing Done by Online Video Services

[jmac698]

I thought this was an interesting analysis. If you want to know which video service has the best video quality, read here.

All online streaming services and video stores provide progressive video, so they must deinterlace the data first. This article compares the deinterlacing strategies of Apple iTunes, Netflix, Microsoft Zune, Amazon VoD and Hulu by comparing their respective encodings of a Futurama episode.

http://www.pagetable.com/?p=484

[Gser]

I wonder how youtube compares.

[CruNcher]

he compared the quality of encodes provided for online distribution not what happens on the system when a user uploads something, you cant compare youtube like those distribution platforms yet ;)

His compare actually shows that Microsoft and their Framework (though you dunno if everything was fully automated or done by a Microsoft guy or some other 3rd party involved, that is pure speculation by the reviewer) did best with the supplied source from FOX preparing it for VC-1 distribution in the Zune Shop.

It's more a "How much resources are put into Quality @ different companies preparing digital distribution of Studio Source Material" ;)

Microsoft is known to care about Quality when preparing Studio Source for their Device Ecosystem same as Sony :)

[TheSkiller]

Would be nice if platforms like YouTube started supporting the storage and correct display of interlaced video instead of offering the super-duper-awesome FullHD 1080p (at way too low bitrate for this resolution) which nobody needs. I don't consider "progressive only" on video platforms a feature but rather a limitation. What's so hard about doing some basic bob()-like deinterlace during playback? Even GPUs are able to deinterlace these days so...

That article seems a bit inaccurate to me, as if someone wrote it who knows about some things but not the whole story, it starts with the very first sentence. Since when is broadcast not interlaced anymore? And "In the days of CRT monitors" sounds like we're in the year 2025. :rolleyes:

[CruNcher]

TheSkiller they wont do it they will always deinterlace and this is pretty understandable because they want to reach as much user as possible with 1 Quality and not different qualities based on the Deinterlacer on the Client side. The Experience should be always the same it's debatable if it's the right way (especially reaching enough user should be these days no problem that have fast and good quality deinterlacing hardware client side) or do you think they like to invest all the time the Deinterlacing of uploaded sources they surely would like to avoid it but they fear to loose user (losing user is something to be avoided @ all costs for maximum advertising profits) i guess also based on the problems it could bring on different hardware, drivers ect (another source of bugs, support issues) and you surely try to avoid these problematics and its Google worth it to Deinterlace everything that comes into the system (minimizing risk, of unhappy user experience and in the end as mentioned before advertising loses) :)

And we didn't spoke about the HTML5 problems yet and trying to get 2 different systems in sync :P

And to be true i would do it the same way ;)

[TheSkiller]

YouTube already does offer several quality modes, as I'm sure you know. So why not add for example 480i (29.97 interlaced) in addition to the already present 480p (29.97 deinterlaced)?

The quality of playback wouldn't suffer by adding interlace support either way because the deinterlacing they do by themselves is a joke anyway.

[CruNcher]

What you say would increase the costs again (they chose this as their common denominator, also the quality of the Deinterlacing is calculated on the costs it triggers on the system) They constantly improving and if they find a way to provide a better deinterlacing without highering the overall costs to much (you have to think in very big scales here in terms of content bandwith, energy, infrastructure ect) they surely will do it.

[TheSkiller]

Not if they dropped the 1080p. ;)
Honestly who watches videos in 1080p on YouTube? Most Laptops and older computers cannot handle it and often this exceeds the desktop resolution anyway. It's just my opinion but I think that whole 1080p thing on YouTube sucks up lots of valuable space and traffic that could be used otherwise.

Edit: Even if they improve their deinterlacing to the quality of QTGMC (which will never happen ;)) the deinterlacing still means that videos are limited to their "base" frame rate. With 480i you would have 59.94 fields per second. I image there are many places where this would make sense where you are currently limited to hard-deinterlaced 29.97.
Of course there's the option to do 59.94 progressive but that might be overkill again, like 1080p.

[CruNcher]

That's why Youtube uses the Bandwith which is also part of the decoding complexity to reach enough user ;) the better the guys do the calculations @ look @ the numbers their telemetry shows the better they gonna optimize it though they also have to take other factors into account as of bandwith availability in different regions of the world (the allways very controversial geo policies,DMCA system content protection) and so on Youtube is a very complex overall system and surely there are errors made in some decissions but thats pretty normal the decission for 1080p though is based on the need for it you cant be successful without it anymore if you like it or not :) tell a advertiser you only have SD resolution and i guess he will lough out loud ;)

I don't wanna know where a tech guy for Youtube has to go through when proposing a new idea but i guess it will take some time to go through all the layers their till the impact of the change is carefully calculated first including a test phase with new telemetry :D

Look @ Stage 6 for example it was pretty High in Quality and where is it now ;)

[2Bdecided]

Would be nice if platforms like YouTube started supporting the storage and correct display of interlaced videoI think that would be unworkable - you want flash player to deinterlace? You want to trust that the PC videocard deinterlaces?!

However, support of 50p and 60p would be most welcome. Then we could deinterlace ourselves and retain smooth motion.


As for the original link - think how much we love this stuff in the UK. Streaming services, using the US masters for many films, show us doubly or tripply-bad motion judder (30p from 24p - sometimes output as 25p or 50i with the worst possible choice of frame removal/addition) - and this in a country where we've never seen 3-2 pulldown judder on our screens (except for BluRay on TVs which can't do 24p) because all SD films have simple 2-2 pull down.

It amazes me that people don't send 24p as 24p - or maybe 25p over here - and let the device do the best it can with it.

Cheers,
David.