Apple TV HD quality??

[GregA]

I think that before HD content over the internet can become common place faster internet connections will either have to be the norm or people will have to get used to starting the download before going to bed or work to watch later.

Agreed. The net isn't up to it yet.

I hope that Apple, when it starts working with HD, helps local ISPs cache information to minimise strain on the internet in general, as well as lowering cost for the ISP and for Apple. And if Apple uses peer-to-peer to aid the speed, hopefully they'll encourage local peering groups rather than peer to anywhere on the net.

edit:
The wait time for downloads is why I'd hoped AppleTV would work as a DVR.
Using a DVR forms new habits - you look ahead a couple of days and select what you want recorded when it airs (to watch later). This habit dovetails nicely with selecting movies you'd like to download (to watch later).

 

[Alphy]

Great thread, thumbs up.

I'm currently converting episodes of The Office which I capped @ 720p and now am running them through Videoara's Apple TV converter. I have bit rate set at 8192, which is a bit high. Not sure if she'll play it back. May try another encode @ 5120 and see how that looks.

Uhm, also; what do I do to get files that are bigger than 4GB to play back on ATV? I've read that it's possible to watch files that are bigger than 4GB, and I've also read that there is some sort of limitation. What's the deal w/that?

 

[GregA]

what do I do to get files that are bigger than 4GB to play back on ATV? I've read that it's possible to watch files that are bigger than 4GB, and I've also read that there is some sort of limitation. What's the deal w/that?

I read somewhere that they won't stream. They will sync.

Hope it helps.

 

[droz]

Bitrates

I believe the comments about ATV not supporting bitrates greater than 5Mbps are correct. Elgato has a comment on their website regarding the latest software update in support of ATV that indicates they had to pull back on full HD encoding (1280x720 @60fps) because the bitrates were too high. The max possible in their estimation is 960x540 @30fps and 5Mbps. This is very disappointing and is exactly why i'm looking to get a mac mini instead. This version of ATV just isn't cutting it. I expect we'll see indications of that in next week's earnings announcement. Maybe it will get them off their arses so as to develop ATV 2.0. I'm a huge fan of the concept and it has great potential, but mac mini is still kicking it's butt at this point. I expect Apple knows this, thus explaining the lack of updates to the macmini (still not running a core 2 duo? come on!)

 

[JAT]

HD-DVD/Blu-ray both are compressed video (although I think technically they do support uncompressed, raw HD video). What we're really talking about here is transcoding a video into a new format. Meaning compressed -> compressed in a different format. Which does result in a loss of quality.

No, neither of them support uncompressed raw HD video. HD video as used on HDDVD, BD, and your local TV network is compressed. To the tune of 52x compression.

 

[GregA]

HD video as used on HDDVD, BD, and your local TV network is compressed. To the tune of 52x compression.

Yes they're all compressed, but to different degrees. Higher bitrate will be higher quality - though at some point extra bits are irrelevant (slow scenes work perfectly at slower bitrates)

-BluRay compresses at up to 40Mbit/sec
-HD compresses at up to 30Mbit/sec
-AppleTV compresses at up to 5Mbit/sec
-HDTV ... usually uses MPEG2 at about 13Mbit/sec, h264 would be 5 or 6Mbit/sec.
-x264 downloads on the net look to be about 3.5Mbps - I haven't got any experience with them (seriously!).

Apple's HD samples look good, probably related to be 720p24 (gets some colour stepping with some fast moving scenes I've watched). If they wanted to show 1080i60 they'd need higher bandwidth.

 

[pilotError]

I hope that Apple, when it starts working with HD, helps local ISPs cache information to minimise strain on the internet in general, as well as lowering cost for the ISP and for Apple. And if Apple uses peer-to-peer to aid the speed, hopefully they'll encourage local peering groups rather than peer to anywhere on the net.

I was thinking that they would partner with Google on some of this. Google certainly has the data centers / bandwidth to deal with it, but I suspect that its just the content providers clinging to their DVD's.

It wouldn't be unreasonable to throw a Gigabit Switch in Airport Extreme and a Gigabit port on the back of an Apple TV to support full High Def. It may require the unit to have more memory and a larger disk cache though.

Not really reasonable for the Mass market just yet. I still think they are in learning mode with the early adopters.

 

[GregA]

I was thinking that they would partner with Google on some of this. Google certainly has the data centers / bandwidth to deal with it, but I suspect that its just the content providers clinging to their DVD's.

That doesn't solve the problem of local caching and local peering - it doesn't take the pressure off the Internet backbone itself.

Still, maybe Google has similar goals, especially for youtube.

I still think they are in learning mode with the early adopters.

Very true. The current AppleTV is a good start, still much to learn.

 

[zeroaxs]

go watch the Technology Evangelist Podcast

Yes they're all compressed, but to different degrees. Higher bitrate will be higher quality - though at some point extra bits are irrelevant (slow scenes work perfectly at slower bitrates)

.....

Apple's HD samples look good, probably related to be 720p24 (gets some colour stepping with some fast moving scenes I've watched). If they wanted to show 1080i60 they'd need higher bandwidth.

Sounds like some of you need to go watch the latest Technology Evangelist podcast from iTunes that has information about the differences between the different HD video types. 1080i isn't somehow "better" than 720p. Why would they want to show 1080i? You're effectively only getting a 540p signal with enhanced horizontal definition that ALSO gives you smearing effects...

I don't understand the big deal with 1080i. Now p... that's a different story.

 

[Scarpad]

Apple TV plays files bigger than 4gb. I've played 7gb on it... But, I can't stream it, only sync.

Well that makes sense, if Itunes does go for a rental model for HD material then most likely you'll have to Sync the movie to the internal HD for playing, which means 3 to 4 movies at most. I have'nt synced anything yet not even photos,

 

[GregA]

Sounds like some of you need to go watch the latest Technology Evangelist podcast from iTunes that has information about the differences between the different HD video types. 1080i isn't somehow "better" than 720p. Why would they want to show 1080i? You're effectively only getting a 540p signal with enhanced horizontal definition that ALSO gives you smearing effects...

I don't understand the big deal with 1080i. Now p... that's a different story.

If film is converted to 1080i60, is can be de-interlaced with no loss of quality. It becomes 1080p24. That is only possible if it's filmed as 24 frames (which is current practice), as it can then merge the odd and even lines from the same original frame.

For video 1080i recordings you are absolutely correct. I'd rather have 720p.

See: http://en.wikipedia.org/wiki/1080p#Availability

Note: I have no idea if 1080i50 (pal) can be de-interlaced the same way... just can't find anything on it.

 

[ftaok]

Note: I have no idea if 1080i50 (pal) can be de-interlaced the same way... just can't find anything on it.

I read somewhere that interlaced PAL can be deinterlaced to 25p. When watching material originally filmed in 24p, 25p runs slightly faster, around 4%.

I don't know if it's true, as it seems awfully strange. If they did that in the USA, someone would want to sue for damages.

ft

 

[GregA]

I read somewhere that interlaced PAL can be deinterlaced to 25p. When watching material originally filmed in 24p, 25p runs slightly faster, around 4%.

I've read the same. In fact for one show I noticed a change in pitch of the actors voices, though that is normally corrected for.

I'm guessing that TVs which reconstruct 24p from PAL can't undo the 'sped up' method, since they can't change the speed of the signal they're receiving. The German Pioneer website implies they can reconstruct 24p though...

The other method of converting to PAL is to copy every 24th frame. A reconstruction would de-interlace the frames, then look for the one which is doubled (or half de-interlace, look for the field which is doubled and remove that, then continue de-interlace)

Anyway, for now that's why our AppleTV is set to 720p60. The TV reconstructs 24p and switches to 72Hz and refreshes each frame 3 times. Unfortunately the TV isn't smart enough to automatically detect 50/60Hz and use different methods, "purecinema" handles one or the other only. So DVDs may suffer.