Apple TV version 2 and HD - the facts versus other HD formats

[notabadname]

This is part of another post I made, but felt it would probably be good info for its own thread, and helping people understand Apple TV's foray into HD, and how its performance stacks up against other HD formats/sources.

Blu-ray's max data transfer rate (video/audio) is 54.0 Mbps
HD-DVD is 36.55 Mbps.

Max storage capacities:
Blu-ray 50 GB
HD DVD 30 GB

While putting these numbers out, it is important to note the significant difference in the new Apple TV's version of HD and the Disc formats listed above.

Compare the disc data rates to Apple TV's data rates of 3 Mbps video and 160 Kbps audio. (also 720p versus 1080p which equals roughly 1 million pixels versus 2.1 million pixels). By comparison, for cable and network TV, the ATSC HD specification calls for at least 19.25 Mbps data rate for high-definition terrestrial transmissions.

Note the audio bit rate (from Apple's web site) specs for Apple TV doesn't even match iTunes Plus bit rate of 256 kbps. Yet that bit rate of 160 kbps for Apple TV is going to have to carry Dolby Digital 5.1. There is a lot of compression going on for 5.1 channels compared to the 128 kbps of even standard iTunes music for two (stereo) channels.

So you can see that HD DVD and Blu-ray Disc have at least twice the bandwidth of HD TV that you will see on Broadcast or Cable TV (which is why you don't see any "macro-blocking" or artifacts on action scenes or sports on HD Discs, but you do on Cable sports or action movies. And Cable has 6 times the data rate of Apple TV (and HD disks have at least 12 times the data of Apple TV HD).

Another clue is that the HD movie files from Apple will be about 4Gb each, which is the size of a current (shorter) standard Def movie on DVD (up to an 8.6 GB file file size). Compare that to the max movie/file size of the HD formats above.

Bottom line, Apple TV is a neat idea, but its quality will suffer from heavy compression when compared to HD-DVD and Blu-ray, and even pale in comparison to Cable or Satellite. Certainly worth consideration in purchase decisions when an HD player (of either format - HD DVD or Blu-ray) can be had for a similar price now. Just like the way iTunes Plus upped the sound quality of songs, there is going to need to be a "plusing" of Apple's HD movie file size if it is going to get serious attention in a very competitive HD market place. At least, in my opinion.

[Yuiichi]

Great write-up, notabadname.

One reason I can see for Apple wanting to lower the "standard" for their HD content would be this renting model they have going. Current tests have SD and HD movies loading within 5 to 10 seconds after renting them, which is excellent over models such as Xbox Live Marketplace movies, which often have you wait for a much longer time.

Without compression, do you think they could deliver the same service?

Also - I have another question about HD. Currently, I only have some HD channels through cable (as I don't have an Blu-Ray or HD DVD player), but I really don't notice all that much of a difference from SD TV. It's true that I'm not watching it in "true" 1080p, but I think I would notice some difference. Is the difference between SD and anything below 1080p really that negligible for cable? Or would 720p give me better performance than the 1080i that it's currently running at?

[notabadname]

You should notice a significant difference from SD to either 720p or 1080i. Make sure the particular show you are viewing is in HD. There are a lot of standard def shows running on "HD" channels still. Especially the major networks. Then make sure you have at least a component video connection from your cable box to your TV. If your cable box doesn't have at least a component video output, then it is not an HD box, even if you are paying for HD. If you are using an RCA jack or S Video connection on an HD box, you really wont see much of a difference. Component or HDMI (best) will give you the difference. For 1080p, HDMI is actually required but Cable or Satellite do not offer 1080p programing. Component will only pass 720p or 1080i.

X-Box software normally runs as 720p for example, that is HD and looks excellent even on my 70 inch screen. So yes, you should definitely see a difference between standard def and Cable or Sat 720p/1080i. If you have a screen that is 720p (it may say it has a resolution of 720 up to 768) then I would use 720p output option from your box. If you have a 1080p capable TV, then use the 1080i output option.

As for compression, a larger file will certainly take longer, and delay the time before you can start watching. For good broadband, a 4 GB file would probably take about 22 minutes or more at 3 mbps. So once you got the file started, the rate of play, probably would not exceed the rate of download. If you doubled the file size for the same movie, you would need to wait that 22 minutes (at least) to start playing so that your movie wouldn't "run out" during play as it completed the download. People with slower (yet common service of say 1.5 Mbps, are going to have to wait that half hour before play even for a 4 Gb file. So it definitely had to be a factor in Apple's consideration. I'm sure their server size and bandwidth capabilities for sending these files out is a limiter too. Also their entry Apple TV is only 40 GB, not even the size of one Blu-ray disc at up to 50 GB (amazing actually). Larger file sizes (say double) would only let you have 8 movies max, with no other TV shows, etc considered.

[Yuiichi]

I have my cable box hooked up via component. It does have the option to be connected via HDMI, but it's an older spec and isn't as good as the component output. I'm also sure that the shows are in HD - SD TV is in a 4:3 aspect ratio whereas these shows play at 16:9 to fill my TV. I'm pretty sure that's a good method of telling me which is in HD and which is not.

The only trouble I have with seeing a "difference" in my Xbox is that I've never used it with the composite video. Sure, it looks really great in 720p (on that same TV), but does it look good because of HD or because the console itself is powerful? Games look really great on PCs too, and they don't have to be playing in an HD resolution.

HD is nice and all, but I haven't really seen anything that blows me away.

[notabadname]

You should see a difference as noticeable as your 360. Shows such as 2 and a 1/2 Men or the Tonight Show (in HD) are as dramatic on my screen as the 360. Very detailed, with skin pores and individual hairs that you never see in SD. Sports are the same way. The NFL playoff games are incredible, with individual blades of grass discernible.

A computer came on a computer monitor is essentially HD. Unless you are on an old monitor at 800 x 600 (which is still higher resolution then SD (SD DVD is 480 lines vert), then you are likely at least 1024 x 728, and that is HD. A 20 in monitor is normally 1680 x 1050. 1050 vert is basically equal to the Highest "Full HD" at 1080 vert.

[notabadname]

Here is a comparison, frame for frame of Standard Def versus High Def. The stills are untouched of Superman Returns, simulcast on HBO HD and HBO standard. Note the details in the sky above the horizon, details in the ground, the house to the left shows siding and dirt in HD. Note the railing on the porch in HD. Plus notice the difference in color gamut. Also notice the crispness of edges and borders, like the green trim on the white house. One looks like a normal photograph that I took outside, the other looks soft, and very much like a still from a TV. At least in my opinion, the difference in these is quite dramatic.

Camera settings are identical, with a Nikon D70.

Flickr Photo Download: Superman Returns SD frame capture

Flickr Photo Download: Superman Returns HD frame capture

[Yuiichi]

Yeah, I definitely see the difference in those. I've also seen stills from the LOTR HD editions that are being planned compared to the LOTR SD editions (of which, I own the standard and special edition DVDs) and the difference is quite noticeable.

I don't think that the difference on normal cable stations are as dramatic, just due to the bandwidth that you stated of cable. Would you agree, or am I still just not seeing the difference?

[notabadname]

I think for whatever reason, you just aren't seeing it. I have just as dramatic results on regular broadcast TV. I have both the standard def networks and the HD versions. I have switched back and forth between simulcasts of 2 1/2 Men, and also Letterman to show friends who haven't made the switch to HD. They always find the difference to be very impressive. And I know my Direct TV bandwidth should be comparable to your cable.

[Yuiichi]

I just watched a few minutes of Tennis in HD (it was the only thing I could flip between HD and SD) and although I could tell something looked better (other than the fact that the 16:9 looks a whole lot better than the 4:3 stretched), I couldn't tell what. The colours looked a little more vibrant I think, but I couldn't see anything really drastic when they were playing. Close ups looked more detailed too.

[notabadname]

smaller screen sizes will make the difference less obvious too. Just like a 3 mega pixel and a 6 mega pixel version of the identical image printed to a 4x6 print will be pretty hard to tell apart. Print those both to an 8 x 10 and the difference will be come apparent. Are you on a 32 inch screen or smaller?

Also, are you sure you are connected by component video (has three plugs on either end)? You could always try HDMI, which is the best connection. Even if you have an older HDMI TV (meaning pre version 1.3), it will still give the best possible picture to use HDMI as compared to component. HDMI is digital, component is the highest quality analog. If you have a 1080p TV, then the older HDMI will not work with 1080p, but neither will component video. And cable is not 1080p, so it wouldn't hurt your signal anyway.