Apple TV resolutions

Question

I've read that the Apple TV supports HD 720p/1080i resolution. But movies for sale on iTunes are 480p, right? There are presently no HD movies available for sale on the iTunes Store. Is that correct?
So, does the Apple TV, over component video connection, upscale 480p iTunes Store movies to 720p or 1080i? Or is it straight 480p? (As a pre-Apple TV purchase test, I downloaded what I'm assuming is a standard-def TV show from iTunes in widescreen (the "Raines" pilot) and played it via the iPod composite audio/video output to my HDTV, and frankly, I was pretty much blown away by the quality. And I'm 99% sure there's no way the iPod video upscales over composite. So it's not a deal-breaker; I'd just like to know if the Apple TV upscales over component connections.)
And, if I were to download some of the sample HD content from Apple, like say the BBC stuff, would it play at 720p or 1080i on the Apple TV, or will it only play at 480p?
Last question, when TV shows first became available on the iTunes Store there were only sold at iPod video resolution, like 320x240 or something like that. Then when they started selling movies, they started selling them and new TV shows at H.264 640x480 -- 480p. Did they go back to all the old TV shows they sell and upgrade those to H.264 640x480, 480p, too, or leave them at the old iPod video resolution? And if they did not, and there's mixed resolution content on the Store, how can I tell if what I'm buying is 480p or the old, lower iPod video resolution -- before I buy it.

Answer 1

I've read that the Apple TV supports HD 720p/1080i resolution.TV supports input file formats up to 720p24/25 (1280 x 720 @ 23.98/24 fps NTSC or 25 fps PAL). On the other hand, it can output various signals compatible with the specific HDTV and interface to which it is connected. E.g., most HDTVs may offer 1080i (1920 x 1080 interlaced), 720p (1280 x 720 progressive), 480p (854 x 480 progressive), or 480i (640 x 480 interlaced) settings via the HDMI or component interface, as well as, 576p (1024 x 576 progressive) or 576i depending on the TV. If connected to a PC DVI interface, a whole new range of PC compatible formats may also be available. It all depends on the TV and the interface used.
But movies for sale on iTunes are 480p, right?No, I believe you are limited to "Baseline" and "LC" H.264 content which limits limits dimension to within 640 x 480 depending on aspect ratio. I have never purchased any files but have downloaded some of the "free" samples encoded as 640 x 480 and 320 x 180 files.
There are presently no HD movies available for sale on the iTunes Store. Is that correct?As far as I know this is correct. (As I say, I am not what you might call a "regular ITMS customer.")
So, does the Apple TV, over component video connection, upscale 480p iTunes Store movies to 720p or 1080i? Or is it straight 480p?Scaling depends on your HDTV, your TV output settings, and the format of the file itself. Generally speaking, a 16:9 file will be displayed at full screen dimension on a "widescreen" HDTV. A 2.35:1 movie will be displayed "letterboxed" top and bottom. And, a 4:3 aspect ratio content will be display "pillared" left and right. If your HDTV has a native resolution of 1920 x 1080 and your TV is set to output at 1080i and your input file is 720p, then yes, the movie will be upscaled to match your HDTV. On the other hand, if your HDTV has a 1280 x 720 native resolution and your TV is set for 720p output, then no scaling is required. On the other hand, either of these HDTVs playing the 720p input file via the 480p TV setting would downscale playback for an 854 x 480 or equivalent screen display. In addition, depending on your particular TV model and mode, various "scaling effects" may also be available. These may range form horizontal fill to justified horizontal fills to zooms.
(As a pre-Apple TV purchase test, I downloaded what I'm assuming is a standard-def TV show from iTunes in widescreen (the "Raines" pilot) and played it via the iPod composite audio/video output to my HDTV, and frankly, I was pretty much blown away by the quality.This scaling was done by the HDTV alone. Some models have excellent scalers built in. Others less so. On mine the TV scaler is better than the one in the TV, so I see quite a bit of improvement watching the same file via TV as opposed to my iPod via the TV's composite input.
And I'm 99% sure there's no way the iPod video upscales over composite.No, as indicated above, the scaling here was performed by your HDTV and not the iPod.
And, if I were to download some of the sample HD content from Apple, like say the BBC stuff, would it play at 720p or 1080i on the Apple TV, or will it only play at 480p?As indicated above, it will play at the "scaled" resolution you select as the TV resolution setting and as is negotiated/avialable on your particular HDTV. Be advised, however, that if the input file is encoded at greater than 720p or has a frame rate greater than 24/25 fps at 1280 x 720 encode dimensions, or has a video data rate well in excess of 5.0 Mbps, it may not be playback compatible with the TV device without re-conversion.
Did they go back to all the old TV shows they sell and upgrade those to H.264 640x480, 480p, too, or leave them at the old iPod video resolution? And if they did not, and there's mixed resolution content on the Store, how can I tell if what I'm buying is 480p or the old, lower iPod video resolution -- before I buy it.Based on the "free" samples, I would assume there is still some "mixed" content out there. However, it should be relatively easy to determined what content is which. One way would be to simply play the trailer/preview and see what it looks like. Another, possibly better method is to simply compare the running time against the file size. Since the 480i (640 x 480) "Low Complexity" files are encoded at roughly twice the video data rate of the older "Baseline" H.264 files, it is esay to tell them apart. For instance an average 2-hour "LC" movie will run between 1.2 and 1.6 GBs in file size. A "Baseline" (320 x 240) version of the same file would likely only be 600-800 MBs in size.