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JoeTheZombie
Nov 3, 2011, 11:04 AM
I understand the ATV2 maximum output is 720p. I also understand the unit can playback 1080p content; output internally down-sampled to 720p.

I've read various reports that when playback 1080p, there are studdering or buffering problems. All of these reports are from jailbroken devices running xmbc or plex. Some say they are resolved with updates, others still have the problem.

My question, will a stock ATV2 playback 1080p @ 720p with no performance issues? Will it show any kind of performance issues with 1080p content, or is the down-sampling silky smooth?



jmcgeejr
Nov 3, 2011, 11:40 AM
I understand the ATV2 maximum output is 720p. I also understand the unit can playback 1080p content; output internally down-sampled to 720p.

I've read various reports that when playback 1080p, there are studdering or buffering problems. All of these reports are from jailbroken devices running xmbc or plex. Some say they are resolved with updates, others still have the problem.

My question, will a stock ATV2 playback 1080p @ 720p with no performance issues? Will it show any kind of performance issues with 1080p content, or is the down-sampling silky smooth?

A few things, it really depends on the bitrate that the 1080p content is at. If it's high then forget it, if it's low it may be watchable but not ideal. The best way to watch 1080p on the atv2 in my opinion is to use plex, the media server as long as you have a decent desktop hosting it will transcode, I have done the 4Mbps 720p stream to my atv2 with high bitrate 1080p and it's smooth and doesnt look bad at all.

tbayrgs
Nov 3, 2011, 02:30 PM
I understand the ATV2 maximum output is 720p. I also understand the unit can playback 1080p content; output internally down-sampled to 720p.

I've read various reports that when playback 1080p, there are studdering or buffering problems. All of these reports are from jailbroken devices running xmbc or plex. Some say they are resolved with updates, others still have the problem.

My question, will a stock ATV2 playback 1080p @ 720p with no performance issues? Will it show any kind of performance issues with 1080p content, or is the down-sampling silky smooth?

I've played a handful of 1080p content on my unjailbroken :apple:TV2 with no stuttering issues (between 9-12 Mbit/s bitrates) but have had a few problems with repeated buffering. My guess (don't quote me on it as I have no specific expertise or proof) is that it's due to the file size of these movies. Specifically, movies where I've encountered this issue are have file sizes greater than the supposed 8 GB of RAM that the :apple:TV has and as it cannot buffer the entire film, the result is repeated buffering incidents. When this happens, i've noticed that the entire film (or as much as the :apple:TV2 can hold) has been buffered (gray bar extends all the way across the playback bar at the bottom of the screen). If I exit out to the menu and restart the movie, thus clearing out the buffer, the problem disappears--I just have to fast forward back to the point where I left off. Kind of a pain in the a$$ but manageable.

I now generally encode only select movies in 1080p for viewing on my Mini HTPC via PLEX and make another copy at 720p for viewing on our :apple:TV2s, iPads and iPhones. I've got plenty of room on my external HDDs and my Mini Server screams along nicely doing these encodes so not too big a deal.