Apple TV - Video Stutter.

[jajohns8]

The Official Apple support page thread for this is up to 4 pages now. (just google 'Apple TV 2 video stutter' to find it. It's the top listing.)

One of the main things people are recommending is to fill out the Apple TV Feedback form, located here:

http://www.apple.com/feedback/appletv.html

The thread mentioned above also has the link.

Hopefully we will see a resolution to this through a firmware update.

 

[badweasel]

clarify

Before finding this thread I had already started another one at:

https://forums.macrumors.com/threads/1034558/

Then hipnetic was kind enough to direct me over here. If you have not seen my comments over there you should give it a read also.

There are different kinds of playback problems and we shouldn't get them confused. One of my friends had issues with a total video freeze lasting for several seconds and then it catching up. He fixed that by doing a reset all. I never had this problem.

Then there can be problems introduced by using different tv digital filters (a setting in some tv's) which do motion smoothing and things like that. However, typically these types of problems would be completely repeatable given the same source material. Play a movie twice and you should see the same types of artifacts each time you play it and in the same scenes in the movie each time. Repeatable. Oh.. and also I would expect this type of problem to show up no matter if you're playing off the old or new apple tv. Our problem is on the new but not on the old.

A problem with a handbreak encode might be repeatable and might be intermittent depending on why. If you set the bit rate slightly too high you could see a dropped frame anywhere, back up play again and it might be ok. This theoretically could drop a frame even if the movie is fully cached, say if the h264 decoder or the bus from the cache just choked on the bit rate. A problem like that COULD be intermittent but more likely would be repeatable. Since the two atv's are different hardware and software, this could be an issue that plays different on different hardware. Still I suspect something else (other than handbreak) since movies purchased from apple exhibit this problem.

I suspect it can be fixed with an AppleTV software update.. which we think will be coming in early november when apple releases iOS 4.2 for iPad.

hipnetic.. are you seeing any skipping on netflix? I've always thought netflix streaming was crap anyway but have not tried it in a while, so not sure you'd notice a difference. I suspect that the netflix player is completely different code, so maybe it doesn't have the problem.

 

[hipnetic]

Hopefully a mod will merge the two threads, since there's some very good information in that other thread now (though there's also too many posts which unfortunate/unnecessary arguing as to whether the problem exists or not).

I'm ashamed to say that since playing with test files the first few days of buying mine (around 10/1), I haven't played with mine much in the last week or so, simply because I've been busy with work, and also because I got sidetracked on another issue (trying to figure out how to deal with forced/necessary subtitles from a Blu-ray disc - a la Avatar).

I did play some Netflix stuff (my daughter played much more), and didn't really notice the issue, but also didn't look too closely for it. As you said, Netflix quality is pretty bad, so I don't expect too much out of it anyway. The big things I look for with Netflix are video tearing, because that's something that I got a lot of when trying to get Netflix playing back well on my Acer Revo nettop (Atom and NVIDIA ION GPU). I could never get it playing back on that without tearing, so I gave up on it. The other issue (which I see on my TiVo HD and Apple TV) is macroblocking (hopefully I'm using that term correctly) and/or artifacting with any degree of motion, but I chalk that up to Netflix's overcompression (low bitrate).

Back to the Apple TV stutter issue...As you said, there's a few different issues going on and I tried to steer people in that Apple TV support thread towards keeping it focused on the issue of the occasional minor stutter/judder type of issue, and not the type of issue where someone's bandwidth isn't fast enough and the movie pauses for several seconds. As you've noted, the occasional stutter/judder issue does not impact the audio at all.

As I mentioned in the other thread in these forums, I seemed to have fixed or at least greatly reduced the issue for me by turning off the advanced 3:2 pull-down settings on my 52" Sharp Aquos 120Hz LCD TV. Once the problem *seemed* to have gone away for me, I decided that if there was still an issue, other people would also be seeing it, and report it, and hopefully Apple could and would fix it. But if it seemed to be greatly improved for me, then I wanted to try to just "be happy" and stop looking for it, because it was driving me crazy.

So at that point I bought a 2nd unit (for my daughter's room) and got back into figuring out the best RF settings to use in Handbrake and, more recently, trying to figure out how to deal with Blu-ray subtitles. I do not own the older Apple TV, but instead am coming from having used a classic XBox running XBMC and playing a large collection of standard-def DVDs ripped as .ISO files. Then I got a couple of Acer Revos and started experimenting with Blu-rays and MakeMKV which, obviously, result in .mkv files. So I've got my work cut out for me to have to now convert all of those movies using Handbrake into .m4v files.

As a side note (in case anyone's wondering), I've made the decision (we'll see how that goes) of going with the Apple TV because of the end result simplicity of it all, even though that will require more up-front angst in terms of having to encode movies in a multi-step (and rather long) process of ripping/downconverting the movies. I can live with 720p and non-lossless audio since my current projector is only 720p anyway, and I like the idea of the filesizes being tiny and the ability to stream these movies wirelessly over the Apple TV's 802.11n without worrying about network hiccups causing stutters there.

 

[jajohns8]

I know, I am hoping the threads will be merged.

It sucks that a few (mostly trolls) are trying to dispute the fact that the problem exists, because it's a distraction from trying to find a solution.

Everyone wins if/when Apple fixes this.

All I care about is being able to watch my HD encodes without this crazy, subtle stutter.

 

[BlackMangoTree]

More discussion here http://forums.whirlpool.net.au/forum-replies.cfm?t=1544924&p=23

 

[badweasel]

As a side note (in case anyone's wondering), I've made the decision (we'll see how that goes) of going with the Apple TV because of the end result simplicity of it all, even though that will require more up-front angst in terms of having to encode movies in a multi-step (and rather long) process of ripping/downconverting the movies. I can live with 720p and non-lossless audio since my current projector is only 720p anyway, and I like the idea of the filesizes being tiny and the ability to stream these movies wirelessly over the Apple TV's 802.11n without worrying about network hiccups causing stutters there.

I agree with your whole post. Even though it's off topic I want to say why I prefer Apple TV over something like popcorn hour (which I have 2) or Xbox, etc.

On the downside AppleTV is only 720P and I would prefer to have a solution that can play 1080P. Popcorn Hour does and so do other streamers and some game systems. But the thing is, for 1080P to really be any better than 720P it needs to be at a much higher bit rate. When I was authoring BD's we never went below 18 or 19mps or you'd get a lot of macroblocking, dirty blacks, compression artifacts. And if I were the type to rip movies.. and of course I'm not - right? - because that would be illegal and wrong - but if I were, being the quality freak that I am, I would want the full quality of the BD disc. 1080 is about quality - and BD is already h264 - you can't make it smaller without losing the quality that you were going after in 1080. But that would mean that every movie would take up between 25 and 40 Gigs! That category of file size belongs on physical media. Well.. even if it's on a hard drive it's physical media - but you know what I mean: discs. Ultimately a choice has to be made between the full 1080P full quality version or something less that is more convenient.

AppleTV is super convenient! Along with iTunes it keeps track of what I have and have not watched. I can watch half a movie on one tv, stop, and go to another unit and it knows where I left off. Same with tv series.. I don't have to remember which episode I'm on. ATV/iTunes tells me. The quality of HD movies purchased and rented from Apple are much better than what I had previously seen on netflix. I have a 13 foot projection screen and 1080P looks AWESOME!.. but many movies look almost as good in 720P. Some movies you really can't tell the difference because they don't have the source quality to need 1080P. Even still, a few minutes into the movie your mind forgets to notice any differences between 720 and 1080. For certain movies I prefer to watch on the full 1080 BD experience. 7.1 is nice when it's available. But for most other things 720 5.1 is fine.

And of course SD material looks awesome on ATV. (Well, let's say it CAN look awesome on ATV).

Other players are just not as convenient. I need one file format that plays on iPad, iPhone, computer, and whatever streamer I'm using. And the streamer needs an easy interface so that my kids and parents can use it (popcorn hour is text based menus).

Back on topic. I trust that this issue will be resolved within a week or two. Then my two new ATV's will be joined with one for every TV in my house and my parents house.

 

[BlackMangoTree]

This issue doesn't really exist it's all in our heads. The forum i posted earlier i was banned from arguing that this problem is real. I was told i was a troll nt to make things up and was baned.

 

[hipnetic]

badweasel (and everyone else experiencing this problem), have you tried testing out your Apple TV on multiple TV's, and ensuring any advanced video processing (e.g., 3:2 pull-down) features are turned off? If not, please do and report back, even providing specific makes/models of the TVs/projectors you're using.

 

[benoitgphoto]

badweasel (and everyone else experiencing this problem), have you tried testing out your Apple TV on multiple TV's, and ensuring any advanced video processing (e.g., 3:2 pull-down) features are turned off? If not, please do and report back, even providing specific makes/models of the TVs/projectors you're using.

Well I don't know what settings you are talking about. I don't seem to have that on my Samsung plasma PN42C450.

Done some other tests yesterday and definitively the stuttering only happens when the movie is fully downloaded into the ATV buffer. Here are the conditions where I see it :

It happens on iTunes store HD rentals.
Doesn't happen on SD rentals.
It seems to happen on streaming from computer for HD content only too but need to repeat tests on that. Doesn't happen on SD content for sure.
Doesn't happen with Netflix HD streaming

Stuttering is very short and can easily be missed. I changed ATV1 for ATV 2 and this bug was not on the ATV1.

I don't think it is defect hardware as a defect one won't work at all I guess. And it's certainly not a network issue as the stuttering occurs only WHEN THE MOVIE IS FULLY DOWNLOADED TO the Atv buffer. Also, given those conditions, looks to me that software update will easily fix it.

I'm a big Apple fanboy. For example, I have an iP4 and I think the antenna is a non issue. BUT, this issue with Apple TV 2 is real and based on Apple support forum, it looks like Apple is aware of it and I'm sure this will be corrected in november with the release of iOS 4.2

 

[rz22g]

Temporary Stutter / Jitter Fix

I have tested this across 5 different 2010 Apple Units, using a different HD rental on each one, and found that it worked 100% of the time. This is just a temp fix but it will allow you to watch your movies without the jitter issue. I have not testing this on local content such as movies contained in your iTunes library.

1. Rent Movie and begin watching.
2. Keep track of buffer level by checking white progress meter (up or down arrow on remote)
3. White progress bar is the buffer. When it reaches the end (100%), this is when the jitters will start.
4. Reboot the ATV (Unplug power then plug back in)
5. Restart the movie. The buffer should still be full and it will playback without issue.

You may also be able to just rent and not start watching until the buffer fills. Not sure how that works. Point is let the movie buffer completely then reboot your ATV for smooth playback.

 

[IbisDoc]

LOL at the people saying it's a video settings issue. An old Apple TV, a PS3, an XBOX 360, a DVR, and a Blu-Ray player have no problems with video stuttering (on ANY setting), but this new POS needs a special video setting so that it works? This is almost as criminal as Apple's first generation MacBook Air failures.

"It just works." LOL.

 

[jajohns8]

Testing different setups

First off, I apologize for the length of this post. I think it's necessary to describe what I did in detail though.

So, I managed to bust out some old gear and try a few different setups in the hopes that I could isolate a component, other than the Apple TV 2.

Setup one is my standard setup of a custom built Windows XP machine, Linksys WRT320N Router, with CAT5E wire throughout my house.
(If you care, I used genesis systems/Honeywell Cat5E through out. Have had zero problems with it.)

The wrt320N was reset using the standard reset button on the back of the device to reset it to system defaults.
The only router configuration change was to apply a wireless password on the wireless network after the reset.

The machine that acts as my media server is a Windows XP box, with ASUS P5B Deluxe motherboard. The processor is a Core 2 Duo E6600 at 2.4.
I have overclocked in the past, but at present, this machine has been completely restaged and is 'stock.' (Win XP Pro with all current updates.) I have 2gb of Crucial Ballistix DDR2 PC2 5300 RAM.

I have a fresh install of the latest version of ITunes, whatever that is as of Sunday evening.

So the components are the: the wrt320N router, my Windows XP box, the Apple TV 2 and my TV, which is a Panasonic TCP42X1.

Again, I went with the wired ethernet approach because wireless is very flaky in my experience. I did however test it with Wireless N (on the wrt320n and G with the WRT54GL) just for giggles on both setups, and there was still the stuttering issue.

The test content:

I used a handbrake encode of my Ironman 2 Bluray. The handbrake version is a nightly build from the middle of last week.
The handbrake setting is the Apple TV preset, and then dimensions changed to 1280 x XXX.
The source fed to handbrake is the resulting .m2ts file from clownbd/tsmuxer's extract from my Bluray.
This is my standard practice for my blurays and have had no problems with it. (The apple TV 1 has no problem with it either.)

In addition to the above mentioned content, I have noticed the stutter with a similarly encoded version of the Lost in Space Bluray, and my son's first baseball game home movie footage taken with a Flip Mino HD camera.
The official Apple support thread (8 pages now and growing) has instances of Itunes Store HD material also stuttering/jittering/dropping frames.

Another encode of the Iron Man 2 source has also been made with Handbrake's High Profile preset, with the dimensions changed appropriately.
There is talk that this preset takes more advantage of the ATV 2 hardware.

The test:
So, I started playback with the standard Apple TV preset encode. The video looks great. We see Ivan Danko's house in Moscow, etc. Everything is beautiful.
During this playback I am hitting pause to see how the buffer looks. Buffer is not quite full yet.

Then, I notice that the subtle frame drop is occurring. It's very faint and very subtle, but noticeable. I hit pause again, and sure enough, the buffer is now completely full.

Then, just for giggles, I try the High Profile encode. Same results. Buffer gets full, frames start dropping. But man, oh man, until the buffer is full and the frames drop, it looks FANTASTIC.

So then, I switch out the Apple TV 2 for my trusty old Apple TV 1, 160 GB model.

No problems. Plays back the standard apple tv encode SMOOTH AS SILK. (Did not try the High profile on the Apple tv 1.)


I go back to the Apple tv 2. This time I decided to change the router.
I try my trusty old linksys wrt54GL, again with a system reset, only wireless security added.
Same results.
This router, the WRT54GL is the most generic, standard router out there. It is the 39X customer award winner from Newegg.

You can't find a more 'commonly used' router. It has a well earned, positive reputation.

I repeat the experiment, this time with my mid 2010 15" macbook pro, COre i7, 4 GB RAM. I love this machine. I have a fresh install of Windows 7 64 bit (using bootcamp.) I installed an Intel x25m SSD instead of the stock hard drive. It is my dream laptop for development work.

I downloaded the 64bit verson of Itunes and transferred my 2 test movies over to this machine.

I then performed this test with this machine as the workhorse.

Same results.

I try every combination of hardware in the mix. I try wired ethernet, I try wireless. Still have the problem.

What happens, is the buffer fills, and then something happens that causes the frames to drop on the Apple TV 2.

The Apple TV 2 drops the frames when the buffer is full, but the Apple TV 1 plays them back just fine.

EDIT:
Also want to add 2 ITunes store HD purchases are stuttering too. The shows purchased were The Tudors (one episode) and Grey's Anatomy. (also one episode.)

These were purchased first on my desktop and then streamed to the ATV 2.