0.9.2 Serious AppleTV Playback Stuttering

[VKX]

I'm getting a lot of stuttering from my new DVD rips on AppleTV. I'm using:

4000kbps
720x400
Non-Anamorphic
No Deinterlace
Current Framerate
AC3+AAC

Even when the videos are synced to AppleTV, it seems like high action scenes are really suffering upon playback. They stutter and jerk a bit, although it's not a buffering issue. No matter how many times I synch, rewind or play back, I get the exact same stutters at the exact same areas. When I play the same files on my Mac Mini, there's no stuttering at all.

What gives? Any ideas how to fix it?

[nightstrm]

I'm getting a lot of stuttering from my new DVD rips on AppleTV. I'm using:

4000kbps
720x400
Non-Anamorphic
No Deinterlace
Current Framerate
AC3+AAC

Even when the videos are synced to AppleTV, it seems like high action scenes are really suffering upon playback. They stutter and jerk a bit, although it's not a buffering issue. No matter how many times I synch, rewind or play back, I get the exact same stutters at the exact same areas. When I play the same files on my Mac Mini, there's no stuttering at all.

What gives? Any ideas how to fix it?

Without knowing exactly what options you are using (since you are obviously not using a preset), then there is no way anyone here can tell you with any certainty what your problem is. If I had to guess, I'd say you're seeing bitrate spikes that exceed the capabilities of the AppleTV, causing the stuttering. This has been discussed almost to death on this forum; you can't just change the settings to whatever you want and always expect things to play nicely.

[VKX]

So how do I eliminate those bitrate spikes?

[VKX]

Also, I clicked the AppleTV preset, and then got rid of anamorphic and changed the bitrate from 2500 to 4000.

[rhester]

got rid of anamorphic

Why?

and changed the bitrate from 2500 to 4000.

What are your vbv-maxrate and vbv-bufsize settings in the Advanced Options tab? (Hint: If you don't have any, which are present in the preset for a reason, you will experience stuttering due to bitrate spikes.

Rodney

[VKX]

Thanks in advance for your help. I don't think there's any vbv-maxrate or vbv-bufsize specifications in my advanced options tab. What should I set them to to prevent stuttering.

[rhester]

The ones in the preset as-shipped were designed to avoid exactly this problem.

Rodney

[jbrjake]

The AppleTV preset has *never* used VBV.

[VKX]

Ok, I get that, but I don't want 2500kbps. I want a much higher bitrate for my encodes. On 0.9.1, I could get away with 5000. I decided with 0.9.2 to move down to 4000kbps because of the additional space needed for 5.1. How can I make an encode work without stutters on AppleTV at about 4000k?

[rhester]

jbrjake,

Really? The many months of effort dynaflash put in was never actually shipped?

dynaflash,

Can you make a recommendation on VBV here? To my knowledge, Apple never posted hard data on the buffer size, so I believe your trial-and-error figures are about all we've got that's sane.

Rodney

[dynaflash]

4500/3000 is working nice with 68% even with cabac on , However, imho an abr of 4000 is very excessive. At crf 70% very few encodes end up in the 4000 range and generally speaking, 70% is considered close to transparent.

However, if the OP insists on 4000, I would definitely use

Code: Select all

:vbv-maxrate=4500:vbv-bufsize=3000

We never added it to the stock preset as it does not use cabac and with an abr of 2500 its not really needed for the most part.

[dougzer0]

4500/3000 is working nice with 68% even with cabac on , However, imho an abr of 4000 is very excessive. At crf 70% very few encodes end up in the 4000 range and generally speaking, 70% is considered close to transparent.

However, if the OP insists on 4000, I would definitely use

Code: Select all

:vbv-maxrate=4500:vbv-bufsize=3000

We never added it to the stock preset as it does not use cabac and with an abr of 2500 its not really needed for the most part.

I'm hesitant to pick up an AppleTV based on the contents of this thread http://discussions.apple.com/thread.jsp ... 9&#6825449. However, based on your post dynaflash I assume you are streaming to AppleTV 2.0 with little/no stuttering?

I have a D-link wired Gamerlounge gigabit router and a MediaSmart with 2G memory and will be installing iTunes directly on the MediaSmart. The AppleTV will be wired to the router as well (though in a separate room on the other side of the house). So I'm not anticipating network bandwidth issues.

I also have a PS3 but really want support for chapters (and AC3) which is driving me to the AppleTV. I do have AAC 6 channel working on the PS3 which mitigates the lack of AC3. I was hoping that Sony would announce movie/netflix download soon that might include support for AC3 / chaptering, but now i've run out of patience. I haven't seen any discussions regarding the bitrate limits on the PS3 tho, and have never experienced stuttering using the PS3 presets. However, several people have experienced stuttering on the PS3 with the latest 2.20 update, which I have yet to install.

[dynaflash]

4500/3000 is working nice with 68% even with cabac on , However, imho an abr of 4000 is very excessive. At crf 70% very few encodes end up in the 4000 range and generally speaking, 70% is considered close to transparent.

However, if the OP insists on 4000, I would definitely use

Code: Select all

:vbv-maxrate=4500:vbv-bufsize=3000

We never added it to the stock preset as it does not use cabac and with an abr of 2500 its not really needed for the most part.

I'm hesitant to pick up an AppleTV based on the contents of this thread http://discussions.apple.com/thread.jsp ... 9&#6825449. However, based on your post dynaflash I assume you are streaming to AppleTV 2.0 with little/no stuttering?

Do not be afraid of the AppleTV. Like *all* things there are limits to what it can handle. Imho the OP is using very excessive bitrates which leave little to no headroom for local bitrate spikes without some vbv buffering limits in place (which I have outlined above and which are largely unnecessary with the stock appleTV preset). Having said that I personally test streaming but prefer to sync. The problem with streaming is that you start introducing network variables into the equation which are largely beyond the AppleTV's control. I do not want to get into semantics of particular network setups, but suffice it to say that with the OP's abr and the vbv I outline above, you should see decent streaming on an N wireless network. Provided you use the 5 GHZ range only. But to me it is a moot point because for most sources the abr is beyond transparent for the most part. So its a waste.

Use the stock HB AppleTV preset and you should be pretty much happy with most AppleTV playback configurations. If you decide to "go for broke" afaik the most comprehensive empiricle testing of the ATV's limits is this thread: http://forum.handbrake.fr/viewtopic.php?f=7&t=5129 where at the end you will see settings that are more or less agreed to provide consistent smooth playback at a very nice video quality. The whole thread is worth a read if you are serious about using your AppleTV "on the edge" so to speak. If you just want a guaranteed click and encode solution you are safe with the stock HB AppleTV preset.

Hope that sheds some light on things a bit. For the record, since I got my atv right after they first came out, I removed my dvd player from my system and frankly really do not remember where I put it

[dougzer0]

ok thanks !


i see ... maybe will try at some point with 68%

bframes=6:ref=6:mixed-refs=1:subq=6:me=umh:no-fast-pskip=1:trellis=1:weightb=1:bime=1:brdo=1:direct=auto:vbv-maxrate=4900:vbv-bufsize=3500