Tiger's QuickTime Misperforming on an iBook G3?

November 2, 2005 8:35 AM

Ever since upgrading to QuickTime 7 and Mac OS 10.4 (Tiger), I've noticed that apparently what I think is the H.264 and H.267 codecs play very choppily on my machine.

The audio track doesn't freeze, but the video stops, then moves forward slightly choppily, then goes forward, then repeats the cycle a few seconds later, making the resulting video mostly unviewable. I've noticed this specifically on videos from the iTunes Media Store and Apple Movie Trailers.

My machine isn't horribly ancient, but it's not top-of-the-line, either: an 800 mHz iBook G3 with 640 MB RAM (which is the maximum available for this unit). I know the G3 is at the hind end of the pack nowadays, but I can't believe it's been entirely ignored when these codecs were tried out at Apple.

I have tried three things: increasing the QuickTime cache (no effect), reducing the number of open applications at the time (very little or no effect), and letting the whole video load before trying to play it (very little or no effect).

Any help would be appreciated. Thanks.

posted by WCityMike to computers & internet (11 comments total)

I've noticed the same thing on a 1.33gHz machine with 768MB of RAM, except the skipping is a tiny amount when I'm doing a lot of things.

I think the processor just gets more of a workout when decoding H.26X stuff. It doesn't really have anything to do with Apple "ignoring" your computer.
posted by odinsdream at 8:40 AM on November 2, 2005

I have a g5 with 1.5 gigs of ram and every single quicktime movie for me stops halfway through for about 8 seconds before continuing on. It's a pain in the ass.
posted by Manhasset at 8:44 AM on November 2, 2005

H.264 takes an awful lot of CPU. An 800MHz G3 without AltiVec probably just isn't enough to play it. Check out Apple's specs -- you need some pretty fast hardware to play the higher resolutions.

Your only other option would be to give VLC a shot.
posted by zsazsa at 8:58 AM on November 2, 2005

Turning on Quartz 2D Extreme (which is not the same thing as Quartz Extreme) has been known to help .264 playback.

Having said that, I think your horribly ancient machine is just too weak to be able to use this codec in real time.
posted by majick at 9:48 AM on November 2, 2005

How's hard drive space? Volume fragmentation isn't a problem with Mac OS X, but it's important that you don't have too much file fragmentation. If you're viewing large video files and have little free hard drive space, it's possible that it's jumping around the disk. Available memory is an issue, but you should be fine on that front.
posted by mikeh at 9:51 AM on November 2, 2005

I have the same machine as yours, and the same thing happens to me occasionally - I just quit all other open applications (OS 9 nostalgia!) then do a quick ps -aux -c in the Terminal to see if there's stuff in the background still hogging CPU and kill whatever is. Oh, and sometimes just disabling the Dashboard will do the trick: killall Dock will get rid of it until you next invoke it, or you could get something like the DashOnOff preference pane.

I find VLC fares a bit better with most video, but sometimes have to quit other apps with that as well.
posted by jack_mo at 10:23 AM on November 2, 2005

Turning on Quartz 2D Extreme (which is not the same thing as Quartz Extreme) has been known to help .264 playback.

Unfortunately you can't do that anymore (10.4.3 removes the capability).
posted by kindall at 10:26 AM on November 2, 2005

The video card in that iBook wouldn't support Quartz 2D Extreme, either.
posted by zsazsa at 10:35 AM on November 2, 2005

Well, I can't say the answers were what I were hoping for, but thanks, everyone. (Can't say I'm too pleased with Apple, either. Not everyone can afford to replace their computers every few years -- at least not with Apple's prices.)
posted by WCityMike at 6:19 PM on November 2, 2005

Yeah, I have the same model iBook, but the 600Mhz version. Most QuickTime videos play okay, but I've started noticing some that play more like a slideshow or a badly-managed PowerPoint presentation.
posted by blueberry at 4:31 AM on November 4, 2005

The latest QuickTime or OS update seems to have alleviated the problem somewhat, although not altogether.
posted by WCityMike at 7:41 PM on January 28, 2006