Screensaver crashing when made with Quartz Composer using Asynchronous Mode?

att's picture

Hi all, I made a screensaver using video in Quartz Composer but the playback was choppy. I went into settings and used Asynchronous Mode, which sorted this out. It was running fine at first. Runs well in viewer and runs when I select test screensaver. I powered the mac up this morning and any of the screensavers using Asynchronous Mode no start for a second and then the screensaver stops suddenly. Again they work fine whilst test screensaver button is used and in the QC viewer but suddenly not when I use hot corners or when the Screensaver activates???

Any help would be much appreciated. Thank you

Using Snow Leopard 10.6.8

cybero's picture
Re: Screensaver crashing when made with Quartz Composer ...

Does your movie use sound?

If not you shouldn't need Asynchronous mode.

That said you stated Asynchronous mode improved the qtz's constructs movie playback in QC.

Clearly doesn't extend outside of QC when drawing upon the QC framework as a Screen Saver.

Asynchronous mode playback ignores the QC timebase. That's the stumbling block.

I made two virtually identical screensaver examples.

One uses Asynchronous mode [B]. The other doesn't [A].

The Asynchronous mode screensaver won't playback at all, other than in Preview mode in the System Preferences Screensaver dialogue box - otherwise it doesn't even attempt a start up.

The default Movie Patch mode version works every time.

This is exactly what should happen.

The slight difference I have to report in the failure of an Asynchronous mode movie and default Movie Importer patch on my system and yours will no doubt be down to the differences between Snow and Mountain Lion.

If you are looking to improve the playback of your movies in the screensaver, ensure that they are not way too large in MBs and that the video frames aren't kind of jumbled. Open in QuickTime Player [movie file not qtz] try scrubbing the playhead - does it stick or does it scrub? If it sticks, I'd re-render again.

Asynchronous mode works well in QC all told though for all that is said above. It's just the Screen Saver mode deployment where Asynchronous won't play [got no reliable QC timebase you see].

PreviewAttachmentSize
examplemoviescreensaveA.qtz1.04 MB
examplemoviescreensaverB.qtz1.04 MB