iMovie - Multithreaded or not?

They rely on QuickTime, and I don't think that QuickTime is.

I'll check on my multicore G5 and Intel Mac mini tomorrow..

Hi

For what it's worth.

Experimented with FinalCut Studio 2 FCP6 Yesterday and applied "Smooth Camera"
filter.

Activity Monitor showed about 166% work load by Smooth Camera filter.

May be different filter are more or less multi treaded.

I used a dual G5 2GHz Power Mac.

Yours Bengt W

afaik, all iLife apps are not multi-cored...

.. looking forward to 10.6./Jan 09 ..

With Final Cut, some operations may use one core. Some may have multiple threads that can be spread over a couple of cores. But the real productivity boost comes because you can so separate operations across multiple cores. For example, you can be editing a project while compressing or rendering at the same time for a different project.

I don't think they're multi-threaded, or whatever the term is.

As Appleman says - below - the advantages of multiple cores with iMovie are that different jobs can be doing their own things simultaneously without interfering with others ..like QuickTime transcoding a video file using one core, and material being saved to disc using another, while a third operation (e.g; manipulating what you see onscreen) can be handled by another.

When Exporting as a QuickTime movie from iMovie '08 on my quad G5 my Activity Monitor (..Applications>Utilities>Activity Monitor..) shows this kind of thing..



..which appears to show that the process is being "handed over" between different processors so that they all get a bite at the cherry, but it's not being split simultaneously between all four.

My " iStat pro" Widget shows a similar distribution of the load, with different processors handing it back and forth rather than all working together on the one job:



My Intel Mac mini has only two cores, and there's insufficient difference between them - using Activity Monitor - for it to be worth posting any pictures.

So iMovie's a bit of a single-core "plodder", but I think QuickTime's always been that way. Now, when Snow Leopard arrives, with its 'Grand Central' farming-out of processes through the graphics processor ..oh; wait; I don't think that'll do anything for PowerPC Macs like mine, and my Mac mini has no dedicated graphics memory, so, er ..never mind!

iMovie does what it does in the way that it's been engineered to work, and I'm OK with that. Final Cut Pro HD uses multi cores, I believe, for handling much of the rendering (..video adjustment..) which it, or 'Motion', does ..but any operation requiring conversion of video via QuickTime still uses just one processor at a time, as I understand.

But then again ..who cares..?