[jeronimo]

Hello everybody...
Does the iMovie 2 take advantage of the Altivec stuff on a G4?
Thanx

While I don't know of the specifics of how it was coded, there are certain operations that any program running on a G4 perform that use the AltiVec units. Because the OS was written to take advantage of them, certain operations (like copying large blocks of data from one part of memory to another) will automatically use the AltiVec units, and hence be sped up. So you should see some speed ups, even if the code for iMovie was not specifically AltiVec enabled.

-D

still doesn't quite answer the question though: is iMovie 2 specifically coded to take advantage of AltiVec (Velecity Engine or whatever Apple wants to call it) operations to speed up rendering (for example)?

P.S. Slightly off the subject, but is iMovie 2 carbonized? Anyone tried running it under X?

[Vision]

I don't beleive iMovie specifically takes advantage of AltiVec. Perhaps in compiling, the Apple optimized it for G4/Altivec, but since it's always been geared for iMac users, I suspect they didn't.

And iMovie is NOT Carbonized. You can always check to see if a program is carbonized by opening the program in ResEdit. If it has a "carb" resource, then it is (or should be) carbonized. A couple of programmers screwed up and left the "carb" resource in a Classic application, but if there's no "carb" resource, then it is definitely not a Carbon application.

No it does not take any atvantage yet.
Zero

I tried iMovie 2.0 under OS X and can confirm that it is NOT carbonized. It's a great program and I am looking forward to a carbonized / Altivec / MP aware version to come out. Often, I'll do 5 or 6 transitions at a time once I have my clips in place. Hopefully iMovie 3.0 will address these issues.

[Thunderbird]

I think I read somewhere that all applications that use Quicktime are both MP aware and Altivec optimized for the specific operations that use Quicktime. Is that correct?

[michaelb]

I think I read somewhere that all applications that use Quicktime are both MP aware and Altivec optimized for the specific operations that use Quicktime. Is that correct?

Yes, that is correct.

The recently released QuickTime 5 Public Beta ("Preview", "Work In Progress", whatever) contains a much faster DV algorithm that will speed up any app USING QUICKTIME for its DV functions.

QuickTime 5 is also MP aware: some apps get it for free (eg an app using QT for image compression will probably get a boost), while others must have minor changes made to their API calls in order for MP benefits to come through.

According to the preliminary QuickTime 5 developer documentation, MultiProcessor G4s can speed operations by almost a factor of 2. Two brains are indeed better than one, and we don't have to wait for Mac OS X for that to be so.

Get QuickTime 5 at:
http://www.apple.com/quicktime/preview

[Randycat2001]

Can anybody substantiate (with some simple benchmarking) whether or not Quicktime operations really benefit from any acceleration from Altivec or MP? I'm really interested to see more info on this topic. Does Quicktime 4 have any of this functionality or is it only 5? Specifically, I would like to know if exporting to various video formats (in Quicktime and/or iMovie) and ripping to DV are sped up at all. Its only up to now that I have found something that actually ties up my BW G3 350 for long periods (she is ravenous in virtually anything else I routinely do on it), so I need to know if a G4/MP upgrade would make any difference at all.

[Euphrates]

They have iMovie 2 for OS X, I don't know what everyone is talking about. It is just a different version.

Go to iMovie for OS X and download the program. Simple as that...

[Randycat2001]

Well I did a quick test on a G4 demo model at CompUSA (probably a 466 or 533 and most likely Quicktime v.4.x) encoding that sample movie that comes with iMovie2 to Sorenson format. It was about 40 sec of video, and it timed out around 15 minutes to encode. That's not much better than my G3 350 that does 1 minute of video in around 20 minutes to Sorenson format! So I'm not too impressed with the prospects of a G4 upgrade (after all, Quicktime video compression seems like an obvious for Altivec functionality, but that does not appear to be implemented in my informal little test). I even watched the progress pointer during the encoding, and it didn't seem to move any faster than like it was on my machine (certainly not Altivec kind of speed). Oh well...

BTW, anybody know what the technical differences between H263 encoding and standard Sorenson? Why does H263 encode so rapidly (albeit with less video quality, of course)? Cinepak, 3ivx, and Sorenson all seem to encode about the same speed, but H263 really moves in comparison.