Multiclip editing is so slow.... at DVinfo.net

Greg Quinn · January 29th, 2007, 01:59 AM

I have four HDV clips (different angles of the same music event) that I'm editing as a multiclip, but the realtime editing playback is very jerky and almost impossible to edit (there's a huge time lag between me clicking on the angle and it changing). Is there some setting I'm missing to speed this process up? I'm using a Mac Pro 2.6GHz with 4GB RAM, and reading the clips off internal 7200 SATA drives. Surely multiclip eding shouldn't be as slow as this? The Mac Activity Monitor shows the CPU's being far from maxed out.

Thanks
Greg

Nate Weaver · January 29th, 2007, 02:55 AM

4 angles of HDV work pretty well on my dual 2.0 G5. So yes, something is up on your machine. Any effects on the clips comprising the multiclip?

Andy Mees · January 29th, 2007, 03:28 AM

i'd agree with Nate, 4 streams of HDV is not much considering the capabilities of your hardware... how many other apps do you have running? is the performance improved by a restart?

Greg Quinn · January 29th, 2007, 10:04 AM

Thanks for the replies and confirmation - I'm not at the machine now, but will try a complete reboot later. Would the multiclip display be affected by the type of codec used in the sequence (i.e. if it was using uncompressed)?

Patrick Pike · January 29th, 2007, 12:03 PM

I would make sure that there are no filters or motion changes made to your clips. Then, check to make sure the sequence setup matches your clips 100%. It sounds like the kind of behavior when your computer is attempting some RT changes while doing multicam.

Nate Weaver · January 29th, 2007, 12:20 PM

Quote:

Originally Posted by Greg Quinn

Thanks for the replies and confirmation - I'm not at the machine now, but will try a complete reboot later. Would the multiclip display be affected by the type of codec used in the sequence (i.e. if it was using uncompressed)?

Absolutely.

I'm confused, you said you were using HDV streams in your original post. HDV streams are about 3.5mbytes/sec. An uncompressed stream is about 100mbytes/sec...a HUGE difference. Unless you have at least a 4 drive SATA RAID, you're not going to be able to play back even a single uncompressed stream, much less 4. 4 would be insane.

You should do some reading on format data rates and how they effect editing.

Greg Quinn · January 29th, 2007, 02:17 PM

Quote:

Originally Posted by Nate Weaver

Absolutely.

I'm confused, you said you were using HDV streams in your original post. HDV streams are about 3.5mbytes/sec. An uncompressed stream is about 100mbytes/sec...a HUGE difference. Unless you have at least a 4 drive SATA RAID, you're not going to be able to play back even a single uncompressed stream, much less 4. 4 would be insane.

You should do some reading on format data rates and how they effect editing.

Thanks Nate, points well taken. I made a mistake, I ended up converting the HDV to AIC, which is uncompressed. I'm still fooling around trying to find a workable workflow on the Mac for 24P and the V1U.
Thanks again.

Nate Weaver · January 29th, 2007, 02:35 PM

Quote:

Originally Posted by Greg Quinn

Thanks Nate, points well taken. I made a mistake, I ended up converting the HDV to AIC, which is uncompressed.

Eh...Greg, AIC isn't uncompressed :-) Uncompressed is uncompressed.

It's usually about 13megs/sec. But that's enough to cause some problems on some machines.

Greg Quinn · January 29th, 2007, 04:39 PM

Quote:

Originally Posted by Nate Weaver

Eh...Greg, AIC isn't uncompressed :-) Uncompressed is uncompressed.

It's usually about 13megs/sec. But that's enough to cause some problems on some machines.

...hence the "codec" part of AIC - my bad. Without thinking, I assumed that because AIC file sizes were huge, it wasn't compressed, which of course was dumb.

January 29th, 2007, 01:59 AM	#1
Greg Quinn Major Player Join Date: Oct 2006 Location: San Diego, California Posts: 505	Multiclip editing is so slow.... I have four HDV clips (different angles of the same music event) that I'm editing as a multiclip, but the realtime editing playback is very jerky and almost impossible to edit (there's a huge time lag between me clicking on the angle and it changing). Is there some setting I'm missing to speed this process up? I'm using a Mac Pro 2.6GHz with 4GB RAM, and reading the clips off internal 7200 SATA drives. Surely multiclip eding shouldn't be as slow as this? The Mac Activity Monitor shows the CPU's being far from maxed out. Thanks Greg

January 29th, 2007, 02:55 AM	#2
Nate Weaver Wrangler Join Date: Oct 2002 Location: Los Angeles, CA Posts: 2,100	4 angles of HDV work pretty well on my dual 2.0 G5. So yes, something is up on your machine. Any effects on the clips comprising the multiclip? __________________ My Work: nateweaver.net

January 29th, 2007, 03:28 AM	#3
Andy Mees Major Player Join Date: Mar 2006 Location: Kuala Lumpur, Malaysia Posts: 645	i'd agree with Nate, 4 streams of HDV is not much considering the capabilities of your hardware... how many other apps do you have running? is the performance improved by a restart?

January 29th, 2007, 10:04 AM	#4
Greg Quinn Major Player Join Date: Oct 2006 Location: San Diego, California Posts: 505	Thanks for the replies and confirmation - I'm not at the machine now, but will try a complete reboot later. Would the multiclip display be affected by the type of codec used in the sequence (i.e. if it was using uncompressed)?

January 29th, 2007, 12:03 PM	#5
Patrick Pike Major Player Join Date: Sep 2004 Location: Mariposa, CA Posts: 200	I would make sure that there are no filters or motion changes made to your clips. Then, check to make sure the sequence setup matches your clips 100%. It sounds like the kind of behavior when your computer is attempting some RT changes while doing multicam.