How many m2t clips should be allowed in a project?

Laurence wrote on 6/21/2008, 8:22 AM
When Vegas first started being able to handle native m2t clips, there was a limit of around 85 m2t clips that could be on a single timeline before Vegas would crash. This of course led to all sorts of complaints and Sony listened and upped the number of m2t clips that could be handled to a higher number.

I don't know exactly how many m2t clips Vegas can now handle at once, but my experience is that it is a little less than two tapes worth of clips on average. This is assuming that you capture all the footage as individual clips and you are doing a run and gun type event with a lot of short clips.

When Vegas crashes, in my experience it usually just disappears without any sort of warning. One second it's there, the next it's gone.

I suppose that what is happening is that with long GOP clips, there is quite a bit of buffering that needs to happen since every frame is not a complete image without the frames that lead up to it. My guess is that there was a compromise made in estimating how many clips a typical Vegas user might need verses how much memory could afford to be dedicated to buffering m2t clips without affecting everything else.

Anyway, my question is this: How many m2t clips should Vegas be able to handle at once? Obviously the original number of about 85 wasn't enough, and to many of us, the new number of several hundred isn't enough either. On the other hand, I don't want to suck up all my memory to buffering more clips than I am going to use either. What do you guys think?

Comments

blink3times wrote on 6/21/2008, 8:40 AM
I've got 209 on the timeline rendering right now and I'm at 54% with no trouble...... yet. They're M2T files captured with Cineform and I'm rendering over to M2TS. I'll let you know in about another 1.5 hours.
blink3times wrote on 6/21/2008, 10:00 AM
It rendered through fine. Memeory usage was pretty steady at 2.8 gig or so (I'm running 8 gig ram with no page file).

To be honest Laurence I don't think it has much to do with the number of m2t files on the line. I think Vegas is simply being EXTREMELY picky at what it considers a valid m2t file.

My belief is that it has something to do with the way a capture utility (could be cineform or even HDVsplit) divides the clips for scene detections. In some cases you don't even have to do a render to get m2t crashes.... just scrub over a questionable m2t (or at least what Vegas sees as being questionable) on the timeline and the chances are great you will crash.

I had no trouble on this round.... but the next.... who knows. If it had something to do with quantity on the timeline then logically speaking there would be some kind of consistency to the crashing.
jaegersing wrote on 6/21/2008, 10:02 AM
If you capture with cineform, is it still m2t?
blink3times wrote on 6/21/2008, 11:42 AM
Cineform captures as m2t and gives you the option of converting to avi. It even gives you the option of doing both,

The other thing that SEEMS to work (so far) is capture with HDVsplit without scene detection or preview screen, and then use HDVsplit's option to scene split AFTER capture.
jaegersing wrote on 6/22/2008, 6:59 AM
"The other thing that SEEMS to work (so far) is capture with HDVsplit without scene detection or preview screen, and then use HDVsplit's option to scene split AFTER capture."

Haven't tried that before, will give it a go. Thanks for the tip.

Richard
FilmingPhotoGuy wrote on 6/23/2008, 2:01 AM
Blink 3times said "Memory usage was pretty steady at 2.8 gig or so (I'm running 8 gig ram with no page file).

I find this pretty interesting. You mean that you don't have a c:\pagefile.sys file? Is there a difference in performance if I render to 2nd drive while having 4 gigs of RAM and having a c:\pagefile.sys file of say 4 gigs and using your method?

I have a 4gig pagefile and 4gigs of RAM. I render the actual output file to a 3rd drive which seems to be the answer for me. I would imagine that Windows OS would also have memory needs which according to your method will share the 8gig RAM. I never thought of doing it like that.

Craig



riredale wrote on 6/23/2008, 7:59 AM
I can't speak for Blink, but my own conclusion is that for most stuff, memory needs are relatively small. For years I did many projects with just 1GB of ram, and the OS saw no need to swap chunks to/from a pagefile on a hard drive. I now run 2GB, bug only because DeShaker eats ram like candy during it HDV second pass.

You can see your actual memory needs by just opening up the Task Manager and viewing the Performance tab. Look at the Peak number under the Commit Charge box. This represents the most address space that your PC has needed since booting; if it's less than your physical ram total then it means there has been no need for a disk pagefile at all.

I could be wrong on some of this, but that's my current understanding. If you have lots of ram, you don't need a pagefile.
Laurence wrote on 6/27/2008, 6:36 AM
Getting back to the original thought of this thread, I have run into Vegas crashing problems recently because I have switched from tape to CF card on my Z7. My CF card is 32 GB which is approximately equal to two DV tapes.

My old process was to edit each tape down into a single highlights clip that I could use in a larger documentary style project. Vegas had no problem handling a single tape's worth of clips at once.

My new process is shoot to 32GB card (two tapes worth of clips), and Vegas will crash if you try to render from that many m2t clips on the timeline at once.

Thus I would say that for me at least, Vegas should be able to handle at least two tapes worth of short m2t clips at once before crashing. Right now it doesn't seem to be able to do this.
ShawnLaraSteele wrote on 6/29/2008, 10:15 AM
How many? As many as you want!

I'd think that this isn't a "limit", but rather a bug. I can get it to crash with far fewer clips than that! (10 or so). Even if there was a limit, it should say "buy more memory" or something rather than crashing.
riredale wrote on 6/29/2008, 11:21 AM
Just finished a documentary a few weeks ago.

Pulling up the finished project in Vegas 7d, here are some specs:

Size of project: running time 2:14, with 1:56 in main video and the rest in bonus clips.

5 video tracks on timeline.

4-channel surround sound (2 stereo tracks on timeline).

Video captured as m2t, DV proxies made with GearShift, edited as DV, then shifted back to m2t for final renders to MPEG2 for DVD.

GearShift says 291 clips are on the timeline.

Ram consumed by Vegas all by itself: 24MB.

Ram consumed by project with m2t clips on timeline: 460MB.

Ram consumed by project with DV proxy clips on timeline: 362MB.


With nearly 300 m2t clips on the timeline, Vegas runs rather lethargically, especially for those sections with color corrections and/or other effects. But it runs. This is on a AMDx2 system running overclocked at 2.5GHz and with 2GB of ram. When GearShifted to the DV proxies, no slowdowns at all.

There are about 75 other processes running on the background--this is my main system, and in addition to video editing it runs all my other stuff, including acting as a web server.
blink3times wrote on 6/29/2008, 12:13 PM
It may be just dumb luck so far, but out of three 1 hour videos now (averaging 150 scenes each), I have yet to have a crashing problem. I'm capturing with HDVsplit, and splitting scenes AFTER the capture.

Can some one else give this a try and see what they get?
blink3times wrote on 6/30/2008, 9:09 AM
The other thing I have come to notice when using HDVsplit is that the failure rate of the M2T files is much higher when using the "synchronize audio and video" switch.

I captured an entire hour with no scene split on the fly. I then did the scene split after the capture. I left the above switch on while splitting. The result was a bunch of crashing M2T files. I re-did the scene splitting with the switch off, and all the M2t files seem to work fine.

It may sound like I'm blaming HDVsplit here, but I am not.... Those same M2T files that crash Vegas work fine in other apps.