A couple of questions

[Dave Haynie]

Does vegas have a particular problem with handling mpeg files? I don’t use this all the time myself but a friend and I were wondering. Whenever we use mpeg (and sometimes mov files) vegas seems to lock up and show “media offline” frequently.
The usual “media offline” message is displayed when you’re modifying the file in question in another application, or, of course, when the file is not actually there.

Vegas, like most NLEs, is not terribly tolerant of errors in media. Particularly if you’re seeing occasional red frames in MPEG video, that’s an indication you have some kind of corruption. Is this MPEG video from an HDV camcorder, or some other source? Are you editing in MPEG-2 TS (.mts, .ts, .m2t, etc) or MPEG PS (.mpg) format?

I haven’t had this problem myself with other formats so I wondered if it meant Vegas wasn’t really compatible with mpeg. Or could this be down to RAM, codecs or something like that? Just curious really.
I believe the MPEG-2 decoding is built-in to Vegas. In general, though, you can screw up your system by installing poor quality CODECs.. most video types, particularly Quicktime and AVI, are handled by CODEC plug-ins to a generalized multimedia subsystem. So the quality and reliability can vary greatly. One good reason to NEVER install a “CODEC Pack” like K-Lite… you may get buggy, slow, or otherwise inferior CODECs replacing your good ones.

MPEG is, however, more CPU intensive to work in that many other formats. MPEG-2 is slow, MPEG-4 slower still. The reason is that these are interframe compressed. So the first frame is independent, like a JPEG photo — the following 14 or so are based on changes made to that first frame. So Vegas needs more CPU processing and more memory to work in MPEG than something like DV or some AVI formats. And it’s of course worse if you’re editing in HD. Just the nature of the beast.

My second question concerns the preview window; no matter what I do (i.e. changing from auto to best full etc) it doesn’t seem to produce very smooth playback of transitions and effects. Is there any particular reason for this and anything I can do about it or is it just one of Vegas’ bugs?
Plug-ins are a similar issue. Each plug-in does some kind of video image processing. Each one you use adds to the CPU overhead Vegas will incur. Some will play back pretty nicely on a fast machine, others can’t. For example, I’m lucky to see 10fps peak out of the Neat Video de-noising plug-in, and it can be much less.

If you need to see and edit smoothly, and run our of CPU time to do this (and, given enough complexity, everyone will, eventually), you can selectively pre-render a section in Vegas. That’s the best option if you need to view the edited video. If you have lots of memory, you can also use the RAM preview feature, which sometimes makes things go faster.

And ultimately, video is one of the few things we do on computers that still needs more CPU time. If you’re editing HD video, you really want at least a decent quad core processor for this. My system is based on an AMD x6 (6 core) processor running at 3.2GHz, with 8GB of DRAM and 64-bit Windows 7. MPEG-2 playback on my system is “like butter”, MPEG-4 (AVC is the usual kind, also known as H.264 and MPEG-4 Part 10) is usable, but still slower than you’d like. If you’re seeing slow play without plug-ins in use on a four-core processor, you have some kind of problem.

If you’re working with an older processor, it’s your PC — you’re unlikely to see much different performance with any other editing program. Note that players can sometimes use resources unavailable for editing. For example, I can play back full HD in MPEG-4/AVC on my PC using only 6-7% of the CPUs cycles (that’s all six). This is because, using the right player, my nVidia 8800GT GPU is doing most of the heavy lifting. If I didn’t have that GPU, a CPU only play-back of AVC would take 40-50% of all six CPUs. So you can imagine, you might be in trouble even playing back full HD on a PC with only two cores and no GPU. Editing is more complex, and Vegas (and most other) NLEs don’t use the GPU to accelerate editing (they’re starting to… Adobe does this now).

-Dave

[Lisa Moate]

Thank you so much for your prompt and detailed reply. A lot of stuff makes more sense now. What you said about cpu explains a lot. I will have to give prerendering a go. That sounds like it might help.

Just to answer a couple of things. The mpeg format I was referring to was mpg and it was straight off the camera. Perhaps converting it to something else might have helped I don’t know. I use a different camera too that uses mts (avchd) and I haven’t the had the same problem with playback in vegas with that. It’s just with mpg that causes the most problems.

I can’t remember my computer’s specs off the top of my head but it has 4gb of ram and I remember saying at the time of purchase that I would be using it to edit videos (I know I was a little green back then and wasn’t quite sure what to go for). It has actually done me really well for what it is but one day in the future when I can afford it I would like to upgrade. I imagine that would make a huge difference from what you’re saying.

Thanks again for your help. Much appreciated!!

[Scott Francis]

If you are using a 32bit system, Vegas is not going to be able to use all 4 gigs of ram. It only sees 2 for its uses…this is a bummer and makes playback (in my experience) more ify. I have the same system and went to Win 7 64 bit from XP 32 and saw a world of difference all around….may want to think about that if you are still on a 32 bit system

Scott Francis
Mind’s Eye Audio/Video Productions

[Lisa Moate]

Thanks Scott that does make sense. I was planning on upgrading in the future but for the time being I am sorta stuck with what I have so I guess I’ll have to make the best of it, but at least I understand what’s going on now so thanks for all the help everyone!