Vegas 6 rendering performance

[dex Otaku]

I'm wondering what anyone else has to say re: Vegas 6's rendering performance.

By my experience here, it's absolutely dismal.

I can take DV25 clips and transcode them in Virtualdub with a deinterlacing filter active and have it render XviD at ~20fps.

The same clips, with no effects active, motion comp off, no rescaling, no processing done other than transcoding, moves along in Vegas at no greater than 4fps.

In fact, rendering anything from Vegas, even to uncompressed video, with no active effects, rescaling, deinterlacing or anything - moves at no more than 4fps. Adding rescaling and deinterlacing doesn't actually slow down the rendering speed, either.

This is rather frustrating, as I can preview the DV25 clips at 24-30fps in Vegas, but it can't render at more than 4fps. It takes seemingly forever to do anything of use.


Relevant system info: Athlon 2500+ Barton, 512MB RAM, WinXP SP2

[Zarxrax]

Try setting it to "good" quality instead of "best" quality, I think that will speed it up a little bit. But either way, you shouldn't use Vegas for simple transcoding or whatever. Just use virtualdub or avisynth whenever you can.

[dex Otaku]

Quality is already set to "good".

I usually use vdub et al for transcoding, what I'm using Vegas for is simple time-compression, which in this case is just using every 4th frame of video, so there's no real processing going on other than transcoding, as it's just skipping frames. One would think the overhead from that would be pretty low.

If you know of an open-source tool that does time compression [I'm converting video to timelapse, basically] I'd be happy to hear of it.

Cheers.

[Zarxrax]

Both virtualdub and avisynth can do that.

[dex Otaku]

I'm looking at avisynth. Users in another forum have already pointed me in the right direction as far as scripting is concerned. I expect that performance from avisynth will be at least an order of magnitude or two better.

Thanks..

[mic]

You are probably best going with V/Dub or Avisynth, as they are faster then any NLE I've tried on your sort of project. But, that's not an NLE's strength or purpose anyway, not where they put their energies in development.

Vegas is normally *maybe* a bit faster then something comparable like Prem Pro.. Version 6 IMO is very slightly slower then 4 going to mpg2, and then generally reports are aprox. realtime (ie. 2 hr for 2 hr video) with I think 2.8 P4 & up. Quality setting of best only applies to resize where it switches to bicubic -- shouldn't matter otherwise. DV performance is normally excellant -- one of Vegas' advertised strengths.

"I'm using Vegas for is simple time-compression, which in this case is just using every 4th frame of video, so there's no real processing going on other than transcoding, as it's just skipping frames. One would think the overhead from that would be pretty low."

I'm not at all sure Vegas is processing your video that way, just decimating frames rather then averageing & creating frames.

There's also a lot of info online to the effect that Vegas doesn't work that well, if at all with xvid. While most of that concerns import, it possible that the way Vegas handles color etc. could make for slow encode times, but that's just a guess.

Concerning the last 2 (decimation & rendering xvid), if anyone's having similar prob. & needs to use Vegas for editing, their support crew does monitor the user forums at the Sony site.

[adoniscik]

While most of that concerns import, it possible that the way Vegas handles color etc. could make for slow encode times, but that's just a guess.
I can tell you that Vegas uses RGB...