Small problem after compression

B3RZERK · Post by **B3RZERK** » Tue Jun 05, 2007 5:09 pm

Hey everyone. I have a small problem:

I compressed a .AVI file using VirtualDubMod with Lagarith codec. It came out as 25.5 GB. Now the problem is that everytime I play it, it lags alot, for about 10 seconds, then it's normal for like 3 seconds then lags again etc. Does anyone know what's the cause of this? Is it because the file is too large, or something else? My computer has 1022MB RAM by the way, if that has anything to do with the problem.

Org Profile · Post by **808-buma** » Tue Jun 05, 2007 5:18 pm

it has more to do with your processor speed. LAGS files are not meant as playback files (well, unless you have a fast computer). LAGS is a highly compressed lossless format so it puts a lot of demand on your cpu for processing images, so if it can't keep up, it will do what you mention in your posting.

If you want to actually watch the file, you'll have to encode it with a distribution codec (such as xvid, etc) rather than an editing codec (like LAGS, or Huffyuv).

hope that helps

B3RZERK · Post by **B3RZERK** » Tue Jun 05, 2007 5:22 pm

Thanks, one more thing though:

I wanted to use it for editing, but since it lags during playback, wouldn't it also lag when I import it into an editing program (I'm using Sony Vegas 7.0 by the way)?

Org Profile · Post by **808-buma** » Tue Jun 05, 2007 5:29 pm

well, again it depends on how fast your cpu is. If you have a slower processor, you can use the 'bait and switch' method (use a faster, lossy codec such as mjpeg to edit with, and once you've finished that, switch it with the lossless encode for your final output). There's a tutorial on the site, somewhere... but since I started making vids, my computer has just been fast enough to edit with the lossless codecs so I've never actually done the bait and switch method...

hope this helps

Scintilla · Post by **Scintilla** » Tue Jun 05, 2007 5:46 pm

I can confirm that HuffYUV, at least, certainly lags/skips less in my NLE than AVISynth scripts do; however, this still doesn't mean I'm going to stop editing primarily with scripts anytime soon.

JaddziaDax · Post by **JaddziaDax** » Tue Jun 05, 2007 6:22 pm

i get a bit of lag with lagarith files in Vegas 6.0 (which im sure is pretty much the same as 7.0 when it comes to that...)

either way my suggestion if you want smooth playback... create a loop region and hold down "shift" and hit "B" it will do a prerender and you can play that one piece as many times as you want without lag... (atleast till you change it in which case you will have to "shift b" again)

if you want to be able to preview more of your video, go to Options then Preferences then Video and make the Dynamic RAM Preview max (MB) number higher.