Why are video renders being so choppy?

Red Squirrel

No Lifer
May 24, 2003
70,540
13,791
126
www.anyf.ca
I just made a basic video with Vegas 9, nothing fancy, just took a video right off my still camera (low quality) and added basic text and stuff.

When I render it's super choppy, it like goes back and forth a few frames non stop, it's really messed. Makes it look like I had parkingsons while filming, but the original does not shake like this. I'm exporting with xvid codec at 25fps and res of 720x486. Anyone have an idea what would cause this or any other setting I could try? I have a CoreI7, 16GB of ram, SSD... it's not my machine. When I play the preview it does not do this.

Edit: Upon further experimenting, it only does it to the footage in the video I imported, anything I edited like moving text is fine, it's only the actual video from the mpeg file.
 
Last edited:

Modelworks

Lifer
Feb 22, 2007
16,240
7
76
The problem usually occurs with video imported, not only from cameras but other sources because encoded video, especially the mpeg2/4 kind were not created with editing in mind, so depending on where you make the edits parts of the information needed to re-create the frames may not be present. On playback the decoder tries to play the current frame, can't find the data it needs, so it keeps looking until it does, if that happens to be out of sync with where the decoder expects it to be you get a search, play, search, play appearance.

The easiest way to deal with any video that is already compressed is to convert it to a codec that was designed for editing. It does take a lot of hard drive space, but the video editing programs work much better after this is done. Compressed video is one of the reasons so many people complain about video editing programs crashing, often blaming the software for not being able to import their footage.

One codec that is quick and free as well is called lagarith. It was designed for editing video and is lossless in compression. I use it and virtual dub to convert compressed video , edit it, then encode it with whatever codec I choose , xvid, etc.
http://lags.leetcode.net/codec.html
 

Red Squirrel

No Lifer
May 24, 2003
70,540
13,791
126
www.anyf.ca
That's another thing I've noticed is video editing programs tend to crash a lot. So is that because of all the various formats of source video? Should I throw those in virtualdub or some other app to convert them to raw AVI first then import that file to work with it? What about that conversion process, wont the same issue occur? Or is it different because it's only converting a single video file and not dealing with extras added on top?