Incremental Render Within Vegas

wwaag wrote on 5/26/2013, 9:29 PM
In this thread [Link=] requesting ideas for the debugmode frameserver, Johnmeyer wrote:

"1. Incremental render. Vegas provides "smart rendering" for a few formats, but even for those formats (like DV AVI), it never provided the ability to easily update an existing render. Suppose your computer just spent twenty hours rendering a thirty minute project, but you then find ten seconds on the timline that you need to change. The idea would be that you could simply create a region around the section that you have changed, and you would ask to render that, and that newly rendered section would be "spliced" into the existing rendered file. I do this all the time, using a variety of external tools, but it sure would be nice to have it done automatically. You'd need to get access to some AVCHD and MPEG-2 libraries that would let you combine together multiple files without re-rendering."

This can be done in Vegas for those formats that smart render. I do a lot of 720 60P projects in V12, and smart rendering for MPEG actually works (unlike V10). Here's what I do which is a real time saver. Once a render is completed, I add it as a new track. For any changes, I set up a loop region around the change and render (usually Cineform) it to a new video track using Rosebud's "Render to Video Track 1.5" script. The resulting "prerender" track is always on top. Once the corrections are made, I "solo" the top 2 tracks and render.

My current 25 minute project took a little over an hour to render. I discovered a missing fade, changed a couple of stills and re-rendered using the above technique in 9 min--a substantial time savings.

Perhaps someone else will find this useful, although I'm certain its not a new idea and claim no credit.


AKA the HappyOtter at System 1: Intel i7-8700k with HD 630 graphics plus an Nvidia 1050ti graphics card. System 2: Intel i7-3770k with HD 4000 graphics plus an AMD RX550 graphics card. System 3: Laptop. Dell Inspiron Plus 16. Intel i7-11800H, Intel Graphics. Current cameras include Panasonic FZ2500, GoPro Hero11 and Hero8 Black plus a myriad of smartPhone, pocket cameras, video cameras and film cameras going back to the original Nikon S.


HyperMedia wrote on 5/28/2013, 10:47 AM
Wow....this is what I have been looking for. I am currently working on several TV shows. The 44minute show sometime takes about 15 -20 hours to render. With 3D compositing and color correction effects.

What I was doing on a MAC is render out small sections before committing to the whole project. Very time induce workflow.

I'd research way back, smart rendering was only DV AVI.
Arthur.S wrote on 5/28/2013, 3:06 PM
I do that a little differently. As you I put the original render on a top track, but I just split it where I want to make my changes to show the project below. Make my changes, then render. This only recompresses the changes. If you want to keep the exact same file name, render to a different location from the original render - then copy/replace afterwards (Vegas won't overwrite something on the timeline). Thought that was the standard way of doing this?