Need Help With Rendering Formats

RickD wrote on 3/24/2004, 5:41 PM

I have only been working with Vegas for one day so keep in mind that I don't fully understand this software yet.

The typical work that I do involves taking an AVI or WMV file that is already compressed for use on the Internet and editing it down to a smaller length. The problem is that I have not been able to find a way to render the edited files succesfully.

Let's say I load a 10MB AVI file into Vegas and trim away about half of the content. Now what I want to do is render it in essentially the same format. The assumption here is that I will end up with a 5MB file with the same video and audio quality.

What actually happens, no matter how I try to manipulate the render settings, is that I end up with a file that is greatly larger in size with very noticably degraded audio and video.

Can anyone explain to a new user how to go about saving a video file in essentially the same format that it existed in before it was loaded? For example, if you open a text file in Wordpad and then simply save it, the file is exactly the same as before being loaded and saved. How do I do the same thing with video files in Vegas?

Comments

JohnnyRoy wrote on 3/24/2004, 6:15 PM

You’ll need to know the exact format of the file you’re using in order to render it to the same format. So if you have a WMV file, you’ll need to know is it WMV V8, WMV V9?. What’s the bit rate? Is it 56 Kbps, 100 Kbps, 256 Kbps? Then when you render, select the same file type and select a template with the exact same bitrate. This should yield the same type of file.

Unlike your Wordpad example, Vegas will not sense the file type and render it out the same. Vegas works within its project settings and assumes you have set the project settings correctly for the type of media you want to manipulate. It defaults to DV AVI. (Although you can render to any type you want)

Note: You will probably loose some quality depending on the file format and if it has to re-encode the entire file or just the portions you changed. An AVI file only needs the changes re-encoded. MPEG2 requires the whole file to be re-encoded because of its predictive format. I don’t know about WMV.

~jr

busterkeaton wrote on 3/24/2004, 6:41 PM

What settings are you rendering to?

If you are working with a compressed avi and render it to the standard DV template, then the file size will be about 13 gig per hour of video.

RickD wrote on 3/25/2004, 5:27 AM

That's exactly what I am trying to do - render it in the same format as it existed. I have not yet been succesful. Everything I do results in some type of degradation and greatly increased file size.

I fully understand how Vegas uses its own format for editing, but what I don't understand is why it does not facilitate saving in the original format.

Let's use my text file example again but change the program to Microsoft Word. If you load a text file into Microsoft Word and edit it, you can then easily save it as a text file. You can also save it as a Word document (.doc) but then it becomes a proprietary binary format with additional information and increased file size. My question is "why doesn't Vegas facilitate saving an edited video in its native format?"

Once again, I understand that it can theoretically be done - if you know all of t he details of the source file - and set all of the render parameters exactly the same - but I have not been able to accomplish this yet. Even if I was able to accomplish it, it seems to be a serious deficiency to ignore users like myself who want to do simple edits to video files. In other words, why isn't there an option to "render in native format?"

stormstereo wrote on 3/25/2004, 10:19 AM

I understand what you mean but have never had the need for it. Suggest it to Sony under the support menu on this website. Maybe they'll hear you out.

Another thing - if you recompress already heavily compressed files such as WMV or QT the result might not be that good. If it's bad going in it will be worse going out.
Best/Tommy