Vegas Video discussions from 2003

[Joe Sacher]

If I do what Ed does, the intermediate renders are DV format. If I must have absolute best quality, you can frame serve each of the many Vegas projects into a final project that combines them. There may be some limitation of the number you can do that with. I've only done it with 4 or less.

[Edward Troxel]

I render to NTSC-DV AVI files. Since nothing will need to be rerendered in the final project (unless you create dissolves between the clips), you will get NO loss of quantity as no additional rendering will be required.


If you purchased and are currently using Tsunami, you have the manual - it installs in the same folder as the program. You should also be able to find it by going to start - programs - tsunami.

[Tom Voigt]

But afterwards I did whatever I had done and did it again.

If you can pull the windows start bar down you can grab the errant window.

[Tom Voigt]

One point I don't have a firm answer on:

When re-encoding an existing MPEG with the same settings (bitrates, etc), do you take a quality hit?

My eyes say no. Not to say there isn't one, but I don't see it.

[Tom Voigt]

I have been doing all of my concert pieces in 16:9.

Before I got DVDA, I rendered to a 4:3 avi or mpeg with letterboxing for final output (which was SLOW).

Now with DVD Architect I render out to a widescreen MPEG and make a DVD.

Then I play the DVD and copy to VHS. Voila! Instant letterboxing!

-Tom-

[Edward Troxel]

SO QUIT DOING IT!!!

Seriously, the method for "tearing" the windows from the bottom area is to click on the thin line to the left of the window. When you click there and drag, you will get a free floating window. If you hold down the control key while dragging a window, it will prevent it from snapping into the bottom area.

As for what you are doing to get them all below the start bar, I'm not sure.

[Edward Troxel]

Yes - you WILL take a quality hit. Any time MPEG is rendered, it must be uncompressed and then recompressed. Now, depending on bitrates used you *may* not be able to visually see it but there IS a hit.

BTW, why would you need to reencode an MPG at the SAME bitrate?

[Bruce A. Christenson]

Is the MPEG-2 encoding such that you will get different results each time?

For example. What if I create an MPEG-2 from my miniDV source, then I start encoding that MPEG-2 with the same settings over and over and over again? Would the quality degrade with each iteration (like copying audio cassettes), or ... would the result of each encoding be exactly the same as the next (and prior) encoding, because all the 'information' the compression scheme throws out in the original encoding is already gone, leaving the compression algorithm with no real 'work' to do?

Just curious.

PS - I would also like to see the ability for the end of one selection in DVDA automatically start another selection, without having to use chapter points from a single selection.

[Edward Troxel]

If you start with an AVI and render to MPG from that AVI multiple times, you should get the same results. Where you are going to get a quality hit is if you take the MPG file and render to another MPG file. Either go back to the original AVI each time or don't re-render!

I'm still wondering why you would NEED to re-render - especially from MPG to MPG.

And, yes, end actions would be nice.

[Bruce A. Christenson]

I hear about a lot of people who receive (original) DVD-Rs that the customer wants re-edited, new titles, etc. So people are always asking if re-rendering files they rip off DVDs will suffer in terms of quality. They can never seem to get their hands on the original source material. Examples include poorly edited or mis-spelled titles in wedding videos done by someone's brother-in-law's cousin.

I get suspicious just blindly accepting 'generation loss' in terms of MPEG encoding, because (in theory) if the first encoding has removed all the 'information' that the compression algorithm needs to throw away to reduce file size, what else is there for multiple encodings to throw away? (Assuming the encoding settings are identical.)

[Edward Troxel]

I get suspicious just blindly accepting 'generation loss' in terms of MPEG encoding, because (in theory) if the first encoding has removed all the 'information' that the compression algorithm needs to throw away to reduce file size, what else is there for multiple encodings to throw away?

Because the second encode will throw away DIFFERENT pieces of information based on what IT sees.

To re-encode from MPG to MPG, you take a compressed video, uncompress it, and then recompress it. This WILL result in a loss of quality. Whether or not it is visually noticable will depend on the original and new bitrates but, even then, there WILL be a loss.

There are many programs available that will convert a DVD to AVI. However, many people actually prefer to capture to AVI while playing the DVD through a convertor/deck/camera.

Bottom line: you WILL lose quality but it may be small enough to not be noticable.

[Steven Galvano]

Having a rough time in playing back Vegas.

I have a new 2.8ghz/800 1gig ram, etc computer,
but I am getting jerkiness/slight freezes in the viewer.
Happens playing both from the timeline or previewing from and media pool. The jerkiness does NOT increase (stays about the same) no matter if I am previewing in full res, or in draft mode.
Running under XP home.

Steve

[David Newman]

This is the problem with running M2T natively through Vegas. Our Connect HD product that will ship in January is targeted to fix this very problem. Watch www.cineform.com for product release information.

[Paul St. Denis]

I have not tried this but it might help, how about dragging your "m2t"s into Vegas and then right after, render them as either a Huffyuv or uncompressed AVI. Use that file to edit with rather than the "m2t"s.
The jerkiness is probably coming from the interpreted frames in MPEG video, Vegas needs to gather information from neighboring frames in "P" and "B" frames in order to display them properly.
Mac people are already doing something similar by using Pixlet or DC30 converted from m2t's to edit rather than MPEG.
Warning the AVI files are going to be much larger than the original mt2 files.

[Alex Raskin]

Actually, trying to edit uncompressed or HUFFYUV files will most likely choke the editor as these files require super-fast data transfer and processing.

Here's what I do: two-step approach to editing.

Step 1: Convert all m2t files into small-footprint AVIs and do the edit in your fave software (Premiere Pro in my case.) I convert to PicVideo codec ($99 download) that is only 27Mb per minute at quality level 16 out of available 20. Very nice image quality (subjectively, looks better than any other small-footpring codec I tried), acceptable for confident editing. Make frame size 640x360, so it's even smaller than DV (no choking of the editor - get Real-Time previews all the time) and proportions are the same as in the original 1280x720 file.

Step 2: Once edit is complete, simply replace these source AVI files with the final-render AVIs (make sure file names are the same.) This time I use HUFFYUV codec for m2t conversion, at the original 1280x720 frame size (2Gb/minute). Once source AVIs are replaced with HUFFYUVs, re-open your editor and render the project. Works like a charm in PPRo. (This time you don't need real-time previews, as the edit is already complete; what you need is high quality render, which you will get with lossless HUFFYUVs.)

Conversions can be done in batches, which is quite speedy and convenient - just write your little software program to automate the process (I did) or find some batch software on the web.

Or do it manually :)