> ...one could cross-reference the timecode with Vegas and trim in the Vegas timeline so that the clip starts exactly on an I-frame before archiving. Then in theory there would be less quality loss (if any) than if the clip were trimmed between I-frames and all the I-frames were re-jigged for the whole clip. Right?

Wrong. You are not getting it. As Laurence said, Vegas will re-render the entire thing and loose quality no matter what you do. Why don't you listen to us? Just go buy Womble and cut out the stuff you don't want and it will copy the rest at fully fidelity. It's as simple as that.

~jr

I am listening Johnny, very closely. Just thinking around the subject, that's all.

From your first reply I inferred that possibly the re-timing of the i-frames might be the prime reason for the quality loss in re-rendering m2t, so I'm just suggesting a method of re-rendering using the same i-frames. Now I know, thanks to you and Laurence, that this won't really help, so I'll go back to other methods such as Womble.

Thanks very much for your help. I appreciate it.

If you decide to use Womble, make sure to look at MPEG VCR and not just MPEG Wizard. MPEG Wizard lets you do editing of separate clips, titles, narration etc. but MPEG VCR is simpler for trimming. It also lets you add trim points to a batch file so that you can set all your inputs and outputs quickly, then take a break while it recopies the trimmed files. Another thing it will do is let you separate the audio from the video into two separate files. Cool stuff when you get into it!

Thanks again Laurence.

I've been testing both Womble products. The keyboard shortcut to move to the next I-frame ( CTRL + > or CTRL + < ) only seems to work in the more expensive MPEG Video Wizard.

I'm wondering about using Vegas scripting to output a custom edit decision list from Vegas that can be used as a media list (.wbl) in Womble. That way I won't have to do all the trimming again, I could just use the trim points that I had decided in Vegas (and let Womble adjust the in/out points onto I-frames).

Does anyone know if this is possible or has even been done? If not, which existing script might get me most along the way to creating a new one? The standard "Export EDL" script in Vegas outputs a very different result from what would be required to import to MPEG Video Wizard.

Nick,
what does Womble expect?
Can you post a sample here or email one to me?

Bob.

Hi Bob, Here's a small .wbl file that I output from Womble MPEG Video Wizard:
----

LTH 1.0 (there follow a couple of strange characters after this that can't be pasted here)

[Video]

----
There then follows a lot of strange stuff but if I can work out how to output the stuff between the [Video] and [Image] then that can be pasted into an existing wbl file and imported to Womble.

So it seems the string for each event is made up as follows:

Item=
Filename
*
Filename again without the extension
*
m2t (could be file type or file extension but it doesn't matter)
*
Frame number of "in" frame ("offset")
*
Frame number of "out" frame
*
0 (don't know what this is)
*
File counter (starting at 0)
*
-1 (don't know what this is but it looks consistent)
*
135266528 (don't know what this is but it looks consistent)
*
135528640 (don't know what this is but it looks consistent)
*
25.000000 (framerate)
*
1 (don't know what this is but it looks consistent)
*
Mysterious number - NOT CONSISTENT
*
Mysterious number - NOT CONSISTENT
*
Length in seconds of parent event before trimming
*
0 (don't know what this is but it looks consistent)
*
0 (don't know what this is but it looks consistent)
*

Note that my files were captured with HDVsplit and the filenames are of the format '20061101 15.54.19.m2t (so they work with my gearshift/sclive method).

A script would probably be pretty straightforward for someone who knew what they're doing. I just need to find out what those 2 mysterious numbers are that are not consistent. The later numbers in the string might be to do with the audio stream???

Anyone keen on experimenting with this can download a 30-day trial of MPEG Video Wizard from www.womble.com

EDIT: I have emailed Womble about this to find out how those lines are made up

Stuart,
"a better choice is VideoReDo"
With all the Wombling in this link, could I request that you expound a bit on VideoReDo?

Got a quick reply from Womble. This is promising:

Hello,

I'll tell them if they write a Vegas script to output a Womble trim list, they may well get themselves a substantial number of new sales.