VBR-Wav-CBR: interleave, preload, delay?

[Quantos]

Hello everybody,

I had some trouble recently with the editing of some AVI encoded with
VBR-Mp3 audio. Those AVI's (roughly 1GB in size, each consisting of
3 episodes of a TV-series which I want to seperate into smaller files).
So that's the starting point.

In order to avoid any sync-issues, I didn't go for the proposed Virtual-
dub-"VBR press no-button" method but did the following:

1: I decoded the VBR-audiostream (via V-Dub) into the Wav-format.

2: Then I saved the video (without sound, of course; basically I
demultiplexed the original AVI-VBR combo in a rather
cumbersome way :confused: ).

3: I multiplexed the "rough"-material (Video+Wav) in V-Dub. Afterwards
I made my editing.

4: Finally, I loaded the edited material in Vdub and encoded the
audio (via Lame) into CBR-Mp3.

Now, I did the whole (stupid? tiresome!) thing without paying attention
to any delay, interleave or skew values. Neither in the original AVI-VBR's
nor in my own "creations" (I think Vdub used it's standard values for them).
The values of the new files differ from the values of the source-AVI's. So,
did I make a "terrible" mistake and introduced a sync-problem all by myself
(if yes, I want the patents on it!) and do I really deserve the prize for
the most arduous and ineffective Vdub-usage so far?

All kinds of answers appreciated

Quantos

[CWR03]

In order to avoid any sync-issues, I didn't go for the proposed Virtual-
dub-"VBR press no-button" method but did the following:
You do need to press "no" in order for it to work properly.

I recently redid the audio on some files in the same way - instead of saving the video and remuxing later, I demuxed the audio and left VDubMod open while I transcoded the audio, then added the new audio and disabled the old and saved it using Direct Stream Processing. The only difference between your process and mine is that you'd be saving each of the three episodes afterward instead of the whole file.

[Quantos]

Hi CWR03,

of course you're right there. I have to push "no" with every VBR-file while
using Vdub-Mod in order to prevent it "fixing" the skew. But with the
"method" I was refering to a direct editing in Vdub-Mod, without
any demuxing or reencoding. Some say it works...

You said you did the same thing as I did (only far more elegant :p ). Did you
make any use or alteration of the skew, interleave, delay values while you
where processing your files? Do they play a role at all (in this specific task)?

When you demux the AVI-VBR file (which shows specific delay etc. values
in Gspot) and process the whole thing as described, you end up with new
values (Gspot again). As a matter of fact, If you multiplex the raw audio
with your video (as I did), Gspot shows none of those "Container-Values",
so those from the AVI-VBR seem to be lost/irrelevant.
If I reencode the edited material into CBR-Mp3, Vdub-Mod seems to apply
the standard values, which are of course different than the original ones.

So should I have applied the original delay etc.-values to the multi-
plexing-routine of the video and wav-audio? Is there a error in my (our)
way of handling "the situation"?

I'm still suspicious and very confused :sly:

Greetings

Quantos

[CWR03]

Try it the way I described - if the synch is off, check it to make sure it's equally off throughout the file. If it is, that's easily correctable.

[Quantos]

Hi CWR03,

the thing I really want to know is: how does the changing of the
preload/interleaving-options change the sync of my movies. Do they
delay and therefore desync my Avi-files? How can I avoid that? By
saving the original preload/interleave-settings? How can I do this in
my "custom-made" method of editing/reencoding?

Thanks (CWR03 ;) )

Quantos

[Quantos]

By the way, which program shows me the delay of my Avi-files. Avi-mux
shows me always "Delay-0ms", with every single file, and Gspot doesn't
seem to do it at all.

Thanks

Quantos