Resizing stripped AC3??

[aussiemac]

I have three Xvids that I am coverting to DVD.
They are episodes....so need to be separate.

Two of them have mp3 for sound.

So I convert using VirtualDubMod to big Wav then use AC3Machine to convert to AC3.

One already has 192KHz AC3 sound. So I just use VirtualDubMod
and Demux a direct stream copy....or do I ???

I have to put the three episodes on one DVD.

So I really should have the Audio as same AC3 and same 224Khz bitrate.

So my question is.. how should I convert the 192KHz AC3 to 224KHz bitrate???

Do I need to make a big Wav using VirtualDubMod... then convert
to AC3 with 224KHz bitrate with AC3Machine???

Or is there a simpler way of just converting the existing 192KHz AC3 to 224 KHz bitrate???

[jimmalenko]

So I convert using VirtualDubMod to big Wav then use AC3Machine to convert to AC3.

One already has 192KHz AC3 sound. So I just use VirtualDubMod
and Demux a direct stream copy....or do I ???

In all honesty, I don't think making the change between 192 and 224 is going to be of any benefit at all, because if you're not doing anything to the audio in the way of filters, you're obviously not improving the audio in any way (upping the bitrate don't improve jack - garbage in = garbage out remember), so it'd just be waste of time IMO. Just demux the 192 AC3 using Virtualdubmod then remux this into the converted video stream, just as you are the converted audio clips.

[aussiemac]

I understand what you are saying about not much improvement
in the audio quality ...

My main concern is when it comes to muxing the streams together
...then authoring the three episodes together

one will have an audio stream of 192Khz AC3
and the other two will have audio streams of 224Khz AC3

wont there be problems in authoring with this difference
in Bitrate???

as I am using one menu to control all three episodes

[jimmalenko]

My main concern is when it comes to muxing the streams together
...then authoring the three episodes together

one will have an audio stream of 192Khz AC3
and the other two will have audio streams of 224Khz AC3

wont there be problems in authoring with this difference
in Bitrate???

Nope. As long as each episode is it's own titleset, and you're not using your authoring software to join any of the clips together to make the one titleset, then you shouldn't have any issues whatsoever with the different audios.

[aussiemac]

Yeh see thats the problem I have been using just one title set for all
three episodes ...

It worked fine for previous DVDs ..but they were all using 224 KHz bitrate
...thats why I am asking what is the best way to change this
192 Khz bitrate audio to match the other two 224KHz audio soundtracks

Should I extract a big Wav from the AC3 using VirtModDub then use
AC3Machine to re-encode to 224KHz bitrate???

So all three episodes match each other as far as audio bitrate
...then I can put all of them under one menu and Video title set

as I have been doing previously

[jimmalenko]

Ahhhh, OK.

Two ways I can think of - open in Virtualdubmod and streams > stream list, extract the AC3 to a WAV, then re-encode in AC3Machine or ffmpeggui

OR
Load the AVI straight into ffmpeggui then convert to 224kbps AC3.

Once you've done either of these, open your AVI with VirtualdubMod, go to Streams > Stream List and delete the existing stream. Then click the Add button, and add your new AC3 stream. Go to Video > Direct Strem Copy and then File > Save As ... and save it out to a new AVI file. This won't touch the video (it'll just directly copy it into the new file), and attach the new audio stream to it also.

[aussiemac]

Thanks...jimmalenko!

Yeah I just wanted to make sure that was the best way
to redo the AC3 to a 224KHz bitrate

Using VirtualDubMod to extract a Big Wav then re-encode
to new AC3 224KHz bitrate using AC3Machine...

I appreciate you advice on how to change the audio for the
original Xvid and then rejoin Video and audio back together
to form the Xvid with new bitrate...

Thanks for you advice

[jimmalenko]

Thanks...jimmalenko!

I appreciate you advice on how to change the audio for the
original Xvid and then rejoin Video and audio back together
to form the Xvid with new bitrate...

Thanks for you advice

No dramas mate, here to help!

[aussiemac]

I just tried to strip a Big Wav out of the Xvid but it said
"No audiodecompressor could be found to decompress the source audio format"

I opened the audio in Gspot and it shows the audio stream
as the following:

ATSC/A-52 (Dolby AC3)

I forgot that this Xvid would have come from an HDTV source.

Sounds like this is still the original HDTV AC3 stream - just demuxed from
original capture and remuxed to new Xvid video part.

How can I get this source to Big Wav ...is there a filter that will handle
extracting ATSC (HDTV) AC3 audio??

Or another way of extracting a Big Wav from this HDTV AC3 audio???

I havent dealt with Digital TV sources before...

[Soopafresh]

Check out this Readme file:

"This is version 0.7 of an AC-3 ACM Decompressor for Windows. This makes it possible
to preview and decode AC-3 audio in VirtualDub (or any ACM client). Only
decompression is supported by the codec; it cannot compress to AC-3 audio
at this time."

http://fcchandler.home.comcast.net/AC3ACM/

[aussiemac]

Thanks Soopafresh ...giving it a go!!!

[aussiemac]

Thanks again Soopafresh...it worked fine!!...now have a Big Wav
and have used AC3Machine to convert to 224KHz AC3 to match other
episodes ...ready for Authoring with DVDlab

I am getting Digital TV Tuner Card soon ...I assume this will allow me to
also extract a Big Wav from a HDTV stream from any captures I do from this card??