Low volume when loading external audio file in VD

[danswano]

Hello,

When i load an external audio file .ac3 into a video loaded inside virtualdub, although the original file audio is loud, it becomes inside vd very low.
So when i save the avi as "direct stream audio" i get the same loud audio but the problem lies if i do full processing for the audio.

the result of the full audio processing is a low volume audio track as i mentioned above.

What's wrong? why i can't get the same audio after full processing?

Thanks.

[davexnet]

Full Processing implies you're converting it to something else. Perhaps there is a downmix involved and this will
likely involve different volume levels as you are seeing.

[danswano]

What to do to get the same volume level of the original ac3 file?

[davexnet]

I've usually used the mixer in FFDshow to do the conversion. Are you converting ac3 5.1 to two channel?

[danswano]

It's the ac3 track from my DVD's, most of them is 5.1 but not sure what is the output.

[davexnet]

When you do "full processing" in VD, what are you changing it to?

[danswano]

demuxed DVD mkv into xvid mpeg 4 avi.

[davexnet]

Yes but what about the audio - mp3?

[danswano]

<No compression (PCM)>
should i use compression?

[davexnet]

PCM is fine if you like uncompressed; I usually use Lame mp3, but that's my preference.

Here is a method I've used before with usually good results, perhaps you can try it.
If you have ac3filter installed temporarily uninstall.

Install FFDshow and Avisynth.
Check if FFDshow is set up properly, the mixer should look like this (see below):

Create a simple one line script in Notepad like this (substitute the correct path/file name for your movie) :
directshowsource("c:\your_path\your_movie.mkv", video=no)

Save this script to Desktop with a name such as aud.avs (make sure it doesn't get saved as *.txt as
notepad usually does)

Open your movie in Virtualdub and setup the video as you do now.
For audio, select Audio/"Audio from other file" and the select the .avs file saved from the script above.
also set audio to "Direct Stream Copy"

Save your movie in the usual way.

[El Heggunte]

............

If you have ac3filter installed temporarily uninstall.

No need for uninstalling AC3Filter, setting its merit to DO_NOT_USE (0x00200000) is sufficient.

[danswano]

Seems like a good method davexnet, i used to load the mkv files into VD using the avs script and directshow but had few bugs so i switched to FFMS.
I will try to load the audio using the same method you mentioned above but i have a question.
Can i do the same using FFMS instead of directshow?

[davexnet]

Can i do the same using FFMS instead of directshow?

You'll have to try it. I've had good luck with hybrid source such as this:

Audio = DirectShowSource("F:\Documents and Settings\Dave Xnet\Desktop\test_clip.avi", video=false)
Video = FFVideoSource("F:\Documents and Settings\Dave Xnet\Desktop\test_clip.avi", track=-1, seekmode=0)


The main problem is, if you use FFaudiosource for the audio, it will not go through the FFDshow mixer

[danswano]

Thank you very much davexnet,
I will try your methods and get back to you if anything went wrong.