View Full Version : Virtual Dub Woes

2005-08-23, 10:30 PM
I have been having this same problem for a while now; Everytime I try to reencode a MPEG-2 recording to AVI, the audio never sticks. Using MP3 as audio codec. It seems to just encode no audio, reguardless of what settings for the audio I choose. I have installed Lame MP3, and it still doesn't work right. Below is a screen shot of what I mean. Is there anyway I can find out what is happening(logs etc.)?

2005-08-23, 11:38 PM
Did you set your audio setting in Virtualdub to "Full Processing Mode", and set a compression? Also, for help on virtualdub and other video tools, head to www.videohelp.com

2005-08-24, 03:22 PM
Some MP3 encoders just don't work as advertised, or some versions of some encoders don't work with some versions of vdub, or some....you get the picture.
Your best bet for MP3 encoding, is to get different versions of LAME, and keep trying until it works.
The advice LilY0da gave is also valid.

BTW, what are you transcoding that's going to take 40 minutes? What video codec?
That seems extremely long...
Make sure you use CBR audio, not VBR!!!!

2005-08-24, 03:52 PM
That can also happen if the decoder isn't being handled right by vdub. If GB is set to use a specific decoder for the audio, but your default decoder can't handle it for some reason, it will encode and just drop the audio w/o an error.

Try previewing the input and output panes for audio, and see if it plays fine in media player (if the file is in a red text when you play, it's probably audio). You can also use gspot on the file to find out is something is assigned to handle the audio by deafult.

One last trick it to try to save the audio as a wav first, and then just use the wav on the full reencode as the source audio.

2005-08-24, 06:14 PM
I tried doing the same thing as last night, and it works! I really don't understand it, because I have been having this problem as long as I have been transcoding mpg's/vob's to avi format. The only thing that I can think of is I didn't reboot my computer (doh!) after installing the Lame MP3 codec.

To Reboot:
That was just a 720x480 30 minute show (1.4GB) I recorded. I was using Xvid with mild settings. This was just running the file directly into vdub. I was however deinterlacing, so that might have been the reason for it being so slow...AMD Sempron 2600+ @ 2400mhz w/ 1GB PC3200
EDIT: I started running the file through avisynth first, and it seems to run about realtime.

To Capone:
I was able to hear sound in the input/output preview panes, but when it came time to encode, it just wasn't there. Media player had no sound in it, but right clicking on the file >>Summary Tab>> indicated the correct bitrate and codec for sound. Weird. I did have warnings off in VDUB.

Oh well, I guess as long as it works its O.K. I'll have to keep checking it now to make sure it stays fixed.

Thanks for all the insight guys!


2005-08-24, 06:43 PM
Deinterlacing would slow it down!
Why deinterlace? Are you viewing exclusively on a monitor, or TV?

FYI, the audio may have been fine, but WMP can't decode it.
I never use WMP for anything.

2005-08-24, 09:19 PM
Deinterlacing would slow it down!
Why deinterlace? Are you viewing exclusively on a monitor, or TV?

Encoding for my Phillips DVP 642. Also, I noticed that if you don't specify in xvid that the video is interlaced(and having no intentions of deinterlacing) I usually get a bunch of artifacts around objects that move. Checking the box gets rid of the artifacts.

2005-08-25, 03:57 AM
I figured it out.
I decided to test the same situation out on my HTPC. It turns out that it wasn't the installing of the Lame MP3 codec afterall. At about the same time last night, I installed ffdshow on my computer. That's the program that I had to install to get it working on my HTPC. Same situation, same fix. Now, looking at the icon bar, I can see two little ffdshow icons as my HTPC encodes another episode.

@ Capone: Playing it in Media Player, the text was indeed red.

I guess the lesson learned here is:
When in doubt, REBOOT!