How do I improve audio quality using TMPGenc and Virtual Dub

[nille]

Hi, I´ve got a newbie question here.

I´ve followed the exellent guide on this site on how to convert a divx file to SVCD. Everything works fine, except for the fact that I´m not too happy about the quality of the audio. I´m using virtual dub and TMPGenc.

Can I do anything to improve it and what effect will it have on the size of the file?

I read somewhere that you could use an external encoder(too lame), but their homepage was unavailable right now.

I´d be thankful for an answer.

regards
Nille

[danib666]

what do you mean about not being happy with the audio quality?
do you mean it has a slight metallic sound behind it?
if so then there is an easy way round it, do not use the lame external thingy as that makes no difference. try this method instead as it gives perfect sound for me everytime 8)

the metallic sound is caused by tmpegencs crappy audio conversion (48khz(which most divx audio is in) to 44.1khz(which is needed for vcd/svcd)) to get round this you need to use dvd2avi to do the audio conversion for you then you can use a ready converted wav file for the audio hence loseing any sound imperfections tmpegenc would've caused

follow these steps

extract the wav from the avi using virtua dub by doing this:
file > open video file > then select your avi
audio > then select full processing mode
file > save wav
that will give you the extracted wav

next open dvd2avi and do the following:
audio > then select 48khz->44.1khz (ultra high) also select the normalisation option
file > process wav then select the wav file you just created thru virtua dub
then select the file again on the save screen (this will not overwrite the original file as it states in the new file name that it is a 44.1khz file)
don't change the next 2 screens unless you really know what you doing, i have never needed to change these thru any of the movies i have encoded, just ok the both of them

your audio file should now be being converted, this process normally takes roughly 45 mins to an hour on a 1.4ghz athlon for a full movie

if you have any problems contact me on danib666@hotmail.com and i can help a bit more whilst i am at home and have the programs in front of me

oh an if you feel like making this into a proper guide with screenshots an stuff feel free to do it, i've been meaning to do it for months but never have the time just give me some of the credit for it if you don't mind

[danib666]

oh and those steps will have no effect on the resulting file size
since you asked and i forget to mention it in the last post

[nille]

Thanks for all your information.
Your steps seem very clear and very easy to follow.
I´ll try it tonight and report back to you later.

regards
Peter

ps. Before the conversion started with dvd2avi something about"delaying" popped up on the screen. It said 0 and I didn´t change that. Was taht corect?

[nille]

Hi again!

I followed you steps, but can´t make it work. Maybe I´ve misunderstood something.
When I finally start the process it´s all over in a few minutes, and the result is a very small file.
There are a few boxes that pop up in the end, which you said I was just going to ok.
Have I got the following things right: I tick off the normalisation box, which is 100 by default and then there is something about input delay, by default O, which I didn´t change.

What have I done wrong?

Regards
Nille

[banjazzer]

Save out the wav in Virtualdub using Audio>full-processing mode, but first select Audio>conversion and choose 44100Hz. Leave the other setting alone. I always use this way to extract audio from DivX without any audio problems. There is nothing wrong with Virtualdub's audio conversion IMO. TMPG's is a bit suspect. 8)

[nille]

Hi!

Thanks for your help.

I´ve already been using your settings in virtual dub, but after I´ve encoded the movie with MPGenc the sound is very metallic.

Danib666 recommended that I use DVD2avi, but I can´t make it work somehow.

I´d be greatful if somebody could help me using DVD2avi.
Regards
Nille

[banjazzer]

mmmh! The usual reason for the metallic noise is letting TMPG resample from 48kHz to 44.1kHz rather than letting Virtualdub. Strange I never got this in several hundred encodes. Mebbe I've got cloth ears?

[nille]

Thanks for taking your time.
I don´t think it´s because you´ve got cloth ears, the sound is clearly metallic, so I must be doing something wrong.

Thanks anyway.
Regards
Nille

[danib666]

tmpegenc definatly gives out metalic sound when using audio from a 48khzwav, maybe you're just lucky or are not that fussy about you're audio
just search the forum and you will see loads of people asking for help with it, even on tmpegencs forum too
it took me ages to find a way round it an this was the only decent way i could find, i tried vdub and still that didn't work properlyi also tried several differnt exteral audio encoders for tmpegenc an it still was the same

nille i've replied to your mail you sent me we'll work thru it step by step that way if you want

oh and if you have a icq address or are on msn messenger mail me you details we can talk like that, it would be far easier

how small was the resulting wav file? it should have been roughly 900mb for a full movie

[banjazzer]

If you read more carefully, you will see I do not recommend using TMPG to resample. However, my ears, and the ears of many of my associates tell me that letting Virtualdub resample the audio is fine. 8) If you prefer another more complicated way, then fine. But it does not necessarily make it better.

If I thought there was a problem I would use SSRC to resample from 48kHz to 44.1kHz. This is preferred my some to DVD2AVI when decoding from DVD. And DVD2AVI is not universally recommended for normalising, either!

[danib666]

all i am saying is that the metallic audio problem does exist and virtua dub didn't cure it for me however i will say that it was better than tmpegencs audio
all i'm doing is offering an extra solution that cures it for the people who are affected by it and i have found this method to give me the best quality audio i can get
if virtuadub sorts the audio for you then don't do these extra steps, however if you find you are still getting the metallic sound then this is the way i have found to get round it.
maybe it's because i run my svcd's thru a full home cinema setup that i notice the metallic sound more

[banjazzer]

maybe it's because i run my svcd's thru a full home cinema setup that i notice the metallic sound more

I can't argue with that - I don't have a full home cinema setup. 8)

[danib666]

just read back thru the whole thread, an realised that i may seem a bit blunt in my responses

don't get wrong, it's not being rude it's being hungover an struggling with the english language from it

[banjazzer]

No problemo. 8) I spend most of my time on usenet, so I've developed a thick skin. It's probably what prevents me hearing properly.

[King-Of-DK]

Hey Danib666,i have exactly the same problem with my sound,it keeps getting all metallic.I have tried your guide here,and the result is the same,as when i just extract with vitualdub,and convert with TMPGenc.I have tried everything,but the result is always the same,metallic sounding sound.Is there another program one can use to convert the AVI files with?
I have been converting a lot of movies,so i know pretty much what i am doing,although i can not seem to correct this little problem,i am running Win XP professional.I have to say that the sound after conversion with DVD2AVI sounds great,so the problem is with TMPGenc

I have also tried to use external tools in TMPGenc.I have tried to use TOOLame for the conversion,and SSRC as sample rate converter.It seems however that TMPGenc uses its own SRC,even though i have specified external tools

[danib666]

i've tried using external encoders for tmpegenc and found that if the sound has anything to do with tmpegenc then it will still get the metallic sound
but i am a tad confused, as you said that you are still getting the metallic sound and asked what other programs you could use to cure it and then said that the sound from dvd2avi is great
could you explain a bit more as to what problem you've got?
cos to me it sounds like it may be the original divx thats the prob and not the sound conversion because dvd2avi definatly cures the metallic sound prob

[King-Of-DK]

Yes the Wav i create with DVD2AVI is good,but i still have to use the wav as audio source,when i convert my AVI,and it is in that process the audio turns metallic.
I have even tried to use Soundforge and downsampled the audio to 44100,and then convertet it to mp2 with toolame,then encoded the video alone in TMPGenc,then multiplex it together,the result is the same,no matter what i do,every time i use TMPGenc the sound gets metallic.that is where the other program question comes in,is there another AVI2SVCD/VCD converter out there??

So in summary all files are great to begin with,but if they so much as get in contact with TMPGenc,i get metallic sound.I think the problem is,that TMPGenc does its own sample rate converter,even though i specify external tools for the job..

[danib666]

i still use tmpegenc for the encoding, i just use my pre converted 44.1khz wav as the audio and the divx for the video
works fine everytime here, and for everyone else i have shown it
i'm still a tad confused, have you definatly set up the 48->44.1 khz bit on dvd2avi? and i take it you are using the converted wav in tmpegenc when encoding?

[King-Of-DK]

In DVD2AVI i have set the 48->44100 to ultra high,and enabled the normalization.When i convert the AVI,i ofcourse use the DVD2AVI converted wav as audio,but i still get metallic sound.I have tried everything i can think of,but nothing works.I appreciate you helping me..

[danib666]

hmm thats an odd one, i've never had one not work using that method
all i can guess at is that the original avi has dodgy sound try another avi (preferably one ripped by a well known ripping group) and see if that one works

[King-Of-DK]

There is nothing wrong with the AVI´s i have tried the method on both We Where Soldiers and Ice Age,i have also said that the Wav´s made with DVD2AVI sounds great,but when i convert with TMPGenc the new mpg has metallic sound.. Could it be that it is because i load templates in TMPGenc,instead of manually setting the parameters for each file? As i said earlier i think that TMPGenc compresses/converts sample rate even though i already have a 44.100khz file,that is why i get metallic sound.How is your setup in TMPGenc???

[danib666]

all i use is the standard templates for vcd or svcd in tmpegenc, using the converted wav from dvd2avi as the audio and the original divx as the video.
i do no other tweaks of any kind other than source range for making the the movie encode in 2 halves, and 2 pass vbr for the encoding method. although i never used those b4 and it still came out fine.
as far as i am aware tmpegenc doesn't try to convert the wav during encoding if it is already 44.1khz. so this makes your problem a tad odd
i would ask what version of tmpegenc you are using but i've used this method on nearly all of the releases so i doubt that would be the cause.
although i would suggest getting a fresh copy of tmpegenc and trying again, as you could have changed something in it whilst you were playing about trying to work out how to get rid of that sound (i know i messed my version up)
let me know how it goes with a fresh version of tmpegenc

[King-Of-DK]

Maybe that´s it,the 2 pass vbr,when i load a template it automatically set the bitrate CBR.If you choose 2pass vbr do you mess with anything else?? Like the VBV buffer size? What about your aspect ratio? If i install a completly new version,i cannot work with MPG 2/SVCD files,but i will give it a try..I have now installed the new free version 2.57,and installed the vfp plugin.

[banjazzer]

In DVD2AVI i have set the 48->44100 to ultra high,and enabled the normalization

For what it's worth, I use DVD2AVI 48->44100, but set to mid. And I also use another prog to do the normalisation. Maybe that accounts for why I don't get a metallic sound?

[King-Of-DK]

I don´t get the metallic sound till after conversion with TMPGenc..

[Scrooge]

Maybe I didny read the postings properly, and I am familiar with the type of metallic noise you are talking about. I have had it under 2 conditions. 1) 44100 conversion in Tmpeg and 2) The previous codec that my PC was using for audio decoding. In the second, I cant remember what I changed, but it would make a metallic noise on my PC playback, but not on my DVD player. I reloaded some codecs and it went away.
Maybe you have a similar problem?

[King-Of-DK]

I don´t think that is the problem,because i also have it on playback in my standalone.and if it where the codecs,shouldn´t the problem already show itself on playback of the original DIVX? I have now tried again with the DVD2AVI method by Danib666,and the problem still persists,although this time i used the 2vbr pass mode,nothing has changed..I still get metallic sound...Please guys what do i do? I am tired of this not working for me..

[danib666]

i'm not sure where you are getting the problem from, as the method that i use for my audio is exactly step by step as i showed earlier
the 2 pass vbr will not make any difference to it nor will any other settings to do with the encoding, as i used to just encode normally (cbr) not using any extra settings or bitrate adjustments and the audio still came out perfect
the only thing i can think of at the moment that is different is that you have installed the vfp plugin, but again that should'nt make a difference as i'm sure other people in here would have that installed too.
i don't suppose you have a lot of codec packs installed by any chance?

[King-Of-DK]

Yep,i have them all divx 3.11 divx 5.02,OGG, AC3 and some others