AVI to VCD using Tmpgenc - poor sound quality

[cyaw]

I am using Tmpgenc to convert ACI files into VCD files. While the video quality is OK, the audio quality sounds like it is coming out from cheap speakers. I have tried extracting audio into a WAV file separately and then combining it but it still gives the same poor quality. Any clues, anyone?

[vitualis]

TMPGEnc's native audio encoding isn't very good. However, you can use toolame as a plug-in for TMPGEnc. This yields excellent quality audio.

Regards.

[cyaw]

Thanks for the advice, virtualis. I'll give it a shot!

[Lamont Cranston]

<TABLE BORDER=0 ALIGN=CENTER WIDTH=85%><TR><TD><font size=-1>Quote:</font><HR size=1 color=black></TD></TR><TR><TD><FONT SIZE=-1><BLOCKQUOTE>
On 2001-08-29 23:13:07, vitualis wrote:
TMPGEnc's native audio encoding isn't very good. However, you can use toolame as a plug-in for TMPGEnc. This yields excellent quality audio.

Regards.

</BLOCKQUOTE></FONT></TD></TR><TR><TD><HR size=1 color=black></TD></TR></TABLE>

Michael, is it necessary to re-encode the AVI with Toolame installed or can I demux, process and remux?

[JTurbo]

Ive actually found that TMPGenc audio ENCODER is not too terrible, its actually its audio DECODER. I started capturing all my AVIs with uncompressed wav audio, and when using this source to TMPGenc instead of an mpg audio source, i get FAR better audio quality (no pops, clicks, etc).

Scott

[cyaw]

To date I have tried:
1. Using tmpgenc's own audio encoder;
2. Extracting a wav file from the avi file using virtualdub
and then using the wav file as the audio source;
3. normalising and EQing the wav before using it as the
audio source; and just last night;
4. using toolame as the audio encoder in tmpgenc; and
5. using the original and normalised extracted wav files
for encoding by toolame in tmpgenc

They all lead to the same poor audio quality - if the levels go high the sound becomes metallic. The audio quality of the original avi file and the extracted wav files is fine. It's only when it gets encoded that the sound gets degraded.

I have tried reinstalling the sound card (SB live! value) drivers too.

I'm game for anything, folks. Any ideas?

<font size=-1>[ This Message was edited by: cyaw on 2001-08-30 19:45:14 ]</font>

[vitualis]

<TABLE BORDER=0 ALIGN=CENTER WIDTH=85%><TR><TD><font size=-1>Quote:</font><HR size=1 color=black></TD></TR><TR><TD><FONT SIZE=-1><BLOCKQUOTE>
On 2001-08-30 04:29:48, Lamont Cranston wrote:

Michael, is it necessary to re-encode the AVI with Toolame installed or can I demux, process and remux?
</BLOCKQUOTE></FONT></TD></TR><TR><TD><HR size=1 color=black></TD></TR></TABLE>

I assume that you still have the original AVI?

You could just load the AVI into TMPGEnc (with toolame installed) and encode it as "audio only".

Or, extract the audio as wav from the AVI and manually encode the wav to MP2 with toolame (i.e., using the command console). I would personally do it this way -- but probably only because I have an unreasonable dislike of TMPGEnc... Either way is fine.

I take it you've already encode an mpeg with TMPGEnc from the AVI? You could demux that mpeg to the elemental video and audio stream. Ditch the old audio stream. Now, multiplex the video and new audio streams together.

@cyaw: is the audio originally in 48 kHz and you are encoding to 44.1 kHz?? If so, you may want to use another proggy to do this... There is one available that you can plugin to TMPGEnc (I can't remember what it's called, but you can get it from doom9's site).

Or, you could use a proggy like CoolEdit to do a proper 48 --> 44.1 kHz downsample.

If this is not the issue, what does the original audio sound like?

I've used toolame by itself many times to encode MP2 and it is probably one of the best quality MP2 encoders (at VCD bitrate).

Regards.

[Snoopy007]

if ur original audio wasn't in 44.1khz, it will sound really tinny/metallic/bad once u use tmpgenc to convert it.

tmpgenc seems to lack a frequency resampler.

so I just use a plugin to resample to frequency. The program I use is SCMPX

[Lamont Cranston]

<TABLE BORDER=0 ALIGN=CENTER WIDTH=85%><TR><TD><font size=-1>Quote:</font><HR size=1 color=black></TD></TR><TR><TD><FONT SIZE=-1><BLOCKQUOTE>
I would personally do it this way -- but probably only because I have an unreasonable dislike of TMPGEnc... Either way is fine.
</BLOCKQUOTE></FONT></TD></TR><TR><TD><HR size=1 color=black></TD></TR></TABLE>

Michael, thanks for the info. The avi was encoded at 44.1 KHz and the mpeg audio track sounds tinny. Is the problem with TMPGEnc the audio encoding or the frequency down sampling from 48 -> 44.1 KHz?

If TMPGEnc is not your first choice as a encoder what do you use and recommend?

Thanks again.



<font size=-1>[ This Message was edited by: Lamont Cranston on 2001-08-31 12:37:45 ]</font>

[vitualis]

TMPGEnc's audio encoding isn't very good and it's downsampling is pretty bad too.

However, you don't need to downsample, you can just use toolame to encode the audio to MPEG-1 Layer 2 audio.

You can use toolame by itself (command console tool -- and you will need to extract the audio as WAV from the AVI first)...

OR you can use TMPGEnc with toolame installed and encode audio only (TMPGEnc will then defer the job of encoding the audio to toolame so functionally you do the same thing as the above method).

toolame is a very good MP2 encoder.

Regards.

[Lamont Cranston]

Michael, would you recommend VirtualDub, TMPGEnc ... to extract the wav file? [I extracted the wav from the avi with VirtualDub and TMPGEnc.The file lengths were a few bytes different and the media length reported by properties was .001 sec different. When I looked at both files with Cool Edit Pro both were the same length.]

Given all these audio problems based on your experience what would be your first choice for a mpeg encoder?


<font size=-1>[ This Message was edited by: lamont cranston on 2001-09-01 05:33:17 ]</font>

[vitualis]

I'm not entire sure what you are asking...

To extract the audio from an AVI (that is, output it as uncompressed PCM WAV), I would use VirtualDub.

To encode an uncompressed PCM WAV file to MPEG-1 Layer 2 audio (compatible with VCD), I would use toolame.

In terms of a 0.001 second difference, this is irrelevant. One video frame (PAL 25 fps) takes 0.04 seconds. I doubt you would be able to tell the difference in a one frame A/V sync error. You will definitely not be able to tell a 0.001 second difference.

Regards.

[Lamont Cranston]

I don't want to beat this thing to death but to claifiy my point I was surprised that the wav file length and time turned out differently with VirtualDub and TMPGEnc with the process being digital extraction. I recognize the 0.001 second difference is not a problem.

The second question related to a comment you made in an earlier post where you said "but probably only because I have an unreasonable dislike of TMPGEnc...". I just wondered expand oh the dislike for TMPGEnc, and if so, what would be your alternative choice?

[dysfunctional]

i am using toolame, and getting a message stating "an error has occured when audio decoded?


please advise! thanks

[vitualis]

<TABLE BORDER=0 ALIGN=CENTER WIDTH=85%><TR><TD><font size=-1>Quote:</font><HR size=1 color=black></TD></TR><TR><TD><FONT SIZE=-1><BLOCKQUOTE>
On 2001-09-02 10:36:48, Lamont Cranston wrote:
I don't want to beat this thing to death but to claifiy my point I was surprised that the wav file length and time turned out differently with VirtualDub and TMPGEnc with the process being digital extraction. I recognize the 0.001 second difference is not a problem.</BLOCKQUOTE></FONT></TD></TR><TR><TD><HR size=1 color=black></TD></TR></TABLE>

I'm surprised too... but then, TMPGEnc isn't specifically an AVI editing proggy. I would presume that VirtualDub would be more accurate. Perhaps it is simply an issue of how the headers were written (?? speculation).

<TABLE BORDER=0 ALIGN=CENTER WIDTH=85%><TR><TD><font size=-1>Quote:</font><HR size=1 color=black></TD></TR><TR><TD><FONT SIZE=-1><BLOCKQUOTE>The second question related to a comment you made in an earlier post where you said "but probably only because I have an unreasonable dislike of TMPGEnc...". I just wondered expand oh the dislike for TMPGEnc, and if so, what would be your alternative choice?</BLOCKQUOTE></FONT></TD></TR><TR><TD><HR size=1 color=black></TD></TR></TABLE>

Oh, okay. TMPGEnc is a pretty good MPEG-1 encoder and for something that is free, you can't really ask for much more. My "unreasonable dislike" is just that, "unreasonable". However, a lot of people have posted problems with TMPGEnc and I believe that the problem is partly because some of the settings in TMPGEnc are put in a funny way. Also, the default VCD templates in TMPGEnc aren't actually fully compliant (which continues to irritate me).

IMHO, for VCD standard MPEG-1, I believe that the Panasonic MPEG Encoder delivers better quality (from a perfect source, and without using filters -- which you shouldn't be). BTW, I don't want to get into another debate with those people who think TMPGEnc is better. Please just be open minded enough to realise that video quality (especially at VCD bitrates) is subjective.

Also, the Premiere plug-in version of Panasonic is just simply more convenient -- I use Premiere and FlaskMPEG quite a bit.

Regards.