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beerbaron
7th July 2002, 04:05
sorry ive read teh advanced ref for dvd2svcd but I'm still unclear about something. Is joint stereo always a better option than jsut plain stereo or would a certain scenario call for one or the other?

TIA

gerti67
8th July 2002, 15:13
Hi beerbaron,

if you want to have a Dolby Sourrond Pro Logic compatible Stereo (4.0) Downmix then you have to choose "Stereo" because in "Joint Stereo" mode this is not possible as it destroys the surround information.

Joint Stereo is the way to go if you only want Stereo - it can "shift" additional bitrate to the desired channels on the left and the right when there's for example only sound on the right and nothing on the left so it does not make sense to encode the "empty" channel with the same bitrate as with the other one.

Hope this helps,
Gerti

pacohaas
8th July 2002, 17:18
but mp2 js encoding is far from perfect and even at low bitrates (eg, 96kbps) stereo will sound better than joint stereo so basically there's no reason to use js in mp2's right now. Until they put as much work into it as the LAME developers did, it will introduce some unwanted artifacts.

ux-3
8th July 2002, 17:36
What about a mono source?

UltimateDBZ
8th July 2002, 20:16
If you have a mono source then there would obviously be no benefit in going to stereo or joint stereo, or anything other than mono.

DSPguru
8th July 2002, 21:46
in fact, LAME's joint-stereo is different than and mp2enc&tooLame's joint-stereo and will Always be better.
if you'll search for an old thread here, you'll find out that mp2 joint stereo is actually intensity stereo.

pacohaas
8th July 2002, 22:14
Originally posted by UltimateDBZ
If you have a mono source then there would obviously be no benefit in going to stereo or joint stereo, or anything other than mono. unless you're using the BeSweet mono2stereo extrapolation plugin, in that case i'm not sure whether this "intensity stereo" would be ok or if it's still best to use stereo...DSPguru?

DSPguru
8th July 2002, 23:49
when using the extrapolation plugin, joint-stereo is the way to go.

ux-3
9th July 2002, 00:35
Can this be done with dvd2svcd? I still seek a solution for my B/W mono movies...
Didn't find the plugin on your page. Whats it called?

pacohaas
9th July 2002, 00:49
just use mono

DSPguru
9th July 2002, 00:58
http://dspguru.notrace.dk/effects.html

Mono2Stereo v0.3

ux-3
9th July 2002, 09:10
thanks dspguru,

at pocahaas: There is no mono setting in DVD2SVCD, is there?

pacohaas
9th July 2002, 23:42
i thought there used to be, but it looks like it's not there anymore, but just copy the BeSweet command-line from the dvd2svcd log and paste it to a batch file, changing m s to m m, then run the batch file. As I've suggested before, check the "edit avs file" so the process stops to give you a chance to do the audio manually.

ux-3
15th July 2002, 00:32
Ok,
after downloading the plugin and reading the bypack sheet, I still feel somewhat lost.
Here is what I am up to: I have a DVD with a single Dolby Digital 1.0 audio track. I want to keep the bitrate very low. I have set to Joint Stereo at 96, hoping that it might be comparable to stereo at 192.

If I don't get any replies, I will run a besweet gui and convert the ac3 to mono, then replace files and restart with muxing and see what happens. Encode will need about 6 hours anyway.

I am trying to figure out what that plugin would do? Double data rate by creating a stereo from Mono? Or feeding two chanals from one data chanal?

indoboy
17th April 2003, 04:03
Hi all,

This is the first time I post.

My self still confuse which sound is the best. :confused:
But for the safety and good finished, I will stick with stereo.

Here the informations I found from the net about stereo and joint stereo.
Hopefully is usefull for you guys...

http://docs.real.com/docs/xingtech/acat_t_guide.pdf

http://www.modatic.net/audio/stereo_vs_jointstereo.php


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- ...keep singing... -
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zedstrange
8th June 2004, 14:52
Originally posted by pacohaas
just copy the BeSweet command-line from the dvd2svcd log and paste it to a batch file, changing m s to m m, then run the batch file.

Thank you for this answer - I know its an old thread but its what i need to help me. I am using DVD2SVCD to convert a captured TV Program with Mono sound.

Anyway I tried this solution above and it does not work for me. the result is that the Encoded MP2 file is exactly half the length of the Extracted WAV and has the 'chipmunk' sound. (in other words no change). I know how to manually solve this problem before using DVD2SVD but i would prefer to use the least amount of steps as possible.

Here is the content of my Batch file;
"C:\Program Files\DVD2SVCD\BeSweet\BeSweet.exe" -core( -input "D:\videocaptures\Extracted_audio_1.wav" -output "D:\VIDEOC~1\Encoded_audio_1.mp2" -logfile "D:\VIDEOC~1\Encoded_audio_1.log" ) -ota( -g max ) -shibatch( --rate 48000 ) -2lame( -e -b 96 -m m )

as you can see i changed "-m s" to "-m m". So it seems that there needs to be another option included or change and that is beyond me?

Thankyou.

Nick
9th June 2004, 19:08
I can't reproduce this. I tried a mono wav file with your commandline, only changinf the input and output paths and ended up with a perfect mono mp2 stream.

May sound painfully obvious but does the extracted audio.wav file sound OK or have you only checked the original capture file and the encoded audio file?

Basically I saved the audio from a 1-min avi I have out of vDubMod, converting to mono. Since BeSweet worked fine on that you might want to try saving the audio from your file as a wav out of VDubMod and running your commandline on that.

zedstrange
10th June 2004, 16:25
Originally posted by Nick
I can't reproduce this.
Thanks Nick. That would be becuase your source wasnt the exactly same as mine. I was actually capturing at 44100khz, and this was the root of the problem and other weird things as i tried to work around it. Never considered this before as i just used what Virtual Dub defaults to.

Have recaptured at 48000khz and its OK now, and I can run my batch file (as prev quoted) and it does the Job. Except that this has caused a noticeable interlace problem. Not a strong point for me, so time to go back to the search button. mIght try swap fields in capturing or Telecide in DVD2SVCD. cheers