Capturing Star Wars LD to DVD - dialogue is muffled

[lchiu7]

Trying to capture Star Wars LD to DVD via Hauppauge WinTV PCI card. I capture in 720x480 Huffyuv 49khz 16 bit sound. I can capture one side with no frame drops. Then convert to mpeg2 with tmpgenc and author with DVD Video Factory and burn with the same or Nero (using DVD-RW). The resultant file plays fine on my PC. However on my DVD player, while the picture plays fine, the dialogue is really muffled. I thought that since the LD is Dolby Surround the dialogue is meant to be in the center channel but if I select the right audio options in the DVD player to do the Dolby downmix there should be no problem but no matter what I do with the DVD player sound options, the dialogue remains muffled. If I capture a mono LD the sound is fine

Any ideas?

Thanks

Larry

[TeeeRex]

What option are you using in tmpgenc to encode your sound ? stereo, joint-stereo or dual-channel ?

[lchiu7]

I think I am using stereo, well the default. I am going to try the other two options out of interest

It could be a DVD player issue. When I play the DVD on another player, it sounds fine. Sounds fine also on my DVD-ROM drive using PowerDVD. What I appear to be hearing is sort of like, the left and right channel sound with the center channel removed. However with the player that is having the problem, it's connected only via analogue connections to the stereo receiver so there is no center channel anyway. Plus the sound on the disk is MPEG2 since I have no software that can author AC3 sound.

Strange...

Larry

[lchiu7]

I just tried something else. Rather than use mpeg sound I use Besweet to create ac3 sound from the original avi file (actually ran the raw avi file through tmpgenc and selected PCM sound, then ran that wav file through Besweet to create an ac3 file). Then multiplexed and authored using Ifoedit. Same muffled sound on one of my players. On my other player which outputs to a DD amp, if DD is not selected the dialogue is centred okay. If I select DD mode, then the dialogue comes out of all channels which is strange. Guess the problem was not not using ac3 and something else so back to mpg sound?

Larry

[TeeeRex]

Pro Logic (surround sound) is encoded in the analogue 'stereo' wires so you will still get center, left, right etc as long as you have a Dolby Pro logic decoder (if you have a DD or DTS one, then assume it does this as well).

Pro Logic 'downmix' from AC3 is done at encoding stage by tmpgenc (via internal or external tools) so this should be fine and contain a correct Pro Logic analogue stream.

All I can suggest is to check the output settings on your DVD player and I would also turn off any 'AI' or sound enhancers on your TV, because these have been known to mess things up from time to time.

[dcsos]

disconnect the left or right channel from the laser disc
and capture a short bit again
If the sound is no longer muffled, its a good bet you're having PHASE and FREQUENCY dependent cancellation from interaction between the channlels!
by the way JOINT STEREO is TMPG's default

If the test works , to eliminate muffling please re-post and maybe we can help with a seperate audio capture method

[lchiu7]

OK - I feel a bit sheepish about this. I looked at the issue of being out of phase and so first thought my speakers were connected out of phase. No difference when I switched them but I happened to see that the amp mono/stereo button had been set to mono! (my kids!). Switching it back to stereo and the dialogue is fine Guess the sound source must be out of phase for the mono switch to cancel out the dialogue.

On the issue of ac3 sound, still not sure., My receiver has DD and Dolby Surround. DD goes in via the coaxial digital connection of course. However when using the DD input and the receiver is set not to do 5.1 sound, then all I get is the two front stereo channels (the DVD has been recorded with 2 channel DD). If I turn on the 5.1 processing then the dialogue comes out of all speakers (can't speak for the sub since I don't have one) which is strange also. But if I encode the DVD with mpeg sound instead so that the signal coming out from the DVD is analogue and therefore now going into a regular analogue input on the receiver, setting Dolby Surround gives me the same sound as I got when playing the original LD (which is Dolby Surround). Strange

Larry

[dcsos]

I think you should be so happy..The analog bump will be unnoticeable.
If you want, transcode back to Ac3 5.1
two authoring programs that take 5.1 mpeg and automatically make 5.1 ac3
1.Sonic Foundry DVD ARCHITECT
2. DVD LAB

glad the phase suggestion was sorta correct
..sorry they didn't test LD for mono compatible soundtrack :-)

[lchiu7]

Actually the problem isn't entirely solved yet. I did another test with tmpgenc creating a file using dual channel and stereo for the sound. And then burnt the DVD. When I play it through my Dolby Digital amp, but of course using analogue out from the DVD player since my player (and I suspect most) don't output a digital signal from the mpeg track), it sounds fine in stereo, but if Dolby Surround is selected (the original source from the LD was encoded in Dolby Surround) then the dialogue spreads across all 5 channels and Pro Logic sound is lost. I can understand if I had used Joint Stereo that might have happened since Joint Stereo supposedly destroys Dolby Surround information but not using Stereo or Dual Channel.

This is a bit strange

Larry

[dcsos]

I'll bet its cause the 5.1 is coming from analog MPEG that it speads the channel.
Woud a transcode to ac3 put everything out of sync?
I don't trust TMPG to turn off join stereo properly !

[lchiu7]

I have tried stereo and dual channel - both give the effect I described above. I also even took the raw avi file, extracted the audio wav file, ran it through Besweet to make an ac3 file (so avoided tmpgenc audio processing) and multiplexed back with the video. Still the same. Have no idea what is going one now

Larry

[dcsos]

You GOT ME NOW
don't have any more suggestions ready
Good Luck