Why DeMUX/MUX when Skipping Audio Resampling

[frogman709]

Tool is great but I have a hopefully not too lame question

Why does SVCD2DVD 1.5 still Demultiplex and Multiplex the mpg when it knows it's going to skip the resampling step because the audio is already 48khz?

I've been using TMPGENC to Normalize the Audio on a collection of TV Episodes and while it's doing that I've been having it resample. So SVCD2DVD skips the resampling but it still DeMUX/MUX's the file.

I bet it would real run quick without the extra processing. Of course if it could Normalize the Audio at the same time as resampling that would be even better! SVCD2DVD sure is easier to use than TMPGENC.

[ChrissyBoy]

At the moment it is assumed that you will be authoring using svcd2dvd. Therefore the mpeg needs a certain structure to hold DVD nav packs. To ensure that this is the case we demux & then mux to get that structure. In the next build: if the structure is already there it won't remux. This will allow you to use previously processed mpgs as sources for your dvd without the need to re-process.

If you are not authoring with svcd2dvd then maybe i should just skip the lot if you are @48Khz..... Thoughts?

In your case then you will not have the 2 private streams for nav packs so i must do the demux/mux thing. Bare in mind that most authoring packages do this also but it is part of their "authoring phase".

[frogman709]

Ahhh... that explains it. I knew there was a reason.

I personally like the authoring with SVCD2DVD so I'll continue as I have been. Skipping the demux/mux automatically when you skip resampling would suck but if you added a switch maybe someone/somewhere would use it, but not me? I do like the idea of skipping the remux for reprocessing though, that will be a time saver after abends.

I'm sure you'll include 'Normalize Audio' in SVCD2DVD sooner or later and I'll be able to skip the TMPGENC step altogether. Even without that SVCD2DVD is still my favorite way of processing/authoring mpegs!

While were working on my wish list though... a 'Play All' button on the DVD Menu would be a nice addition. Sometimes you just want to play the whole DVD without going back to the Menu. A Skip-to-next option for each VTS might be overkill but just the one extra 'Play All' option would be nice.

Thanks for the explanation!

[ChrissyBoy]

'Play All' sounds quite interesting...... I'll look into it.

[duhmez]

My thoughts: When 48 Khz audio, and when user chooses to create "program stream" then do not de/remux.
Preferrably choose "resample audio" but if it detects 48 khz, then it will just copy the file and name it file_dvd.mpg (Just so we know it has been looked after)

If svcd2dvd already refuses to resampele when already 48 khz audio, I was not aware and have been sorting everything manually myself before processing; one folder has files with 48khz audio and for that folder i choose not to resample etc.

[ChrissyBoy]

My thoughts: When 48 Khz audio, and when user chooses to create "program stream" then do not de/remux.
Preferrably choose "resample audio" but if it detects 48 khz, then it will just copy the file and name it file_dvd.mpg (Just so we know it has been looked after)

That could be an option.

If svcd2dvd already refuses to resampele when already 48 khz audio, I was not aware

Indeed. If audio is 48K then no resampling is performed whether you choose skip or not.