25fps AC3 -> 23.976fps MP2 in BeSweetGUI?

[Xesdeeni]

Forgive me my ignorance, but BeSweet has quite a steep learning curve when you aren't familiar with all the other stuff it uses (Azid, Lame, etc.).

Latest stable BeSweet (1.4). Latest BeSweetGUI (v0.6 b60).

I've tried a couple of methods, but I can't seem to convert the framerate and sample rate at the same time. When I check the "Presets:" box and choose "PAL->NTSC (25.000 to 23.976)" from the pulldown, it goes through one pass (I assume it's converting from 48KHz to 44.1KHz...although wouldn't the quality be better if it did this after is converted the frame rate?) and then fails.

Here is the log file:

BeSweet v1.4 by DSPguru.
--------------------------
Using azid.dll v1.8 (b825) by Midas (midas@egon.gyaloglo.hu).
Using Shibatch.dll v0.2 by Naoki Shibata & DSPguru (shibatch.sourceforge.net).
Using MP2enc.dll v1.129 (23/5/2002), Engine 1.129 <http://www.cdex.n3.net>.

Logging start : 10/11/02 , 10:58:32.

c:\Program Files\BeSweet\BeSweet.exe -core( -input c:\Temp\Test AC3 T01 2_0ch 192Kbps DELAY 0ms.ac3 -output c:\Temp\Test(NTSC).mp2 -logfile C:\Program Files\BeSweet\BeSweet.log ) -azid( -n1 -c normal -L -3db --maximize ) -ota( -r 25000 23976 ) -ssrc( --rate 44100 ) -2lame( -m s -b 224 -e )

[00:00:00:000] +------- BeSweet -----
[00:00:00:000] | Input : c:\Temp\Test AC3 T01 2_0ch 192Kbps DELAY 0ms.ac3
[00:00:00:000] | Output: c:\Temp\Test(NTSC).mp2
[00:00:00:000] | Floating-Point Process: Yes
Error 46: Invalid combination between SSRC values & FRC values.
Quiting...
[00:00:00:000] Conversion Completed !
Logging ends : 10/11/02 , 11:00:25.

Xesdeeni

[DSPguru]

as stated in BeSweet FAQ, not all combinations are offered.
the only thing i could suggest to you is to avoid downsampling to 44.1khz.

[Xesdeeni]

VCDs require a 44.1KHz sample rate, while DVDs provide 48KHz audio. When you add PAL to NTSC conversion on top of this, you need to do both at the same time.

I thought (and being new to this, means I'm usually wrong when I think) the whole idea behind BeSweet's use of these other modules was to allow any one to feed into any other and do whatever you wanted.

I guess I can do this in two pass though:

1. 48KHz AC3 (PAL) -> 48KHz WAV (NTSC)
2. 48KHz WAV -> 44.1KHz MP2

Right?

BTW, couldn't both of these be done together by resampling the audio to a 42293.664Hz (48KHz * (23.976/25) * (44.1/48)) sample rate and then telling the mp2 encoder that it was really 44.1KHz?

Xesdeeni

[DSPguru]

Originally posted by Xesdeeni
VCDs require a 44.1KHz sample rate, while DVDs provide 48KHz audio. When you add PAL to NTSC conversion on top of this, you need to do both at the same time.you can safely use 48khz audio streams in your svcds.
after all, you'll be using modern reciever & player that capable of playing dvd streams.

BTW, couldn't both of these be done together by resampling the audio to a 42293.664Hz (48KHz * (23.976/25) * (44.1/48)) sample rate and then telling the mp2 encoder that it was really 44.1KHz?this could work, but it would be hard to find a resampler that supports this ratio 48000/42293.664 .


why won't you try encoding with 48khz ?
i believe it'll work.

[Xesdeeni]

I hate to say this (espcially in public--because it is likely that I will not actually finish and post this work), but with my (perhaps temporary) passion for standards conversion, and the constant questions I see here and on VCDHelp about how to do it, I'm trying to create a guide that covers all the combinations. The trouble is that I have to put my money where my mouth is and actually do each conversion (many of which I've never had the need or desire to do). (So, don't hold me to it. :-) ) Until now, I've concentrated on the missing link of interlaced video to interlaced video with my AVISynth script and the ported SmoothDeinterlace plugin. Now I'm working through the other combinations:

PAL VCD, Film SVCD, Video SVCD, Film DVD, Video DVD, progressive DV, interlaced DV, film on video tape, and video on video tape.

to/from

NTSC VCD, Film SVCD, Video SVCD, Film DVD, Video DVD, progressive DV, interlaced DV, film on video tape, and video on video tape.

Most DVD players don't support SVCD, and the VCD standard requires 44.1KHz. I'm not personally averse to 48KHz, and I'm aware that many DVD players can deal with 48KHz VCD content fine, but in the interest of accuracy, I have to get to 44.1KHz for the VCD destinations.

So I guess for purposes of this conversion, I'll have to use a two-step conversion. Bummer.

Xesdeeni