NTSC MPEG1 to PAL MPEG2 conversion. Possible?

[DRP]

I've got some downloaded TV show captures in NTSC MPEG1 (VCD) format. They are hardcoded to 29.97fps being as how they are American. My DVD player for whatever reason has a hard time playing and converting NTSC VCDs to my PAL only TV. It creates an annoying audio sync problem during playback. The same problem does not however occur on NTSC SVCD playback - weird huh?

Anyway, I can get by with re-encoding the MPEG1 into MPEG2 at NTSC and playing it. That works fine with just a little bit of jerky motion during panning scenes etc which I can easily live with. At least the audio remains synced which doesn't happen if I play it as a VCD.

What would be even better still is if I could convert the whole lot to 25fps instead. I know how to convert 23.976 to 25 easily enough, but how do I go about converting 29.97 to 25 in this case? I assume I have to do an 'inverse telecine' somewhere. Is it possible to do this on an already encoded MPEG1 file? Is the information about which frames to take out still in the file?

[DRP]

Sorry to bump but I have another question on this topic as well. If, as I suspect, it is not going to be possible to inverse telecine the MPEG1 @ 29.97 back so it can become an MPEG2 @ 25fps, then I can live with playing it as a 29.97 MPEG2 but what would be the best way to minimise the losses caused by another encoding?

Particularly I'm thinking about the unnecessary step of re-encoding the audio (which is already MP2 224kbps CBR in true VCD style). Should I do a simple de-multiplex in TMPGEnc of the two streams, re-encode the video portion only and then re-multiplex the new MPEG2 stream back together with the original MP2 audio stream?

Will that work?

[lordsmurf]

Test out a NTSC MPEG-1 DVD and see how it works. It may just be the NTSC MPEG-1 on CD, not the format itself (NTSC MPEG-1) that chokes.

[FulciLives]

Don't expect a NTSC VCD MPEG-1 to look good as a PAL MPEG-2 video (be it CVD, SVCD or even DVD).

But if you must ...

http://www.geocities.com/xesdeeni2001/StandardsConversion/

My experience is mostly with PAL to NTSC not vice versa plus I consider this basically worthless anyway since it ain't gonna look pretty so please don't bother me with questions on this.

- John "FulciLives" Coleman

[FOO]

The only way to do the IVTC on hard Telecine is
one of the Avisynth or Vdub filters which have to
take the frames apart and compare fields to see which are
duplicated. With MPEG1 it might be hard because of noise.
(impossible if it's 240 high)
If it's from a TV show it might actually be 30 fps , in which case
you are screwed .

edit: ...ok it's not the ONLY way

[lordsmurf]

Don't expect a NTSC VCD MPEG-1 to look good as a PAL MPEG-2 video (be it CVD, SVCD or even DVD).

But if you must ...

http://www.geocities.com/xesdeeni2001/StandardsConversion/

My experience is mostly with PAL to NTSC not vice versa plus I consider this basically worthless anyway since it ain't gonna look pretty so please don't bother me with questions on this.

- John "FulciLives" Coleman

Um... his source is MPEG-1, so it won't get any better by making it MPEG-2.

[FulciLives]

Um... his source is MPEG-1, so it won't get any better by making it MPEG-2.

Well that is what I am saying. At least trying to say ... sorry if it wasn't clear.

Thankfully I live in NTSC land and I say that because PAL converts fairly well to NTSC but NTSC doesn't convert as nicely to PAL because you are going up to a higher resolution whereas with PAL to NTSC you are going to a slightly lower resolution.

So NTSC to PAL never looks as good as the original NTSC on a NTSC TV display.

Of course a PAL to NTSC will not look as good as the original PAL on a PAL TV but it will look as good as NTSC can look so there is your advantage I guess.

All I know is VCD is shit to begin with so resizing it to PAL resolution MPEG-2 will make it look a lot worse.

- John "FulciLives" Coleman

[DRP]

Test out a NTSC MPEG-1 DVD and see how it works. It may just be the NTSC MPEG-1 on CD, not the format itself (NTSC MPEG-1) that chokes.

I only own one DVD. It's the BMW Films disc and it is NTSC. I seriously doubt however that it is MPEG1. On another point however even this one doesn't play properly in my DVD player. I haven't really investigated it properly yet but I get three displaced versions of the image on the screen simultaneously flickering like a badly adjusted vertical hold on the TV when I play it. I might just have a setting wrong on the player or something though because my player is definitely supposed to be able to play just about anything according to the manual.

[DRP]

Don't expect a NTSC VCD MPEG-1 to look good as a PAL MPEG-2 video (be it CVD, SVCD or even DVD).

But if you must ...

http://www.geocities.com/xesdeeni2001/StandardsConversion/

My experience is mostly with PAL to NTSC not vice versa plus I consider this basically worthless anyway since it ain't gonna look pretty so please don't bother me with questions on this.

Thanks. I'd already checked out that guide before posting my question, but it all looked much more complicated than I really wanted to get. I was hoping they'd be a way to do it almost entirely within TMPGEnc, but sadly I guess that isn't the case. No bother, I'll stick with the NTSC SVCD solution instead. It is perfectly watchable afterall in this format. Just a little bit of slight jerkiness in motion scenes is all.

[DRP]

Don't expect a NTSC VCD MPEG-1 to look good as a PAL MPEG-2 video (be it CVD, SVCD or even DVD).

But if you must ...

http://www.geocities.com/xesdeeni2001/StandardsConversion/

My experience is mostly with PAL to NTSC not vice versa plus I consider this basically worthless anyway since it ain't gonna look pretty so please don't bother me with questions on this.

- John "FulciLives" Coleman

Um... his source is MPEG-1, so it won't get any better by making it MPEG-2.

I fully understand that I can't make poor quality better by re-encoding. I'm not asking for that. I'm only trying to work around the limitations of my player's abilities whilst maintaining as much of the original quality as possible.

[DRP]

The only way to do the IVTC on hard Telecine is
one of the Avisynth or Vdub filters which have to
take the frames apart and compare fields to see which are
duplicated. With MPEG1 it might be hard because of noise.
(impossible if it's 240 high)

It is in fact 240 high (352x240). Why does that make it impossible?

[swede1]

Hello,

I just converted an NTSC VCD (MPG1) to a PAL DVD (MPG2) using Virtualdub and Tmpgenc with very good results (ofcourse the picture quality didn't improve) but audio stayed in sync and the percieved quality is equal to that of watching the original NTSC VCD possibly with some more jerky motion detectable.

Sitting at work right now I don't recall all the dirty details.
From memory I remember the procedure as:

1. Load the VCD MPG1 into Vitualdub

2. I did cut up the large MPG1 file into smaller sections (it consisted of music videos) using VirtualDub's feature of setting start and endpoints and then I saved each section in uncompressed AVI format (still in NTSC). The files become very large so have lots of time and diskspace at hand. You don't have to cut it, you could save the whole MPG1 to uncompressed AVI, but it will be LARGE !!!
An alternative here instead of uncompressed AVI is to use Virtualdub to convert it into a compressed format with little quality loss using a codec such as Huffyuv, where you'll get smaller file sizes and won't loose that much quality.

3. I then fed each uncompressed .AVI into Tmpgenc, selecting the output to PAL DVD and tweaking some settings for max possible quality (motion detection etc) which makes the encoding process SLOW but you'll loose little in quality.

4. Tmpgenc splits the resulting file output into a .m2v file (the MPG2 stream) and a .wav file (the audio). I think you can get tmpgenc to process it as one file but the advantage here is that you can load the wav into CoolEdit Pro and play around with sound quality and levels (have done this in other cases), just don't trim it or you'll loose sync.

5. Then I just authored the DVD in usual fashion (using tmpgenc DVD author), using each .m2v and it's corresponding .wav file.

Hope this works for you

[FOO]

If it's 240 high it doesn't have fields and
wasn't Telecined , so you can't Inverse telecine.