NTSCFilm 23.976 to NTSC 29.97 conversion

[brtomkin]

Hi. This question has probably been answered before, but I can't find it... so here goes:

I have an Xvid file with 23.976 fps and I want to convert it to MPEG-1 video. I have tried keeping the same framerate, but TMPGenc DVD Author will not accept 23.976 framerate. So, I assume I need to convert to 29.97, correct? Are there any special settings I need when using TMPGenc?

I am making a DVD using mpeg1 video. I can't use mpeg2 because it takes too long to encode on my computer and because I have not had much luck playing it on my old stand alone DVD player.

Any help would be much appreciated!

Brian

[Baldrick]

have you tried convert to mpeg2 (23.967 3:2pulldown) with some other encoders like mainconcept mpeg encoder, much faster than tmpgenc. cause converting to 29.97 is not a good idea.

[brtomkin]

I tried the Mainconcept Encoder 6 months ago and it still took around 4 - 6 hours for 1 hour of video. I also tried Xilisoft Video Converter and I couldn't get the mpeg2 video to work for me. I don't want poor video though, so I might just settle for the long processing time.

I don't know much about 3:2 pulldown, but is it possible to use this on mpeg1 video or is that only available to mpeg2?

Thanks!

[ofbarea]

Actually TMPGEnc DVD author will accept film frame rates as log as all MPEG files are film. TMPGEnc will not allow you to mix film and NTSC frame rates.

[kburton]

23.976 -> 29.97 framerate conversion is actually done on-the-fly by the decoder (your DVD player). You should not do this conversion during the encoding process, but rather set the 3:2 pulldown flag on the encoder.

[Baldrick]

3:2 pulldown is not supported in mpeg1....or you can probably add it but it is not dvd compliant.

[bugster]

If you are encoding to mpeg-1, I assume you are useing 352x288. Why not use the same res, but use mpeg-2 with 3:2 pulldown. I believe this is still DVD compliant (someone correct me if I am wrong!)

[freebird73717]

If you are encoding to mpeg-1, I assume you are useing 352x288. Why not use the same res, but use mpeg-2 with 3:2 pulldown. I believe this is still DVD compliant (someone correct me if I am wrong!)

This is what I would do. It is still dvd compliant and will look a whole lot better than mpeg 1.

[brtomkin]

My only reason for not using mpeg2 is the long processing time. It takes 6+ hours of computing time to do 1 hour of mpeg2 video (SVCD settings) on my computer.

[freebird73717]

Video takes a long time...especially with tmpgenc. Just set up the video to encode before you go to sleep and it will be ready when you wake up.

[Machine514]

I have patched a MPG1 23.976 to MPG1 29.97 and then burnt to a VCD-DVD and then repatched to 23.976 and it worked like a champ. Use a DVD+/-RW to test!

-Machine

[bugster]

My only reason for not using mpeg2 is the long processing time. It takes 6+ hours of computing time to do 1 hour of mpeg2 video (SVCD settings) on my computer.

Mpeg-1 Vs Mpeg-2. If you keep the reolution and bitrate the same, processing time should be pretty much the same.

VCD (MPEG-1) is 1150Kbit/s, 352x288.
SVCD (Mpeg-2) is 480x480, usually VBR up to approx 2500kbit/s. Much more data to generat hence it takes longer.

But, if you create an mpeg-2 with 1150Kbit/s, 352x288, it will take the same length of time to encode as the mpeg-1, and you can use 3:2 pulldown to convert your 23.97fps to 29.97fps, and it is DVD compliant.

In general, if you want to encode things faster you have a few choices.

1) Get a faster computer, especially CPU
2) Use a faster encoder. TmpGenc produces great quality but is slow. Most other encoders are faster
3) Accept lower quality. Using a lower bitrate/resolution means less data has to be generated so less time is taken to produce it. Of course quality suffers as a result.
4) Be more patient! Encode overnight so the wait doesn't seem so bad!

[brtomkin]

Thanks for the hints. I think that the best thing for me to do is just learn to be patient... that way I will end up with the best quality video. I never thought about the bitrate in that way. Every time I tried mpeg2, I was using SVCD settings, so maybe I will trying lowering the bitrate... a little.

Also, I was intrigued by the idea about patching the mpeg to a different bitrate. I have tried that with the resolution... to put some SVCDs on DVD without re-encoding the video and that has worked great. How good is the compatibility when patching the bitrate?

Thanks!

[bugster]

How good is the compatibility when patching the bitrate?

Thanks!

patching the bitrate will have absolutley no effect. The player will only play what is there.

If you mean patching the framerate, then I would expect compatibility to be, shall we say, patchy