how would u convert an mpeg-1 from 23.97fps to 29.97fps?

[hitechjunkie]

i am trying to convert my low rez, low bitrate mpeg-1 XVCDs, from 23.97fps to 29.97fps to get away from the video stuttering problem i am seeing when playing them back on my JVC standalone. i am keeping the same rez and bitrates, just changing the framerate. this is what i am doing:

1) demultiplex 23.97fps mpeg-1
2) load 23.97fps m1v file in tmpgenc
3) encode to mpeg-2, 3:2 pulldown on playback
4) load mpeg-2 m2v file in tmpgenc
5) encode to mpeg-1 29.97fps
6) multiplex 29.97fps m1v file with mp2/soundtrack file

i tried encoding the 23.97fps mpeg-1 directly to 29.97fps by using the 3:2 filter in tmpgenc, but not only does it reconstruct frames but fields as well which ultimately introduced really bad interlacing artifacts in the progressive-only mpeg-1. it be nice if i could enable the 3:2 filter but disable the fields portion of it.

anyone know of a method which requires only one re-encode instead of two which produces a smooth playing 29.97fps mpeg-1 from a 23.97fps mpeg-1?

[AntnyMD]

What is that recompression to MPEG-2 then recompression back to MPEG-1 doing to the quality of your video?

Surely there must be a way to frameserve your demuxed m1v back into TMPGEnc for re-encoding to MPEG-1. Have you tried to click on 3:2 pulldown in the Advanced tab? I've never used it; I'm guessing.

[hitechjunkie]

<TABLE BORDER=0 ALIGN=CENTER WIDTH=85%><TR><TD><font size=-1>Quote:</font><HR size=1 color=black></TD></TR><TR><TD><FONT SIZE=-1><BLOCKQUOTE>
On 2001-08-02 09:56:17, AntnyMD wrote:
Have you tried to click on 3:2 pulldown in the Advanced tab? I've never used it; I'm guessing.
</BLOCKQUOTE></FONT></TD></TR><TR><TD><HR size=1 color=black></TD></TR></TABLE>

yup, see my first post...

[AntnyMD]

no, no, no

Your first post said you used 3:2 pulldown on MPEG-2 video, which you would have selected on the first tab in TMPGEnc settings.

If you encode the source MPEG-1, which has the framerate of 23.976, the 3:2 option on the first tab is not available. However, on the Advanced tab, there is always present a 3:2 pulldown option (look way down the list). I wondered if you ever used *that* one.

[hitechjunkie]

yes, yes, yes

<TABLE BORDER=0 ALIGN=CENTER WIDTH=85%><TR><TD><font size=-1>Quote:</font><HR size=1 color=black></TD></TR><TR><TD><FONT SIZE=-1><BLOCKQUOTE>
i tried encoding the 23.97fps mpeg-1 directly to 29.97fps by using the 3:2 filter in tmpgenc, but not only does it reconstruct frames but fields as well which ultimately introduced really bad interlacing artifacts in the progressive-only mpeg-1. it be nice if i could enable the 3:2 filter but disable the fields portion of it. </BLOCKQUOTE></FONT></TD></TR><TR><TD><HR size=1 color=black></TD></TR></TABLE>

[hitechjunkie]

<TABLE BORDER=0 ALIGN=CENTER WIDTH=85%><TR><TD><font size=-1>Quote:</font><HR size=1 color=black></TD></TR><TR><TD><FONT SIZE=-1><BLOCKQUOTE>
On 2001-08-02 09:56:17, AntnyMD wrote:
What is that recompression to MPEG-2 then recompression back to MPEG-1 doing to the quality of your video?
</BLOCKQUOTE></FONT></TD></TR><TR><TD><HR size=1 color=black></TD></TR></TABLE>

not much, really. take a look at the effects and conclusion of recompressing mpegs...

[hitechjunkie]

well i just completed my first conversion and it did not work. what appears to be happening is the mpeg-2 is created at 23.97fps with the 3:2 pulldown flag. this allows the mpeg-2 to play smoothly and totally in synch with the audio in my ATI software DVD player. this tells me the mpeg-2 is "good".

- if i load the mpeg-2 into tmpgenc directly and encode to mpeg-1, 29.97fps, all it does is change the framerate but without the extra frames, so it plays the 23.97 fps movie at 29.97fps, which causes the video to go too fast and completely ahead/out of synch with the audio. it's like it's not detecting the 3:2 pulldown flag.

- if i load the mpeg-2 into dvd2avi (no problem scrolling through the entire movie), save the project and load the d2v file in tmpgenc, the frames are all out of whack, distorted, green blocks, etc.

- if i load the mpeg-2 into flaskmpeg (no problem using the player throughout the entire movie), and try encoding to a 29.97fps mpeg-1 using Ligos, the mpeg-1 does not playback smoothly.


i am encoding the original mpeg-1 to mpeg-2 using the DVD template with just the rez modified. we'll see...

[AntnyMD]

When you load the re-encoded MPEG-2 into DVD2Avi, are you telling it to FORCE FILM? Don't do that if you are.

[hitechjunkie]

it worked!! what i did was

1 - load the 23.97fps mpeg-1 in TMPGEnc
2 - load the NTSC DVD template
3 - load unlock template
4 - change output rez to match input
5 - unchecked "3:2 pulldown on playback" and "Interlace"
6 - used CQ_VBR 0-9000 instead of CQ

i then encoded to a really nice looking/playing 29.97fps mpeg-2 (actually better looking than the lower bitrate mpeg-1, if possible).

i then read the mpeg-2 with DVD2AVI, saved the project, loaded it into TMPGEnc, and reencoded to a 29.97fps VBR mpeg-1. this provided a low bitrate (0-1050) VBR mpeg-1 XVCD which plays smoothly and flawlessly on my standalones, totally eliminating the stuttering experienced previously.