23.976fps to 29.97 fps conversion blues!

[Mannish Boy]

Hi guys.
Ok, so I have my .avi at a frame rate of 23.976fps, and I want to turn it into a DVD compliant MPEG2. Usually, I load the .avi into TMPGEnc, load the NTSC DVD profile, then go into settings and change Encode Mode to '3:2 pulldown when playback' and change the Frame Rate to '23.976 s (internally 29.97 fps)'. The resulting DVD is quite wwatchable, but the picture certainly isn't smooth.
Any and all advise on smartening up the smoothness of the DVD will be greatfully received!
Thanks in advance!

[dafreak]

is playback jerky?

[adam]

Well those are the correct settings to use. Only one thing comes to mind off the bat. Check the advanced tab and make sure that the 3:2 pulldown filter isn't checked. TMPGenc will analyze your source and attempt to set things up accordingly, and with a 23.976fps source, if you loaded the NTSC template then you would also need to enable the pulldown filter, so maybe its doing it for you. Since you are doing a soft telecine instead (good choice) then this filter must be disabled.

Has this happened with other 23.976fps sources? If it only happens on this one then the source may not have originated at 23.976fps progressive, in which case a telecine will be jerky. May the person who encoded that avi deinterlaced or something.

[johns0]

I had the same problem and the way i got it smooth was encode at 29.97 fps with no pulldown.

[Drakng]

John0.. I am also having the same problem. Jerky video especially when motion is involved.Now 23.976 is normally non-interlaced whereas 29.97 is interlaced. A question for you. Do you changed the tab non-interlaced to interlaced . Also your method would make redundant the 3:2 pulldown.
Won't there be any trade-off?

[adam]

johns0 is talking about doing a hard telecine to 29.97fps. Its a much lower quality way to encode NTSC. You've got 20% more frames to encode, so its effectively like lowering your bitrate by about 20%. Furthermore, as you mentioned, you now are encoding interlaced material instead of progressive material. Interlaced material is inherantly more difficult for an encoder to work with and also requires more bitrate to achieve the same level of quality. It would be in your best interest keep trying to get this encode to 23.976fps done properly. It is the preferred way to encode NTSC material. At playback, the result is the same, the dvd player will just do the telecine instead of the software encoder. But since all those redundant fields won't have to be physically stored, you get a substantial quality boost.

So I'll ask again. Is this an isolated issue or do all your ntscfilm sources do it? And are you ensuring that the 3:2 pulldown filter is disabled on the advanced tab?

You might want to try just setting TMPGenc to 23.976fps and non-interlaced. Then you can add the pulldown flags with pulldown.exe instead.

[Drakng]

It's not isolated It's kind of ramdon with different avi. The pulldown.exe in the advanced tab is not checked. I will give your last suggestion a try.By the way the jerkiness happened at the motion section.Still or little movement does not jerk. Strange isn't it?

[Drakng]

One more thing I heard that too much sharpening might caused the jerkiness. I do a fair bit of filtering. What do you think?

[adam]

If it varies from one source to the next then its most likely that some of these sources didn't originate as film. There's not much you can do about that. Converting to 29.97fps won't help any either.

I wouldn't think that any of the filters offered in TMPGenc could cause jerky motion, but you never know. Try a test encode of a problem scene with no filters and see.

[Drakng]

Will give a go at different settings and see what happens !!
Thanks