30fps to 25fps without jitter....PLEASE HELP!

[Doppelgofer]

does anybody out there know how to convert 30fps to PAL standard, 25fps and make it completley jitter free? please help

[flaninacupboard]

you can't. you're chucking away 5 frames a second, and obviously you can see that. Does your TV not support NTSC? a lot of TV's in PAL territories do.

[adam]

Its possible as long as the source originated as film. If so, then the frames that were added to it to make it 29.97fps were done so in a specific pattern, and an inverse telecine filter can remove them and reconstruct the original 24fps progressive whole frames. From there, its a simple speed up to PAL.

If this is a DVD, than shame on you for not reading any of the guides. NTSC DVDs are almost always stored as 23.976fps. Just load it in dvdavi and enable forced film and make your d2v file to frameserve the movie as 23.976fps, and from there just speed it up by %4.

If this is some other source than try loading it in TMPGenc and double clicking on the source range filter in the advanced tab. Scroll through it frame by frame and if you see 2 interlaced frames for every 3 progressive ones, than your source has undergone at typical 2:3 telecine and can easily be inverse telecined. TMPGEnc has an IVTC filter and there are many others accessible through virtual dub or avisynth.

If you are going to use TMPGenc exclusively, then set output FPS to 25, set your PAL res of course, check the "do not framerate conversion" filter on the advanced tab, and double click on the inverse telecine filter on the advanced tab and select 24fps and hit auto-setting.

Like flaninacupboard said though, unless your hardware is from the stone age, it shouldn't have any problem playing the NTSC footage as is.

[Xesdeeni]

If you are starting with 30 progressive frames per second and going to interlaced PAL, you can get reduced "jitter" by converting to 50 fields per second. It won't go away, but it won't be quite as bad as throwing away 1 out of every 6 frames.

Xesdeeni

[Doppelgofer]

well the thing is is that im only amateur wen it comes to things like this and i work with a simple video camera and i capture video into my computer at 30fps and i work in a 30fps orientated enviroment....as soon as i export and render down to 25fps, it looks crap.....

the thing is aswell is that the thing i'm after convertin down contains a lot of subliminals and flashes of stuff so i really don't want to lose em

can anyone just give me a step by step guide cos im not findin any on this website.......oh and as much as i appreciate your reply before adam, i'm not too technical wen it comes to things like this

[DivXExpert]

Avisynth has a command called ConvertFPS, and it works very well. It works similar to a set top frame rate converter box, sortof a frame interpolation, by blending frames. The only problem is that it kills compression rates. But its either that, or jerky motion.

[DivXExpert]

Pay no attention to the "toast" link, it was just a mess up in the auto linking the the forum.

[Xesdeeni]

well the thing is is that im only amateur wen it comes to things like this and i work with a simple video camera and i capture video into my computer at 30fps and i work in a 30fps orientated enviroment

You can refer to http://www.geocities.com/xesdeeni2001/StandardsConversion in general (it needs a bit of an update), but without spending big $$$, you cannot be jitter free. You can get reasonable quality with a script like this:

AVISource("NTSC.avi")
SeparateFields()
Weave()
SmoothDeinterlace(doublerate=true)
ConvertFPS(50) # or ChangeFPS(50)
LanczosResize(720,576)
SeparateFields()
SelectEvery(4,0,3) # or SelectEvery(4,1,2)

Some notes:

1. To check the input polarity, comment out (use #) all the lines after SmoothDeinterlace() and view the results with VirtualDub. Step through a few dozen frames where there is motion and be sure that the motion is correct when moving forward frame-by-frame.
2. ConvertFPS() interpolates between frames. The results using this will be similar to the least expensive standards conversion hardware. That is, you will see "jutter," which is caused by parts from multiple source frames being visible in the same destination frame. ChangeFPS() just replicates, or in this case decimates (removes) frames. Jutter does not occur, but there will be a "jump" in smoothly moving video (unlikely with hand-held video). This also might be a problem if you have single frame flashes.
3. The output of this script is interlaced, so you will see lines if you view it with VirtualDub...THIS IS CORRECT.
4. The last line depends on your destination field polarity. In general, SelectEvery(4,0,3) is good for DV (e.g. saving back to AVI), while SelectEvery(4,1,2) is good for DVD (i.e. feeding directly to an MPEG-2 encoder). You must actually encode some test footage with low and high motion to ensure that the field polarity is correct. If the destination video jumps back and forth as it moves, use the other SelectEvery() setting.

Xesdeeni

[flaninacupboard]

Doppelgofer,
Are you sure you need to convert it?
99% of new PAL televisions, and a lot of older ones are actually multi system so can play back the 30fps NTSC file no problems. Even if yours doesn't i have NEVER seen a PAL DVD player that can't transcode 30fps to 25fps on playback. The results from that are similar if not better than using avisynth.

[Doppelgofer]

cheers everyone.....flaninacupboard, the reason i want to make it into pal is say i want to give the dvd to someone whos telly doesn't support ntsc and has to watch it in black and white with a stretched picture.....thats the only reason i want to convert it

[flaninacupboard]

yeah, but like i said, i have NEVER seen a PAL dvd player that can't transcode NTSC to PAL. tell them to look in the setup menu, and where "TV Type" is set to Auto, tell them to set it to "PAL" or "PAL Only" as some say.

It will now only output PAL, and the NTSC material will get transcoded.