18 fps DVD?

[kinglerch]

I have a video source that was taken from a silent 8mm video, native 18 fps. TMPGEnc has many encoding modes for 15, 19.98, 23.976, etc but no 18 fps. If I use some other mode, the video will either run at the wrong speed or not be smooth.

Can I do some sort of pulldown method in order to have 18 fps in a DVD? What program or TMPGEnc settings can I use?

[DereX888]

since it is *silent* just set output for 25fps or 29.97fps, whatever format youre doing there.
Unless youre affraid your movie's silence will desync?

You can't have other than 23.976, 25 or 29.97 framerate on DVD-Video anyway.

[duhmez]

I suggest set the framerate to 23.976(29.970 internal) (An easy way to get his set is load the tem plate for dvd>film then unlock it and tweak the rest of your setitngs as you see fit.) This will give you 23.976 ramerate with pulldown applied. Itll make for beter compression. It will look jerky and not the gretest, but what ya gonna do with 18 fps source!

[lordsmurf]

I have a video source that was taken from a silent 8mm video, ?

So, you actually transferred the film yourself, one frame at a time?
Or was your source a VHS made from the silent flick?

[DereX888]

So, you actually transferred the film yourself, one frame at a time?
Or was your source a VHS made from the silent flick?

true
But assuming his file is 18fps for some reason - I still don't see any problem converting it to whatever he wants (PAL or NTSC). No 'wrong speed', no desync (since it is silent), why even bother to do pulldown if he choses NTSC - just go straight for 29.97 interlaced or progressive as he pleases.

[kinglerch]

Yes, it is 18 fps for a reason. The silent source is 18 fps. If I go to 29.97 fps, it will look jumpy because frames must be added (about 1 for every 3) in order to reach 29.97.

Is there no way to do this? Like TMPGEnc 18 fps (Internally 29.97) or 3:2:2 pulldown or something?

If not, is 18 fps standard for another video format, like VCD or SVCD?

[bugster]

If not, is 18 fps standard for another video format, like VCD or SVCD?

For DVD the framerate MUST be 29.97fps (NTSC) or 23.976fps with pulldown, or 25fps (PAL). The same is true of SVCD. VCD allows 23.97fps without pulldown (its done by the player).

No Video standards use 18fps that I know of.

[kinglerch]

No Video standards use 18fps that I know of.

Yes, but strangely TMPGEnc includes many other frame rates like 1, 4, 15, etc that are non-standard. Just no 18 fps for some reason...

[adam]

Well TMPGenc is just an mpeg encoder, its not confined to any hardware based standard.

The fact is that there isn't much you can do. Converting to even 25fps is probably too much of a speed change for smooth playback. Just increasing speed is out of the question, it will move way too fast. If you repeat frames it will be like watching a movie while having a seizure. 29.97fps (23.976fps will still be played back at 29.97fps) will be even worse.

My only suggestion is to try and use one of those extrapolation filters. It can take two sequential frames and extrapolate one in between. It essentially guesses at what that missing sample would have looked like.

Othere then that your best option would be to double each frame and then go through and select certain ones at a given interval. You'd have to experiment to find which interval worked best, but my guess is that its always going to look bad.

[junkmalle]

If your final viewing platform is interlaced NTSC television your best results will come from a 4:3:3 pulldown in software. Using single digits as frame numbers and pairs of digits to repesent the two fields in a frame, the resulting MPG file will look like:

11 11 22 23 33 44 44 55 56 66

I tried some experiments in TMPGENC but couldn't get it to generate that pulldown pattern. But I was able to do it in Ulead Media Studio Pro 7.

First I created an 18 fps, uncompressed, progressive AVI file by taking a 29.97 fps progressive file and changing the frame rate with AVIFRATE. AVIFRATE only changes the header so the resulting file had all the frames from the original but played more slowly. Each frame was displayed for 1/18 of a second rather than 1/30 of a second.

I tried using that file in MSP7 but I couldn't get it to create the desired 4:3:3 pulldown. So I converted the file to a 90 fps AVI. I verified that each frame from the original was repeated 5 times in the resulting file.

I then loaded this into MSP7, told it the file was interlaced and generated an interlaced, 29.97 fps, DVD compatible, MPEG 2 file. The final result had the desired 4:3:3 pulldown and played about as smoothly as you could expect from 18 fps source.

[kinglerch]

This is a great help So what you are saying is my 18 fps source should be converted to 90 fps using the crude 5x duplication method, as can be done in many types of software. Then send it to Ulead Media Studio as interlaced and ask it to make a 29.97 fps DVD MPEG-2, and it automatically creates the 4:3:3? Are there any other settings in Ulead, or does it basically do the rest?

Thanks!

[junkmalle]

Yes, that's exactly what I did. The only tricky part is that you have to use the "Media Source Options" to tell MSP7 that the 90 fps file is interlaced (even though it's not). Otherwise it seems to want to retain full frames in the output.

[kinglerch]

One last question. Is there a program that analyzes MPG files and tells you details about the frame rate, pulldown ratio, etc?

Thanks for your help.

[junkmalle]

MSP7 can tell you the frame size, frame rate, and bit depth, and bit rate. AviCodec can tell you many of those things too but the version I have is sometimes erroneous. I don't know any program that can tell you the pulldown pattern automatically.

I used VirtualDubMod to examine individual frames of my 4:3:3 pulldown MPEG file. Since it allows you to step through the frames one by one I just counted the fields and frames.

[kinglerch]

You rule 8)

[kinglerch]

I sent the 90 fps video to Procoder since I am more used to that program. It did an excellent job and came out with a very smooth running 4:3:3. However, it looks to me like the fields run:

CA AA AB BB CC CA... instead of AA AA BB BC CC...

I tried changing the interlacing mode (Lower/Upper field first) but I couldn't get the second pattern. It's not a big deal and I don't think it changes the play very much, just something curious. Do you know which pattern you got from MSP7?

[junkmalle]

MSP7 gave me the second pattern: AA AA BB BC CC...

[lordsmurf]

I would have tried to double is to 36fps and then run a pulldown to make it 29.97. Not sure how that would have worked, but that would be my first thought and direction.

[chicola]

Have a look at www.100fps.com

Maybe you can improve something.

BTW, it has some nice examples.

[junkmalle]

CA AA AB BB CC CA... instead of AA AA BB BC CC...

I have an idea: trim a frame or two or three off the start of your 90 fps file!

[kinglerch]

Will try it, thanks.

[FOO]

There is always Avisynth. You can do just about anything with it.
30 to 18 is a 5:3 ratio. Need 5 frames for each 3 original

Separate fields
select every(  6, 0 , 1 , 0 ,3 , 2, 3 , 2 , 5 , 4 , 5 )
weave

will do this:
A A B B C
A B B C C

You could just dupe frames - AABCC
dunno which would be worse