Silent Film (Framerate Question) Help

[johnmeyer]

Originally Posted by manono

And with respect to Sharc, the whole point to encoding it progressively and adding soft pulldown later on is to avoid the problems associated with hard pulldown. The bitrate savings are considerable, something like 40% for the same quality, as compared to encoding the interlacing.

This is an extremely important point.

I got my start encoding video twenty years ago when I wanted to take various music videos and put them on CD-ROM. I initially used the VCD encoders, but eventually "upgraded" to using SVCD and then XVCD.

What I found was, that at the really low bitrates those specs permitted, that if you encoded a music video from OTA, and if that video was shot on film (many were), I was getting absolutely horrible results than when I encoded videos that were shot as video.

I then read about IVTC, and when I used the TMPGEnc built-in inverse telecine, I suddenly got results that were spectacularly better than what I got at the same bitrate when I didn't remove the pulldown.

So, IMHO, IVTC is not optional; it is mandatory. Never encode video which contains pulldown.

[nfv]

Originally Posted by manono

Only if you like counting twice as much as is necessary. We've been through this before. Apply TFM to field match and then begin counting.

It's a pretty simple one, with a cycle of only 22 frames:

TFM(pp=0).TDecimate(Cycle=22,CycleR=6)

For which you get 21.796fps. You might not want to leave pp=0 for the whole thing, in case there are some quirks along the way. If for another DVD, it can be soft telecined using DGPulldown. Otherwise I'd leave the framerate alone.

I found some duplicate frames. With pp=0 and without on both scripts.

TFM(pp=0).TDecimate(Cycle=22,CycleR=6)

TFM().TDecimate(Cycle=11,CycleR=3)

Also, there is left over visible interlacing in sections.

[manono]

Originally Posted by nfv

Also, there is left over visible interlacing in sections.

Which is why I wrote in my first post:

Originally Posted by manono

You might not want to leave pp=0 for the whole thing, in case there are some quirks along the way.

Unless that wasn't with pp=0. Sometimes you have to tighten up the cthresh if there's some small amount of interlacing left from time to time. In addition, aliasing (jaggies) is sometimes mistaken for interlacing.

I found some duplicate frames. With pp=0 and without on both scripts.

All anyone had to go on was the sample you provided. If the cycle changes in other places, then provide another sample. Also, a duplicate frame here and there is way way better than missing frames as it's not normally noticed when played at full speed. Missing frames are much more noticeable.

[nfv]

Originally Posted by manono

Which is why I wrote in my first post:

Unless that wasn't with pp=0. Sometimes you have to tighten up the cthresh if there's some small amount of interlacing left from time to time. In addition, aliasing (jaggies) is sometimes mistaken for interlacing.

All anyone had to go on was the sample you provided. If the cycle changes in other places, then provide another sample. Also, a duplicate frame here and there is way way better than missing frames as it's not normally noticed when played at full speed. Missing frames are much more noticeable.

I sent you a PM with link to entire film. The movie is in the public domain but I've posted public domain clips before and had people get upset for some reason.

On this particular film what do you recommend I set the cthresh to? What would be the proper syntax be for the cthresh?

Yeah it could have been aliasing...Thanks!

[manono]

I'll pass. Good luck.

[nfv]

Originally Posted by manono

I'll pass. Good luck.

Thanks. What about my cthresh question?

[videoh]

You have to figure that out yourself by trying different values. The cthresh syntax is documented in the user manual.