Progressive 29.97fps to 23.976fps?

[soujir0u]

Hi, is there a filter that can remove some frames from a progressive 29.97fps source (change into 23.976) without resulting in jerky video?

[WarpEnterprises]

If there are duplicate frames you can use Decimate() from Donald Grafts decomb package.

[soujir0u]

Sorry, I forgot to mentio0n. All the frames are different (true 29.97fps progressive), and there are no duplicate frames... I tried decimate(cycle=5) a while back (Decomb 3.8) but some of the scenes (panning, etc) was jerky.

[hakko504]

Well, some jerkiness is probably unavoidable if you insist on reducing framerate to 23.976fps. Still, I suggest that you try the latest version (4.0rc1) of Decomb as the decimate function has undergone some quite heavy changes in the last versions, and is quite likely to produce better results now than with your old 3.8 version.

If you don't mind blended frames the try the internal ChangeFPS() command. In that case make sure you have the latest version of AVIsynth from sh0dan (2.05+190902) (http://cultact-server.novi.dk/kpo/avisynth/avs_cvs.html) as he corrected a bug a short while ago.

[WarpEnterprises]

The function which blends frames is ConvertFPS.
ChangeFPS does a rather dumb decimation.
(As far as I understood)

[hakko504]

:stupid: Warp is right, sorry, I mixed up those functions.

[soujir0u]

I tried ConvertFPS, but the resulting video looks like it was motion blurred. I'll try new Decomb...

[soujir0u]

Decomb, too jerky. I think I will just stick to 29.97 fps, but this video is too uncompressible!

[DJ Bobo]

First, why would you convert to 23,976fps?! this is non-sense! your video is progressive 29,97fps so keep it as is, it's wonderful and super smooth! and NTSC encoding works perfectly with 29,97fps!

Now, if you want PAL video, you would like to convert to 25fps, that will be another thing. Don't know (yet) what convertfps may output, but this is the method I use:

loadplugin("...\decomb.dll")
separatefields()
selectevery(7,1,2,3,4,5,6)
weave()
fielddeinterlace()
assumefps(25)

You'll have to slow down the audio part a bit (102,756%)

EDIT:
If it's too hard to compress, then use a smaller resolution, it's as simple as this!

[soujir0u]

Hehe, actually I already encoded with 29.97fps at 640x352 resolution but it needs too much bitrate (>2000kbps). I'm just looking for ways to reduce the bitrate required (for good quality). Guess I will look at filters such as Convolution3D (TemporalSmoother didn't help much) or resize to 5xx horizontal.

[WarpEnterprises]

What's your source and to what do you encode?
640x352 is a strange resolution but >2000kbit sounds very much for progressive at that res.

[soujir0u]

I'm encoding a concert DVD that was in 4:3 aspect ratio, but has thick black bars on top and bottom. I guess it's hard to compress cos it's kinda noisy, the original source was not very high bitrate (3 hours at only 7.8GB with LPCM audio). Also, lots of smoke and stuff floating around. Thanks Bach, I'll try your suggestion later.