Progressive 29.97fps to 23.976fps?

soujir0u · 24th September 2002, 11:38

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 · 24th September 2002, 11:43

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

soujir0u · 24th September 2002, 11:45

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 · 24th September 2002, 12:05

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) as he corrected a bug a short while ago.

WarpEnterprises · 24th September 2002, 12:31

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

hakko504 · 24th September 2002, 12:38

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

soujir0u · 24th September 2002, 12:55

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

soujir0u · 24th September 2002, 12:59

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

DJ Bobo · 24th September 2002, 13:05

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 · 24th September 2002, 13:27

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 · 24th September 2002, 13:40

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 · 24th September 2002, 23:42

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.

24th September 2002, 11:38	#1 \| Link
soujir0u Registered User Join Date: Oct 2001 Posts: 213	Progressive 29.97fps to 23.976fps? 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?

24th September 2002, 12:05	#4 \| Link
hakko504 Remember Rule One Join Date: Oct 2001 Location: SWEDEN Posts: 1,611	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) as he corrected a bug a short while ago. __________________ /hakko http://www.boardgamegeek.com

24th September 2002, 12:38	#6 \| Link
hakko504 Remember Rule One Join Date: Oct 2001 Location: SWEDEN Posts: 1,611	Warp is right, sorry, I mixed up those functions. __________________ /hakko http://www.boardgamegeek.com

24th September 2002, 11:43	#2 \| Link
WarpEnterprises C64 Join Date: Apr 2002 Location: Austria Posts: 830	If there are duplicate frames you can use Decimate() from Donald Grafts decomb package.

24th September 2002, 11:45	#3 \| Link
soujir0u Registered User Join Date: Oct 2001 Posts: 213	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.

24th September 2002, 12:31	#5 \| Link
WarpEnterprises C64 Join Date: Apr 2002 Location: Austria Posts: 830	The function which blends frames is ConvertFPS. ChangeFPS does a rather dumb decimation. (As far as I understood)

24th September 2002, 12:55	#7 \| Link
soujir0u Registered User Join Date: Oct 2001 Posts: 213	I tried ConvertFPS, but the resulting video looks like it was motion blurred. I'll try new Decomb...

24th September 2002, 12:59	#8 \| Link
soujir0u Registered User Join Date: Oct 2001 Posts: 213	Decomb, too jerky. I think I will just stick to 29.97 fps, but this video is too uncompressible!

24th September 2002, 13:05	#9 \| Link
DJ Bobo Encoding Dinosaur! Join Date: Oct 2001 Location: Europe Posts: 1,668	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!

24th September 2002, 13:27	#10 \| Link
soujir0u Registered User Join Date: Oct 2001 Posts: 213	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.

24th September 2002, 13:40	#11 \| Link
WarpEnterprises C64 Join Date: Apr 2002 Location: Austria Posts: 830	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.

24th September 2002, 23:42	#12 \| Link
soujir0u Registered User Join Date: Oct 2001 Posts: 213	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.