Change Frame Rate

[bozitaai]

Dear all,

I used two methods to change frame rate of VOB file (from 23.976 fps to 29.97 fps)

Method 1
1. Open the VOB file using DVD2AVI
2. Goto "Video" menu and select "Field", then press on the "None"
3. Goto "File" menu and select "Save Project"
4. d2v file and AVS file are generated

The frames rate increases to 29.97 fps and the new frames are created by TELECINE method.

Method 2
1. Open the VOB file using DVD2AVI
2. Goto "Video" menu and select "Field", then press on the "Forced FILM"
3. Goto "File" menu and select "Save Project"
4. d2v file and AVS file are generated
5. Insert "ChangeFPS(29.97)" into AVS file

The frames rate increases to 29.97 fps and the filter just simply duplicate the frames.

The output quality of these two methods is not good. Any methods can convert the frame rate from 23.976 fps to 29.97 fps with good quality?

Thank you very much

Bozitaai

[Guest]

What is your definition of "with good quality"?

[bozitaai]

Method 1
Some strips appear on the video.

Method 2
The video isn't smooth.

Any methods can convert the frame rate from 23.976 fps to 29.97 fps without such problem?

Thank you.

[Guest]

Those "strips" are interlacing. If your target display device is a TV, then they won't be a problem. What is your target device and why do you need the conversion?

If you are looking for conversion of 23.976 progressive to 29.97 progressive without blending or duplication then you will need motion-compensated frame interpolation, such as that provided by MotionPerfect. But be warned, it is far from perfect. For practical purposes, it is impossible.

[pieroxy]

As neuron2 said, if your display device is a TV, interlacing is what you need. If your display device is not a TV, then you probably don't need to change the framerate.

[ppera2]

Only reply what this thread deserves is:

http://forum.doom9.org/showthread.php?s=&threadid=34696
Sticky!

[bozitaai]

Where can download the Telecide and Decimate Filters for AVISynth?

Thank you

[Wilbert]

:search:

http://www.avisynth.org/warpenterprises/ (decomb)

[ukb008]

DVDPatcher can also do it, along with a host of other file-attributes.

Regards.

[ppera2]

Originally posted by neuron2
...
If you are looking for conversion of 23.976 progressive to 29.97 progressive without blending or duplication then you will need motion-compensated frame interpolation, such as that provided by MotionPerfect. But be warned, it is far from perfect. For practical purposes, it is impossible.

Right, 'MotionPerfect' is far from perfect. But I saw some development there. I would be careful with word 'impossible', although. Remember, what Lord Kelvin said about aviation :)

My idea is that motion-compensated frame interpolation should be performed in (mpg) encoder, because it already performs intensive motion analysis. Of course it's still not enough, but may be some way, which will at least good for not doing same thing twice.

I know, that separation of objects is main problem here, plus we need to 'calculate' 3D shapes by 2D pictures (frames).
If you have some arguments about that 'impossible', I will glad read them .

[Guest]

I said "For practical purposes..." which implies with technology readily available to the poster right now. It seems you actually agree, because you didn't offer him a practical solution.

[ppera2]

Originally posted by neuron2
I said "For practical purposes..." which implies with technology readily available to the poster right now. It seems you actually agree, becuase you didn't offer him a practical solution.

"For practical purposes, it is impossible" - I don't see here that it is about right now. Must say, that you are here often very sparse on words, and people not understand what you want to say (in best intentions).
I will certainly not offer 'him' any solution, because this forum is full with threads about framerate conversions. Myself spent lot of time by experimenting with different methodes.
I think that people should try what is best for them, because it is very subjective. See discussions between Xeesdeni and Scharfy's Brain.

[Guest]

I did not say frame rate conversion was impossible. Please read my posts more carefully.

[ppera2]

Originally posted by neuron2
I did not say frame rate conversion was impossible. Please read my posts more carefully.

Actually, I don't know what you wanted to say. What means word 'impossible' to you at all?

I don't care for all this much, to continue this 'conversation' when one ask other to be more carefully, but replies on well explained post in 3 seconds.

Or, I can say to paraphrase: write your posts more carefully :)

[DigitAl56K]

Originally posted by bozitaai
Dear all,

I used two methods to change frame rate of VOB file (from 23.976 fps to 29.97 fps)

Method 1
1. Open the VOB file using DVD2AVI
2. Goto "Video" menu and select "Field", then press on the "None"
3. Goto "File" menu and select "Save Project"
4. d2v file and AVS file are generated

The frames rate increases to 29.97 fps and the new frames are created by TELECINE method.


No they aren't. The "new frames" were there already.

The 23.976 version was created when the field operation was "Force FILM".

If the VOB file didn't have 29.97fps to begin with you could not create 29.97fps with this method. DVD2AVI does not telecine.


Method 2
1. Open the VOB file using DVD2AVI
2. Goto "Video" menu and select "Field", then press on the "Forced FILM"
3. Goto "File" menu and select "Save Project"
4. d2v file and AVS file are generated
5. Insert "ChangeFPS(29.97)" into AVS file

The frames rate increases to 29.97 fps and the filter just simply duplicate the frames.


This time you are actually creating frames, but what you have actually done is 29.97fps telecined, ivtc to 23.976, generate frames.

[ppera2]

Originally posted by DigitAl56K
No they aren't. The "new frames" were there already.

The 23.976 version was created when the field operation was "Force FILM".

If the VOB file didn't have 29.97fps to begin with you could not create 29.97fps with this method. DVD2AVI does not telecine.

This time you are actually creating frames, but what you have actually done is 29.97fps telecined, ivtc to 23.976, generate frames.

Creating frames? New frames? Total misunderstood...
ChangeFPS is not telecine. And it not creates frames, but duplicates or drops. DVD2AVI telecines when source is FILM and Force Film is unchecked. It's made according to Riff flags in Mpeg2 video. Please read about things. With this way you just make additional confusion here.

[mpucoder]

Sounds like semantics. Some would say that duplicating a frame creates a frame, but I believe ppera2 uses "create" to mean making a blended frame from the frames on either side.
Telecine is a process of transferring film to video and has nothing to do with framerate conversion, although the word has come to mean pulldown (possibly due to the fact that for NTSC both a transfer and pulldown are done at the same time). The word itself is a made-up word combining "television" and "cinema".
And mpeg-2 by way of the rff flag can do pulldown without any additional source frames.

[ukb008]

What did Lord Kelvin say about aviation?

Just changing fps between 29.97 and 23.97 will induce abnormal motion. To compensate frames have to be added or taken out. These frames must come from the elements already present. In that sense they aren't new. But if they weren't there before and are present now, then what are they if not new?

It is purely semantics. But do get on, gentlemen.

Regards.

[jggimi]

"Heavier than air flying machines are impossible."

[ukb008]

In this context I am reminded of an ad by a Japanese electronics giant (Panasonic? Toshiba? Mitsubishi? I forgot):

Technically, anything is possible.

Regards.

[ppera2]

Originally posted by ukb008

Just changing fps between 29.97 and 23.97 will induce abnormal motion. To compensate frames have to be added or taken out. These frames must come from the elements already present. In that sense they aren't new. But if they weren't there before and are present now, then what are they if not new?

It is purely semantics. But do get on, gentlemen.

Regards.

OK. We can say that there are new frames, however it's not usual terminology. Much better is talking about duplicating, because it says little more.
But main problem with DigitAl56K's post was that his post is confused:

Original post:
"5. Insert "ChangeFPS(29.97)" into AVS file

The frames rate increases to 29.97 fps and the filter just simply duplicate the frames."

'Explanation' :
"This time you are actually creating frames, but what you have actually done is 29.97fps telecined, ivtc to 23.976, generate frames."

What he said is bad formulated, and wrong - ChangeFPS is not same as telecine, which is little complexer, and Avisynth has command for it, something like 3:2 pulldown, but I don't have here manual to see exact command.