Converting 23.9 to 29.97

[kitty]

I have a NTSC film divx (of a Southpark episode) that I'd like to convert to NTSC 29.97 so I can use Studio to splice up to add to a project

I believe if it was telecined it would get the proper frame rate (29.97) without audio problems. But Virtualdub only has Inverse Telecine - changed my 23.97 to 19 fps. If you do a straight framerate conversion the audio goes out (as Vdub states quite clearly in the conversion dialog)

Help

Da Kitty

[Bluez]

export the audio stream, load the audio stream in an audio editor, change the length of the audio stream (time stretch), fire up vdub, select the video stream, select the adjusted wav file as audio source, force the framerate to what you want... done

[kinneera]

While that method will work, I figured it was worth commenting - playing the same number of frames at 29.97 fps will actually result in about a 20% speedup on playback, and necessitate a shortening, not stretching of the audio. Both adjustments are likely to be at least mildly irritating, even to the casual viewer.

[Ryu_hoshi]

man trying to edit the audio to make it longer and stuff will give you a headache, cuz its hard to get it just perfect. Just use videdit and goto convert frame rate, and set it to 29.97

[kitty]

VidEdit as in the Microsoft video editing program?

[MITSUI_1]

Since South Park is animated material and, ahem, not all that "smooth" anyway, just

1. LOAD up that clip in TMPGenc.

2. Set the output framerate to 29.97 fps

and 3. Either save as uncompressed AVI or frameserve to VDUB and save as an AVI.

TMPGenc will ADD one extra "duplicate" frame to every group of 4 resulting in a proper frame rate. (You can tell by the fact that the number of frames outputted will be 20% higher than input).

You're audio SHOULD still sync up perfectly.

If you're really anal, take the raw AVI you save with TMPGnc using this method and open it with avisynth using decomb.dll with and only the "Decimate (mode=1,threshold=50)" command in the script. This will cause avisynth to go in and find all those "dupe" frames and change them from exact duplicates to an interpolated blend of the dupe and the following frame. Some people say this makes it look smoother.

[Bluez]

mitsui_1, you just gave me an idea... i don't know if it exists, but... how would the following work?

1. every file is a number of frames, which are played back at a certain speed

2. to change the framerate, a program should generate a new file frame by frame

3. each outputted frame should be an interpolation between two original frames, which frames and how much of each frame shows up in the output would depend on the frame position...

4. the above might be unclear, let me add an example:

a. input 10 fps
b. output 30 fps
c. output frame 1 would be input frame 1
d. output frame 2 would be 2/3 of input frame 1 and 1/3 of input frame 2
e. output frame 3 would be 1/3 of input frame 1 and 2/3 of input frame 2
f. output frame 4 would be input frame 2

5. the above mechanism would allow fluid conversions from any framerate to any other framerate without creating audio artifacts...

does such a program exist?

[Fred©]

Well, I have downloaded a software that claims to change frame rate, but havent tried yet... I dont know why nobody has talked about it until now, but it seems to be a "serious" software...

It is VideoMach 2.6.0.

You will find it at www.gromada.com

Please, if you try its framerate conversion, please email-me ok? My computer is too slow to make a real test (with no garantee)...

Fred©

[Bluez]

lots of software can change framerate, i am a registered vmach user (but they ask you to pay for every minor update, grrr) i bought the program to handle mavicam mpegs that sometimes aren't handled by other applications

however, all software thus far changes framerates by adding / subtracting frames, what we need is something that interpolates (yet there is some hope, i'm talking to a developer who might just be able to make our life a lot easier... someday...)

[Fred©]

Bluez,

this week I finally tried VideoMach to change the framerate of a captured file from 29,97 fps to 23,96fps... the idea was to have a smaller file... instead, the source was 0,98 GB and the new file was 1,00 GB...
I did not understand what changed in output file... all I know is that I will not spend my time (18 hours of convertion) with NTSC / NTSCFilm convertion...

Fred©

[Bluez]

hey, fred, i can imagine

fortunately, i run more than one machine at home, i have a 24/7 machine acting as internet gateway / edonkey platform / tmpgenc batch processor, so i just feed the beast new files, and once in a while check for crashes or if something has been completed

you're right about not waiting though... on to videomach, the result would depend on the encoder / codec, but yes, files *can* increase in size...

did you use exactly the same settings as the original file?

[Fred©]

Bluez,

I dont remember that I have setup the compressor/codec at the output file... all I noticed was that resolution and bitrate was the same, but, while the framerate of the video was correct (23,97), the interleave of the audio was 23 fps.. no way to change it to 23,97... only 23 or 24 options were acceptable...

Now I am more interested at your friend... the developer... when some new software become released, please, let me know, ok?

Fred©

[kitty]

For me TMPGenc worked with good audio sync. Score another win for the champ of all encoders. Thanks MITSUI!

[ViperXT]

What you want is a little option called "3:2 Pulldown". It is availible in TMPGEnc in two ways. You can select it in the setup and if is an mpeg2 output file you can select "3:2 pulldown on playback", this means it encodes 23.97fps but it is converted in realtime to 29.97 by the player.

[kitty]

You misunderstood what I wanted. I have a 23 fps video. I need it in 29.97 so I can cut it up & splice it into a short I am making. Having the player conver is not what I need at all.

Most video editors want source material in the same format to edit.