Framerate conversion
I guess the only reason to change the framerate is that you downloaded the source.
The following little guide should help you to cange the framerate from 23.976 to 25 fps or vice versa.
If you have a 29.97 fps or an odd framerate like 15 or 20 fps, I dont know a good solution, then you have
to do a real framerate conversion, so you will end with jerky playback. Well, some people do not even notice
that, but since a real framerate conversion is done by duplicating / deleting frames, the final MPEG wont
play smooth.
Start with decompressing the audio. Load the .avi or .mpg into VirtualDub, select file > save WAV
(PCM uncompressed).
1. Video
1a. Video conversion with TMPGEnc.
Load the source file as video source, load a template, go to the advanced tab. Check "do not framerate
conversion"
Set whatever you want else, select "video only" and start conversion.
1b. Frameserve with Avisynth
Code: |
Avisource("c:..dir..filename.avi")#PALsource
#BilinearResize(448,254,1,0,638,272)
#AddBorders(16,113,16,113)
AssumeFPS(23.976)
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Code: |
Avisource("c:..dir..filename.avi")#NTSCsource
#BilinearResize(448,306,1,0,638,272)
#AddBorders(16,135,16,135)
AssumeFPS(25)
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If the source is MPEG-1 use DirectShowSource instead of AviSource.
If the source is MPEG-2, create a DVD2AVI project and get the mpeg2dec plugin for Avisynth.
Code: |
LoadPlugin("c:..dir..mpeg2dec.dll")
mpeg2source("c:..dir..filename.d2v")
#BilinearResize(448,254,1,0,638,272)
#AddBorders(16,113,16,113)
AssumeFPS(23.976)
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Load the .avs as video source into your favorite MPEG encoder.
1c. Frameserve with VirtualDub
Open the source file in VirtualDub. If the source is MPEG-2,
create a dvd2avi project and convert
it with VFAPIconv. Then open the fake *vfapi.avi in VirtualDub.
Select video > framerate.., change the framerate
Add all filters you like and start the frameserver. Load the *.vdr resp. the *vdr.avi as video source
into your favorite MPEG encoder.
2a.Audio with BeSweet
Start the BeSweet GUI. Set the path to BeSweet.exe[1], input[2]and output[3] file.
Select the output format[4], check downsampling if necessary[5].
At the OTA section change framerate[6] from 960 to 1001 (23.976 to 25 fps). BeSweet does not support 1001 to 960
(25 to 23.976 fps) yet. You may use Cool Edit.
Go to the SSRC tab. Select options.
At the 2Lame select the output options.
Back to the BeSweet tab press WAV to MP2.
3. Multiplex
2b.Audio with CoolEdit
Open the WAV audio in CoolEdit, select transform > time / pitch > stretch
You see the origininal length of the in seconds, here 559.096 = 9:19.096 x 25fps= 13977 frames
13977 frames / 23.976 fps = 582.96 = 9:42.96. Compare the time to the time of video file.
Press OK. It takes a couple of monutes.
Save as WindowsPCM (*.wav). Continue with downsampling (CoolEdit or BeSweet[ssrc]) and audio
conversion, e.g. with BeSweet.
3. Multiplex View
user comments or post your own comments/issues about this guide
here.
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