8mm Forum: AVISynth script for lowering FPS

This is topic AVISynth script for lowering FPS in forum 8mm Forum at 8mm Forum.

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Posted by Bill Vendasi (Member # 4815) on November 21, 2015, 09:03 AM:

Hi all,

I just started working with AVISynth and I'm using this script to
lower the frame rate of some very old 8mm films.

Import("C:\Program Files\Avisynth\plugins\sRestore.avs")
AVISource("COMPLETE.avi")
ConvertToYV12(interlaced=true)
QTGMC(Preset="faster")
Srestore(Frate=19.98)
AssumeFPS(12)
Crop(8,0,-8,0)
LanczosResize(640,480)

I had to run the projector very fast to avoid flicker, which worked ok but the result was almost Keystone Cops speed. After trying 20, 18, 16, & 14 FPS, the above script brought the speed to what looks normal to me.

But as you probably know, 12 FPS looks kind of jerky and duplicate frames play a big role in this effort as well.

If anyone has any suggestions or better scripts to do this I'd love to try them.

I wanted to post a small example clip but I'm not sure how to do it here.

Thanks,
Bill

Posted by Bill Vendasi (Member # 4815) on November 23, 2015, 07:11 AM:

and maybe somebody could post a good recipe for Chicken Florentine.

Posted by Lee Mannering (Member # 728) on November 23, 2015, 07:32 AM:

You will need
2 spoons olive oil
200g spinach
1 garlic clove
126g mozzarella cheese
720ml tomato pasta sauce
2 teaspoons sugar
half cup Basil leaves
Quarter cup plain flour
Roasted small potatoes and some Broccoli
Don't forget 4 chicken breasts.

Alternatively you can plug in a Super 8mm cine projector and really enjoy watching some films, the better option!
[Cool]

Posted by Janice Glesser (Member # 2758) on November 23, 2015, 01:26 PM:

Hi Bill... A lot depends on what the original fps the film was shot at and what fps your camera captured. If these were home movies most likely it was shot at 18fps. Your camcorder should be set to 60 or 30fps and the projector speed around 20fps. This should reduce or eliminate any flicker.

If you just want to slow the captured image down you can do this directly in Virtual Dub without removing any duplicate frames. However, I use a "No-Dups" AVISYNTH script that uses DGbob & FDecimate plugins to remove duplicate frames and set the FPS. You'll have to determine your own parameters.

LoadPlugin("DGbob.dll")
LoadPlugin("FDecimate.dll")

DirectShowSource("your filname here.avi")
ConvertToYUY2()

# Convert to fields and shifting every other field by half a line:
DGBob(order=0,thresh=12)

# Remove duplicate frames:
# In the last line, you need to fine tune the resulting frame rate (currently 16.0). Fractional numbers are allowed.
# In the ideal case, you should see no duplicate frames and no skipped frames.
FDecimate(rate=16.6667, threshold=3)

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