How to speed up the framerate ?

[Mounir]

I wanna slightly speed up the frame rate by about 3%, how could i do that ?

[thewebchat]

AssumeFPS(last.framerate*1.03)

[Mounir]

I see, what's the significance of this number "1.03" or maybe it's too complicate to explain ?

[neuron2]

0.03 x 100 = 3%

[Mounir]

Alright that's crystal clear.

If i wanted to have the audio sped up at the same time, i suppose something must be added , right ?

[shoopdabloop]

AssumeFPS(last.framerate*1.03,sync_audio=true)

Wouldn't you want to stick to a common framerate for encoding though?

[Mounir]

nah it's cool shoopdabloop i know why i do that

[Mounir]

I just tried with the sound and it's not synchronized with the video ! What did i miss ?

[JohannesL]

I just tried with the sound and it's not synchronized with the video ! What did i missed?

This:

AssumeFPS(last.framerate*1.03,sync_audio=true)

[Mounir]

Yeah i used that, but i know what went wrong anyway i have converted the sound in mp3 afterward and somehow that's what bring the de synchronization.

[scharfis_brain]

after speedup with audio syncronisation, the sample rate of the audio will be off standard.
you need to resample the audio back to its original rate eg.:

AssumeFPS(last.framerate*1.03,sync_audio=true)
Resampleaudio(48000)

[NerdWithNoLife]

This reminds me of a question I've had, and it seems to be the right thread. Does anyone have recommendations for speeding up the framerate a lot, for time lapse photography? I've done it before with SelectEvery, but what about interpolating for smoother motion?

Let's say I want to show an hour in 6 seconds, so that's 600x. Does anyone have a better idea than SelectEvery(600,0), then MFlow? Is it worth selecting extra frames so there are more data points for interpolation?

[Gavino]

Unless I'm missing something, interpolation only makes sense if you're slowing down the action (hence adding frames). If you're speeding it up by an integer factor, what is there to interpolate (assuming you keep the same display framerate)?

I suppose you could do
SelectEvery(300, 0)
AssumeFPS(2*frameRate)

[neuron2]

No need to recreate the in-between frames. You've already thrown them out! Just don't.

So the extreme case is just do an AssumeFPS() with a high frame rate.

The limiting case is how fast your display can run.

In-between case: SelectEvery() half of them and AssumeFPS() as required. Etc.

Hope I have been not too unclear. The point is that you have the frames you need, so no need to try to interpolate them.

[NerdWithNoLife]

That does make sense. However, after throwing out the frames I don't want, I still might have a desire to use MFlowBlur (without changing the framerate) to make it look less like stop motion.

But with my 60Hz monitor, and often a target of DVD, there's no reason for me to go beyond 60fps.

[shoopdabloop]

Perhaps

SelectEvery(300,0)
#high quality MAnalyse and MFlowBlur
SelectEvery(2,0)

would do the trick?

[2Bdecided]

That does make sense. However, after throwing out the frames I don't want, I still might have a desire to use MFlowBlur (without changing the framerate) to make it look less like stop motion.To do it convincingly, you'd need to do that before you throw frames away, not after.

However, you just need a temporal blur in this case (temporalsoften) - no need to use motion interpolation when you're throwing frames (and lots of them!) away.

Cheers,
David.