50p to 25p framerate conversion

[cweb]

Hello
I need to convert from 50p (progressive) footage framerate to 25p...

What's a good present way of doing this in Avisynth (without desyncing audio of course)?

Should I use convertfps or is there a better way which I'm overlooking?

I was thinking perhaps this should work: AssumeScaledFPS(video,divisor=2)
thanks in advance

[Guest]

SelectEven()

[thewebchat]

Or SelectOdd() if you want to be a rebel.

[Guest]

Or SelectEvery(2,1) to be extra rebellious.

[cweb]

Thanks! I thought of that was being too obvious and I hadn't tested that yet. I tried it and it works....

[cweb]

One thing seems to have happened though with the SelectEven, the video seems to be too fast!
I would like to keep the normal speed of my camera recording.
I'm using the latest MT avisynth posted in another thread.

[cweb]

Hmm I think it was caused by my source.
My source is a camera video, an mts file which I convert to ts using tsMuxer. The latter by default uses vbr.
I access the ts file using directshowsource.
The speed was quite odd after going to 25fps...

I solved it by choosing the cbr option in tsMuxer, I created a cbr ts file instead, which seems to work well.
Thanks anyway.

[Gavino]

What do you mean 'too fast'?
SelectEven does not change the video duration.
It halves both the frame rate and the number of frames, so there is no change in playing time.

Probably all you are seeing is that motion is less smooth at 25fps than at 50fps.

Edit: Ok, just seen your later explanation.

[SeeMoreDigital]

cweb

Out of interest... Are you able to provide a sample of your 50fps source?