How can I use ffmpeg to reduce output file frame rate from 50fps to 25fps?
#1
Now that we can only get 1280x720 downloads at 50fps I wondered if it might be possible to convert to 25fps to ease storage requirements. I ran a file through Handbrake and it seems to have done the trick. Can any ffmpeg expert tell me the command to do the same thing?
#2
Try:
Code:
ffmpeg -i <inputfile> -r 25 <outputfile>

As described in:
https://ffmpeg.org/ffmpeg.html#Description
#3
Thanks, easy when you know how :) I just tried it on a 5 minute clip and it reduced the size from 171 MB to 57 MB, more than I would expect from just dropping every other frame. The bitrate went from 4368kbps to 1353 kbps.
I'll try adding it to a get_iplayer command now.
#4
You may want to adjust encoding parameters to suit. Start here:

https://trac.ffmpeg.org/wiki/Encode/H.264


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