When uploading videos to youtube thay can get huge and uploads might take a while. FFMPEG can reduce size of the files pretty heavily. I had a screencast of 190 MB that ffmpeg converted to 17 MB, which saved me a ton of time during upload considering upload bandwidth that my ISP gives is far lower than download bandwidth.
Below is the simple no-nosense command that you can use.
ffmpeg -i RawInput.mkv encoded-output.mp4
You can also have filters during encoding. To reduce white noise you could use following.
ffmpeg -i RawInput.mkv -af “afftdn=nt=w, afftdn=nt=w” encoded-output.mp4
-af is for audio filters.
To use video filters -vf
There are many other filters available if you need them. check them here.
Hope this saves you some space and time.