Download, Extract, Convert videos

Download video with youtube-dl.exe

youtube-dl https://www.youtube.com/watch?v=S277aJyUehw

Converting video formats with ffmpeg.exe

ffmpeg -i input -c:v libx264 -crf 23 -preset medium -c:a aac -b:a 128k \
-movflags +faststart -vf scale=-2:720,format=yuv420p output.mp4

ffmpeg -i test.mp4 -codec:v libtheora -qscale:v 6 -codec:a libvorbis -qscale:a 6 test.ogv

Extract part of a video with ffmpeg

ffmpeg -ss 00:00:30 -i orginalfile -t 00:00:05 -vcodec copy -acodec copy newfile