ffmpegConvert video to h264

ffmpeg -i input.mp4 -c:v libx264 -preset ultrafast -crf 17 output.mkvctrl + cyoutubegithub

`-i input.mp4` input video to convert	`-c:v libx264` select video codec, h264 lib in this case
`-preset ultrafast` encode faster but produce larger file (use `-preset veryslow` for better compression)	`-crf 17` sets quality to the very good one (use `-crf 0` for lossless encoding)
`output.mkv` resulting h264 video file