linux cheat sheet

git

#rebase from upstream
#first add the upstream refer into .git/config
#[remote "upstream"]
git rebase upstream/master

#remove last commmit
git reset --hard HEAD^

pdf

#unite pdf
pdfunite 1.pdf 2.pdf destiny.pdf

#decrease pdf size
gs -sDEVICE=pdfwrite -dCompatibilityLevel=1.4 -dPDFSETTINGS=/printer -dNOPAUSE -dQUIET -dBATCH -sOutputFile=small.pdf big.pdf

timelapse

#cut mp3 so it does not finish after movie
mplayer -quiet tarantella.mp3 -ao pcm:fast:file=tarantella61.mp3 -endpos 0:61

#create movie adding mp3
mencoder mf://*.JPG -audiofile tarantella61.mp3 -vf crop=2040:2040:40:0 -mf fps=15:type=jpg -ovc lavc -lavcopts vcodec=msmpeg4v2:vbitrate=16000:keyint=15:mbd=2:trell -oac copy -o output.avi

#transcode to whatsapp
ffmpeg -i broken.mp4 -c:v libx264 -profile:v baseline -level 3.0 -pix_fmt yuv420p fixed.mp4

transcode

#transcode to panasonic 2012 tv
ffmpeg -i origin.mp4 -profile:v main -tune film tv.mp4