latexdiff - diff latex files

http://www.pppl.gov/~hammett/comp/tex/latexdiff.html

http://packages.ubuntu.com/lucid/latexdiff

$ sudo apt-get install latexdiff

~/bin/latexdiff old.tex new.tex > diff.tex

Git commands

# get version from 10 commits ago 

git show HEAD~10:chapter1_de.tex > chapter1_de_v1.tex
git diff HEAD HEAD@{10} chapter1_de.tex > diff-head-head10.txt