git/Documentation/config/filter.txt

filter.<driver>.clean::
	The command which is used to convert the content of a worktree
	file to a blob upon checkin.  See linkgit:gitattributes[5] for
	details.

filter.<driver>.smudge::
	The command which is used to convert the content of a blob
	object to a worktree file upon checkout.  See
	linkgit:gitattributes[5] for details.