git-change-commit-author

#!/bin/sh

git filter-branch --env-filter '

an="$GIT_AUTHOR_NAME"
am="$GIT_AUTHOR_EMAIL"
cn="$GIT_COMMITTER_NAME"
cm="$GIT_COMMITTER_EMAIL"

if [ "$GIT_COMMITTER_EMAIL" = "your@email.to.match" ]
then
    cn="Your New Committer Name"
    cm="Your New Committer Email"
fi
if [ "$GIT_AUTHOR_EMAIL" = "summers@Thunk5" ]
then
    an="Summers Pittman"
    am="supittma@redhat.com"
fi

export GIT_AUTHOR_NAME="$an"
export GIT_AUTHOR_EMAIL="$am"
export GIT_COMMITTER_NAME="$cn"
export GIT_COMMITTER_EMAIL="$cm"
' master..HEAD