Show git-diff-image output also on 'git show' and 'git log -p'?

[ottok]

Is this diff tool designed to work only when specifically running git diff, or everywhere git diffs are displayed, such as in git log and git show?

I have only gotten it working when running explicitly git diff. Hence I was wondering did I setup it incorrectly, or is it not being used got git log -p and gitk output at all.