git-big-picture is a visualization tool for Git repositories. You can think of it as a filter that removes uninteresting commits from a DAG modelling a Git repository and thereby exposes the big picture: for example the hierarchy of tags and branches. git-big-picture supports convenience output options and can filter different classes of commits. It uses the Graphviz utility to render images that are pleasing to the eye.
https://github.com/esc/git-big-picture