AbstractRevision control is a vital component of digital project management, and
has been widely deployed for text files. Binary files, on the other
hand, have received relatively less attention. This could be
inconvenient for graphics applications, which can use a significant
amount of binary data, such as images, videos, meshes, and animations.
Existing strategies such as storing whole files for individual revisions
or simple binary deltas could consume significant storage and obscure
vital semantic information. We present a nonlinear revision control
system for images, designed with the common digital editing and
sketching workflows in mind. We use DAG (directed acyclic graph) as the
core structure, with DAG nodes representing editing operations and DAG
edges the spatial, temporal and semantic relationships between
operations. We visualize the DAG in an intuitive and user friendly
revision graph, RevG, which serves not only meaningful display of the
revision history but also common revision control operations such as
review, replay, diff, addition, branching, merging, and conflict
resolving. Beyond revision control, our system also facilitates artistic
creation processes in common image editing and digital painting
workflows. We have built a prototype system upon GIMP, an open source
image editor, and demonstrate the effectiveness of method through user
study as well as comparisons with alternative revision control systems. |