PHOTOMANIPULATION, THE EASY WAY

Abstract:

The typical smartphone user has many thousands of photos in their personal collection.
Photo acquisition is effortless, and the next challenge is in devising methods to easily edit
such large collections. Specifically, we need manipulation algorithms that are powerful
enough for experts, yet simple for novices to master.
We identified three key directions to empower novice users with expert-level editing
capabilities while maintaining an overall simplicity in the process. Those directions are
(1) better selection masks, (2) high-level goal-centric algorithms and (3) domain specific
algorithms. In this thesis we give examples from each category.
Given a photo, a novice user will typically either not edit it at all, or apply a simple
global operation such as exposure correction. In contrast, a professional photo editor
might perform local edits, specifying a selection mask to limit the operation to specific
photo regions, or combining regions from several photos into a single composition. To
ease selection mask creation we present a new patch embedding technique that allows for
single-click selection masks.
Novices often think in terms of goals (e.g. improve lighting, de-clutter photo) and less
in technical terms such as color spaces and image layers. One example of a high-level
goal is the removal of distracting elements from photos. The task is motivated by the
way professional photographers operate. They carefully frame the scene and might move
objects around in order to stage the perfect photo. We define “photo distractors” as the
elements that, if removed, would improve the photo. Using a simple slider interaction we
allow users to automatically remove such distractors from photos.
It is at times useful to tailor solutions to specific photo types. As an example we show
that, specifically for human heads, simple controls can induce sophisticated edits. Given a
single portrait photo as input, we can change the pose of the head and the camera distance.
This allows users to correct the “selfie effect”, i.e. big noses and small ears or to transform
distant photos into selfies.
iii
We conclude by discussing how each of these directions can be further explored to
enable better image editing tools for novices.