We study the problem of object classification when training
and test classes are disjoint, i.e. no training examples of
the target classes are available. This setup has hardly been
studied in computer vision research, but it is the rule rather
than the exception, because the world contains tens of thousands
of different object classes and for only a very few of
them image, collections have been formed and annotated
with suitable class labels.
In this paper, we tackle the problem by introducing
attribute-based classification. It performs object detection
based on a human-specified high-level description of the
target objects instead of training images. The description
consists of arbitrary semantic attributes, like shape, color
or even geographic information. Because such properties
transcend the specific learning task at hand, they can be
pre-learned, e.g. from image datasets unrelated to the current
task. Afterwards, new classes can be detected based
on their attribut...
Christoph H. Lampert, Hannes Nickisch, Stefan Harm