In this paper, a novel feature named Adaptive Contour
Feature (ACF) is proposed for human detection and segmentation.
This feature consists of a chain of a number of
granules in Oriented Granular Space (OGS) that is learnt
via the AdaBoost algorithm. Three operations are defined
on the OGS to mine object contour feature and feature cooccurrences
automatically. A heuristic learning algorithm
is proposed to generate an ACF that at the same time define
a weak classifier for human detection or segmentation. Experiments
on two open datasets show that the ACF outperform
several well-known existing features due to its stronger
discriminative power rooted in the nature of its flexibility
and adaptability to describe an object contour element.