An extended set of Haar-like features for rapid object detection

TLDR

Viola et al. introduced a rapid object detection scheme using a boosted cascade of simple feature classifiers. This study introduces rotated Haar-like features and a post‑optimization procedure for boosted cascades. The method extends the Haar-like feature set with rotations and applies a post‑optimization step to the cascade.

Abstract

Recently Viola et al. [2001] have introduced a rapid object detection. scheme based on a boosted cascade of simple feature classifiers. In this paper we introduce a novel set of rotated Haar-like features. These novel features significantly enrich the simple features of Viola et al. and can also be calculated efficiently. With these new rotated features our sample face detector shows off on average a 10% lower false alarm rate at a given hit rate. We also present a novel post optimization procedure for a given boosted cascade improving on average the false alarm rate further by 12.5%.