Conference Paper

Face Detection in Low-Resolution Color Images.

DOI: 10.1007/978-3-642-13772-3_46 Conference: Image Analysis and Recognition, 7th International Conference, ICIAR 2010, Póvoa de Varzim, Portugal, June 21-23, 2010. Proceedings, Part I
Source: DBLP

ABSTRACT Most face detection methods require high or medium resolution face images to attain satisfactory results. However, in many
surveillance applications, where there is a need to image wide fields of view, faces cover just a few pixels, which makes
their detection difficult. Despite its importance, little work has been aimed at providing reliable detection at these low
resolutions. In this work, we study the relationship between resolution and the automatic face detection rate with the Modified
Census Transform, one of the most successful algorithms for face detection presented to date, and propose a new Color Census
Transform that provides significantly better results than the original when applied to low-resolution color images.

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    • "However their higher resolutions can still be considered as very low. For instance, [32] showed improved detection rate from 6 × 6 to 24 × 24 resolution using Modified Census Transform (MCT) and Boosting on colour Fig. 10: Expression classifiers over Sobel detected faces using the 25% bound. When considering the results of Figure 11, the Sobel expression classifiers shows best performance. "
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