Combining Haar Feature and skin color based classifiers for face detection

Abstract

This paper presents a hybrid method for face detection in color images. The well known Haar feature-based face detector developed by Viola and Jones (VJ), that has been designed for gray-scale images is combined with a skin-color filter, which provides complementary information in color images. The image is first passed through a Haar-Feature based face detector, which is adjusted such that it is operating at a point on its ROC curve that has a low number of missed faces but a high number of false detections. Then, using the proposed skin color post-filtering method many of these false detections can be eliminated easily. We also use a color compensation algorithm to reduce the effects of lighting. Our experimental results on the Bao color face database show that the proposed method is superior to the original VJ algorithm and also to other skin color based pre-filtering methods in the literature in terms of precision.

Face Detection in Intelligent Ambiences with Colored Illumination

“…Strong out-of-plane-rotations that lead to occlusions of facial parts, like one eye, may cause the classifier to fail. Even so, the skin segmentation improves the detection performance with respect to [8,23]. The second most signifi- …”

“…Figure 6 evaluates the performance of the proposed method (Shades of Grey-based skin segmentation previous to the VJ detector) under challenging image quality, pose, and illumination conditions. For comparison, we also report the accuracies of other state of the art face detectors, namely the basic VJ algorithm [23] and Erdem et al's method [8], which refines the VJ results with subsequent Grey World-based skin segmentation. The proposed method seems to be more sensitive to pose rather than quality or illumination.…”

“…Finally, it should be stressed that the moment at which the skin segmentation filter is applied is crucial (Fig. 6a): applying VJ on detected skin regions yields better performance than using a post-VJ skin segmentation filter [8] to refine the results (in terms of FP).…”

“…As a result, these algorithms missed skin regions, and as such, yielded a lower detection rate than the basic VJ detector. A skin color detector was used in [8] after the Viola-Jones module, in order to filter the correct detections. In this way, the authors achieved a low false positive rate, but did not improve the detection rate.…”

A Fast and Accurate Face Tracking Scheme by using Depth Information in Addition to Texture Information

“…Many subsequent researches have referenced them [5][6][7][8][9][10]. [5,6], and [9] proposed new classifiers to apply to a color image, and [7] designed a classifier that included skin color and eye-mouth features, as well as Haar-like features. [8] focused on the asymmetric features, to make a classifier for them.…”