Saudi Journal of Engineering and Technology (SJEAT)
Volume-3 | Issue-07 | 437-445
Original Research Article
Face-priority Auto Focusing with Color Correction
Yuan-Kai Wang, Chin-Fa Wang, Hong-Yu Chen
Published : July 30, 2018
Abstract
Automatic focusing is very important to high-quality image acquisition for
camera system. This paper proposes a new automatic focusing method using skin-color
face detection to automatically determine focusing area. In order to overcome the
influence of color temperature on the face detection method, we propose a new color
correction method by learning a color temperature curve with statistical methods. The
color temperature curve is a concise representation of the inverse relation between light
sources in the logarithmic color space. The method compensates color shifts of images
by locating a set of compensation gains from the trained color temperature regression
curve. A comparative setup of experiments is built to verify the effectiveness of the
proposed method. Controlled experimental factors include light source, object distance
and initial lens position. Modulation transfer function of images is applied to objectively
evaluate the image quality before and after the new automatic focusing method.
Experimental results show our method has high success rate of face localization, and
effectively achieves automatic focusing.