  This paper proposes an automatic image correction method for portrait
photographs, which promotes consistency of facial skin color by suppressing
skin color changes due to background colors. In portrait photographs, skin
color is often distorted due to the lighting environment (e.g., light reflected
from a colored background wall and over-exposure by a camera strobe), and if
the photo is artificially combined with another background color, this color
change is emphasized, resulting in an unnatural synthesized result. In our
framework, after roughly extracting the face region and rectifying the skin
color distribution in a color space, we perform color and brightness correction
around the face in the original image to achieve a proper color balance of the
facial image, which is not affected by luminance and background colors. Unlike
conventional algorithms for color correction, our final result is attained by a
color correction process with a guide image. In particular, our guided image
filtering for the color correction does not require a perfectly-aligned guide
image required in the original guide image filtering method proposed by He et
al. Experimental results show that our method generates more natural results
than conventional methods on not only headshot photographs but also natural
scene photographs. We also show automatic yearbook style photo generation as an
another application.
