<title>Online elimination of reflected images to generate high-quality images</title>

We often see scenes where an object's image is reflected on window glass and overlaps with a image of another object behind the glass. This paper proposes on-line methods for eliminating images reflected specularly on a smooth surface such as glass and plastic. Our methods are based on the optical property that light reflected on glass is polarized, while light transmitted through glass is less polarized. It is possible to eliminate reflected light with a polarizing filter. The polarization direction, however, changes even for planar glass and is not easily determined without information about the position and orientation of the glass and objects relative to the camera. Our method uses a series of images obtained by rotating a polarizing filter placed in front of a camera. Reflected images are removed by selecting just minimum image intensity among a series of images for each pixel. We propose two methods for estimating minimum image; one is min- max method and the other parameter estimation method. We conducted experiments with real images and compared the performances of the two methods. As a result, we could generate high quality image without reflected images at semi- video rate of 15 frames per second.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.