Adding a transparent object on image

Abstract

Nowadays, image manipulation, which is related to matting and compositing process, is commonly used. Processed object may vary, however matters may arise when the object is transparent. Not many research has been conducted about the issue due to the difficulties in extracting transparency value and object refraction. In this research an application to execute matting process of a transparent object and compositing it into a new image is developed.Matting process will be executed using Grabcut method, followed by calculation of transparency value of an object using alpha matting. The transparency value is then used in compositing an object with a new background, while refraction will be executed using refraction calculation of ray tracing. Adding a transparent object into new image (new background) process, first user should determine the eye’s position and distant between new image and transparent object. Then, assume the additional transparent object as a screen to trace rays from eye. Each ray will be bent and hit the new image. The color of new image will add into the transparent object area.Experiments result showed that extracted transparency value was affected by lighting, refraction of the old background, which unknown and object's refraction index. Refraction result looks natural compared with the actual condition. Moreover, eye position can be configured by the user to obtain results as desired.