Demo of one computer vision application for the film postproduction: Mokey

Martin Urban

Imagineer Software Ltd. & CMP

Separating a selected object from a image sequence requires Chroma-key techniques or manual frame by frame re-working. Mokey is a user interactive software tool based on motion segmentation designed to make it easier. Mokey process consists of the following three main stages:

1. tracking of the roughly selected object (see Fig. 1) throughout the whole sequence and estimation of the illumination changes

2. automatic re-building of the previously hidden background areas - generating a clean background sequence (the foreground object removed), see Fig. 2

3. separeting the foreground object with the colour correction of mixed pixels on the object contours - generating a sequence of the separeted object (rgb+transparency) , see Fig. 3


Fig. 1. Rough selection of the background (defined with a Green boundary) and the foreground objects (defined with a Red boundary)


Fig. 2. Foreground object removed and background replaced


Fig. 3. Separated foreground element and the generated Matte