1. HW#4: Image Compositing
[Due: 12/5]
Composite the following images using the chroma-key technique (soft-keying) :
Foreground images: object1.ppm
Background image: bg.ppm
Hint:
Obtain the 2D color histogram of a selected area(to be eliminated. Eg. Blue background) on Cr, Cb plane (Y=0.3R+0.59G+0.11B, Cr=R-Y, Cb=B-Y)
Obtain the parametric description of the area to be eliminated on Cr, Cb plane
For each pixel, calculate the Cr, Cb value and decide if the pixel belongs to foreground or background or ambiguous area.
If (foreground) result foreground,
else if (background) result  background
else result  weighted_average(foreground, background)