Project3 – Single View Metrology
Picture: My dining table
Painting: The Engagement
of Maria by Raphael (Raffaello, 1504)
1. Follow Bob Collin¡¯s
write up to calculate vanishing points. As described in the write up, translating
image coordinate to the center of image (set (0, 0) is in the center of them
image), gives a better result.
2. Calculate homography
between image plane and reference plane. To do that, I set one point as origin
of reference coordinate (0, 0, 0), and give reference coordinate value to one
point on the reference plane (X, Y, 0). Using relationship between vanishing
points and a projection matrix, I can get a projection matrix. Therefore, one
point on the reference plane (except origin) has to have X, and Y value. In
some cases in which it is not possible to do that, I give reference coordinate
value to two points (X, 0, 0 and 0, Y, 0).
3.
Specifying a
reference height, compute reference coordinate values for all points in my
image. Sometimes it¡¯s difficult to find out corresponding points (X, Y, 0) on
the reference plane for out of plane points (X, Y, Z). In this case, I drew the
line between vanishing points and points on the reference plane.
Positive
point of my approach:
Using lines between vanishing points and points on the image, it is possible to
find out corresponding points on the reference plane for some ambiguous points.
Negative point of my approach: Depending on vanishing points so much, vanishing points have to be computed accurately