Circuits Syst Signal Process (2009) 28: 913–923 915
Fig. 1 Parallel camera geometry model
2 Vector Estimation and Weighted Disparity Interpolation
2.1 Loop Constraint in Motion and Disparity Field
We establish an accurate parallel camera geometry model by jointly calibrating cam-
eras, because parallel camera geometry is the most appropriate simulation model of
the human visual system and it ensures that a vertical component of a disparity vector
is zero, which greatly simplifies the calculation of disparity fields [6]. The scene is
captured by cameras C
1
, C
2
, C
3
and C
4
separately, as shown in Fig. 1(a). Suppose
that a point in the scene moves from M to M
. Viewpoint images captured by cameras
at different times (t and t +k)areshowninFig.1(b). For the same time, the disparity
vector is defined as a vector connecting the corresponding points between adjacent
viewpoint images (e.g. X
1
−X
2
). For the same view, the motion vector is defined as
a vector connecting the corresponding points between successive images in time (e.g.
X
1
−X
1
). B is the baseline distance, that is, the distance between adjacent cameras
which are considered to be equal in our geometry model.
In general, the disparity vectors between viewpoint F 1 and F 2 at time t and t +k
should be:
d
F 1F 2
x
= X
1
−X
2
(1)
d
F 1F 2
x
= X
1
−X
2
(2)