Graphics Reference
In-Depth Information
G
0
G
1
G
2
G
3
G
4
L
4
L
3
L
2
L
1
L
0
Figure 3.4.
The top row illustrates the Gaussian pyramid of an image
I
G
0
, generated by
filtering with the matrix in Equation (
3.3
) and downsampling by 2 at each step. Each image is
a smaller, blurrier version of its predecessor. The bottom row illustrates the Laplacian pyramid
for the image
I
, generated by successive differencing of the images in the top row according to
Equation (
3.4
). Each Laplacian image contains the edges at successively coarser scales.
=
where
indicates the images have been upsampled and interpolated to the original
image resolution before summing them.
To compose a source image
S
onto a target image
T
using Burt and Adelson's
approach, we first compute the Laplacian pyramids
L
S
and
L
T
for both images. We
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