Digital Signal Processing Reference
In-Depth Information
Fig. 2.5
Test sequences: (
a
)
Mosaic; (
b
) Ball; (
c
) Akiyo;
(
d
) News (The desired color
objects are marked with
triangles)
Fig. 2.6
Segmented images
obtained by the PCT method
using threshold and logical
operation: (
a
) Mosaic;
(
b
) Ball; (
c
) Akiyo; (
d
)News
sequence
suggested in [
17
] and applying some logical operations, we can obtain four seg-
mented images as shown in Fig.
2.6
. Although the main parts of the desired object
are extracted, noise cannot be easily de-correlated from signal.
The test sequences are shown in Fig.
2.5
embedded with different characteristics.
The scenes of these four sequences are quite different. Akiyo sequence has a blue
static TV screen on her background and with some background color similar to
Akiyo's face. Carphone sequence has large head movement and fast scene changes
outside the car window. Due to fast head movement, the lightness changes occur
on his face very quickly. This lightness effect is usually hard to overcome by other
