Image Processing Reference
In-Depth Information
Fig. 9.2 (continued)
color and depth map image sequences are considered to obtain
luminance
and
contrast
measures of the metric.
Luminance
and
contrast
information calculated
at the sender side only occupies a few bytes per frame. This justifies that we could
name the proposed method as a
Near NR
metric rather than a
RR
method. The
structural similarity (SSIM) metric in [
31
] is modified to measure the effect of
luminance
,
contrast
, and
structural
information in the proposed method. Equations
(
9.1
), (
9.2
), (
9.3
), (
9.4
), and (
9.5
) show how the SSIM calculation is performed.
Structural similarity (SSIM) index between signal
x
and
y
:
α
:
ʲ
:
ʳ
SSIM x
ðÞ
¼
;
y
lx
ðÞ
;
y
cx
ðÞ
;
y
sx
ðÞ
;
y
ð
:
Þ
½
½
½
9
1
where
SSIM
(
x
,
y
) represents the similarity map,
0 and l(
x
,
y
),
c
(
x
,
y
), and
s
(
x
,
y
) represent
luminance
,
contrast
, and
structural
comparisons
respectively. l(
x
,
y
),
c
(
x
,
y
), and
s
(
x
,
y
) components are given by (
9.2
), (
9.3
), and
(
9.4
) respectively.
α>
0,
ʲ>
0, and
ʳ >
