International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B3. Istanbul 2004 
adopted the 4:1:1 sampling. In Type RGB the source image 
was separated into three color component (Red, Green and 
Blue) images, and each color component image was 
compressed and decompressed respectively. Evaluation of 
quality of the reconstructed image was executed after 
combining three decompressed color component images. 
We used LuraWave SmartCompress 3.0 by Algo Vision 
LuraTech GmbH for JPEG 2000 compression. We prepared 
JPEG 2000 compressed image data of the same size of JPEG 
compressed image data of Type S444. 
As for Blocks C2 and H3, only Type S444 was investigated. 
3.3 Measures of Image Quality of Reconstructed Images 
The following numerical image quality measures were 
examined. 
(A) Gray level features 
a) PSNRs of RGB (Red, Green, Blue) components 
(B) Color features 
a) PSNRs of HSV (Hue, Saturation, Value) components 
Each component of HSV color space has 256 levels (8 
bits). 
(C) Texture features 
a) Standard deviations of RGB components 
b) Grey level difference vector (GLDV) measures: 
  
  
  
  
  
  
  
  
150 
S411 
e —9-- Sá|l / 
8 100 —— Rod / 
© — Blue / {it Blue 
e # 1 Green 
E. 50 / 4. JAA Red 
= pra J 
ue etd I i À 
IE RR x pem 
0 eins T | 
100 80 60 40 20 0 
1JG quality setting 
Figure 5. Compression ratio vs. JG quality setting 
(IJG quality setting: 100 - 0) 
  
  
   
   
   
   
  
  
  
  
  
20 , S411 
H3 
os — SH ] l a 
e 15 77 RGB oes 
S m. CÓ E. yt D o 
= eus jou e Do 
2 P L^ € CE 
e p rr ed RGB 
o ; n ane 
o s] v crat 
2 d tem 
(7 Wu pert 
X 
o ! 
100 90 80 70 60 50 
[JG quality setting 
Figure 6. Compression ratio vs. IJG quality setting 
(IJG quality setting: 100 - 50) 
Contrast, Angular second moment, Entropy, Mean 
c) Mean spatial frequency of Fourier power spectrum 
An image of finer texture features has higher values of 
texture measures except GLDV Angular second moment 
and a lower value of GLDV Angular second moment. 
3.4 Results 
Since the effect of changing compression ratio on PSNR of each 
  
  
  
  
  
  
  
  
  
44 —— S444T ] 
E 
= 40 
© 
= 
6 
rx 
Z - 36 
N 
a 
32 
Compression ratio 
Figure 7. PSNR of Hue vs. compression ratio 
  
  
  
   
   
   
   
    
   
   
   
   
  
  
  
  
  
  
50 
+ RGB 
2 erc Si 
= —— RGD 
eg 45 m 
8 memes 
a — M3 
S 
N 
© 
cz 40 
Z 
un 
e 
35 
0 4 8 12 16 
Compression ratio 
Figure 8. PSNR of Saturation vs. compression ratio 
  
       
   
   
   
   
  
  
  
  
56 
a 32 -—-- $411 
© : 
= -—— RGB 
S 48 ei 
3 
> —— H3 
© 
> 44 
Zz 
N 
a 
40 
36 | 
0 4 8 12 16 
Compression ratio 
Figure 9. PSNR of Value vs. compression ratio 
650 
In 
Cc 
R 
Standard deviation 
GI.DV Contrast