144 145 
  
   
  
  
  
  
  
  
  
  
  
Percentage 
of pixels 
op === 
Sor 
30 | RECONSTRUCTION 
ACCURACY = 1 GREY TONE 
UNIT 
70 © 
(a) 
60 + 
| 
I 
| sor | 
40 | | 
| : NO ERROR 
ts/pixel | | | 
s IN ; Quantization 
| ] | 2 3 | 3 Step 
: : (LANDSAT 3) 
3.71 5/0 3.2 b/p 2.7 5/2 
poem T : (METEOSAT, IR) (b 
| 4.0 b/p 3.5 b/p 2.5 b/p ef 
| T T (NIMBUS 7) 
| | 3.5 b/p DE .. 1.7 n/p 
m Y (METEOSAT, VIS) 
2.7 b/p 2.0 b/p 1.3 b/p Average no. of bits 
per pixel (b/p) 
Figure 4 - Coding Performance versus tolerated Peak Error 
  
S. 
  
| | | | | | 
| DS Quant. | | | | | 
| Stap qQ | 0.3 | 1.7 | 3.4 | 6.8 | 
| Data | | | | | 
| J | | | | 
| | | | | ; | 
| LANDSAT 3 | 14020) | 3(3) | 5940) | 19 114) | 
| METEOSAT IR. | 1 (2 1 213) à 50) à 12 114) | 
| NIMBUS 7 R10) 4 20) ^|. 840) as FAY 1 
I METEOSAT Vis 3 14023) 3 390) 01 .50)] 4 91M) | 
| | | | | | 
  
Fig. 5 - Measured peak reconstruction error (grey tone unit levels) 
(N.B. : In brackets: value derived from the theoretical expression).