The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. Vol. XXXVII. Part B4. Beijing 2008 
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In this study, Landsat TM image date 1992/10/21 and JERS1- 
SAR image date 1992/10/27 of Hanoi, Vietnam are used. 
JERS1-SAR image was resampled to 30m resolution to 
correspond with Landsat ETM image. It also is applied 
GAMMA 3X3 FILTER to reduce noises. And it was corrected 
about geometry by orthogonal geometric correction before 
using. Following figure is JERS1-SAR image after these 
processing: 
By this way, we have perfect data for experimenting the remove 
cloud method including: cloud image to test the cloud defining 
method, to test the interpolation method and we also have 
original data (under cloud data - before overlay cloud) to 
compare with interpolated result for validation. Following is 
Landsat-TM image after overlaying cloud 
Figure 3. Landsat TM image date 1992/10/21 after overlaying 
cloud 
Figure 1. JERS1-SAR image 30m resolution after GAMMA 3. METHODOLOGY 
3X3 FILTER and Orthogonal Geometric Correction 
Outline of methodology is illustrated in the following figure: 
In the Landsat TM image, there is no cloud. Cloud was gotten 
from another Landsat TM image and overlay to Landsat TM 
image date 1992/10/21 as following figures: Methodology 
ALOS-AVNIR2 Image 
Define Cloud 
ALPS PALSAR data 
ÄfflSÄCoiKctipn 
JÄeSSdl 
Get Shadow 
Tmm 
reduce* 
INTERPOLATION 
Figure 4. Flow chart of methodology 
3.1 Defining Cloud 
Reflectance of cloud is always high from visual wave to near 
infrared wave. So, values of cloud will be high in all 4 bands of 
ALOS-AVNIR data. With thick cloud, we are very easy to 
define it by TRRI index. This index is defined by the following 
formula: 
TRRI 
J ^ max A 
* 100 
Figure 2. Landsat TM image date 1992/10/21 (up) and Landsat 
TM image used to get cloud (down)