[Gdal-dev] compose seperate band satellite images.

[Frank Warmerdam]

Zhonghai Wang wrote:
> Hi there,
>  
> I've got three satellite images B0, B1 and B2 from the Internet, where:
>  
> B0 for the BLUE band, Landsat band 1
> B1 for the GREEN band, Landsat band 2
> B2 for the RED band, Landsat band 3
>  
> and I am trying to compose them together in one GeoTIFF image using 
> openEV, here I've got some strange symptoms:
>  
> if I set the stack order as B0 B1 B2 (from top to bottom), I get a image 
> color; if I set the stack order as B2 B1 B0 (from top to bottom), I get 
> another image color. This is a little bit weird for me, since each image 
> has its own band color, and these colors are the real color, i.e RGB, if 
> I compose these three image together, the composed image should have the 
> nature color, and this should be unique.
>  
> frankly say, I am not very good at remote sensing things, your thoughts 
> will be very helpful for me.

Zhonghai,

OpenEV and GDAL don't know which band ought to be red, green or blue
except based on the order you compose them.  So you should put the
band you want to be red first (B2), then green (B1) then blue (B0).

Best regards,
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