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Hi, i'm new in the world of FME and trying to learn the working of it. Mostly by using the help function, this website en offcourse Google. But some problems seems to be a bit difficult ;)

 

 

What i try to do is comparing 600+ ecw files to 1 ecw file that i can use, by importing, in another program. I have been trying different ways to get the job done but still didnt find a way to make this happen.

 

 

I hope to find some help on this site.

 

 

Thx J-P

 

 

Hi,

 

 

Welcome to the world of FME !

 

 

Can you explain what you mean by comparing rasters?

 

 Are you interested in the visual quality? the raster values? or something totally different?

Itay

 

 

 
Hi Itay,

 

 

I will try to explain it.

 

 

What i got are 600+ ECW files with parts/pieces of a (total) map. All this files together will show you a big map for example a region. I want to compare this 600+ files so i got the big map in only 1 ECW file. Is there a way to get this done by FME?

 

 

J-P
Hi J-P,

 

 

The SpatialFilter can be used to test if a raster overlaps with the region. Or if you need to clip a raster with the region, consider using the Clipper.

 

And then, if you want to mosaic those filtered (or clipped) rasters into a single raster, have a look at the RasterMosaicker.

 

Hope this helps.

 

 

Takashi
Hi J-P,

 

 

As suggested you can create a mosaic from all of your rasters to compare with the map.

 

However if you are interested only in knowing if the rasters " cover" the map area you can best extract the bouding box of each raster and dissolve them. 

 

The bouding box of the map can be then compared to the dissolved bounding box of the ecw rasters.

 

This is a less time consuming option than mosaicking all of the 600+ rasters, but it doesnt provide you with the option of a visual comparison between map and rasters mosaic.
Hi Itay & Takashi,

 

 

Thanks for giving me this options/advise. I managed to get all the ECW files in a overview and that was showing the map i needed. But i didnt manage to save it in 1 ECW file, after saving it was showing the 600+ ECW files again.

 

 

You are talking about mosiac and some other options, but i didnt manage to use this. I'm using the FME Workbench. Can i find this options here or do i need 2nd part software?

 

 

Is it possible to give me a visual view from the options you talking about?

 

 

J-P
Hi J-P,

 

 

Did you try the RasterMosaicker transformer? I think it should work to combine input rasters into a single raster by default.

 

If you haven't tried yet, try with a few sample rasters.

 

http://docs.safe.com/fme/html/FME_Transformers/Default.htm#Transformers/rastermosaicker.htm

 

 

Takashi
P.S. If you are not familiar with Workbench and transformers yet, I recommend you to skim this documentation first.

 

FME Getting Started Guide

 

http://docs.safe.com/fme/html/FME_GettingStarted/Default.htm

 

 

Takashi

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