With that scenario it is probably likely that you'll end up with a large resulting file unless you do some tweaking.

 

 

A couple of things to consider... the FeatureType on your Workbench canvas does have a "Compress by Percentage" parameter that you can experiment with. Open the properties and click on the 'Format Parameters' tab.

 

 

You might consider resampling your combined image if perhaps you don't need quite the resolution of your origin many images using the RasterResampler, this may reduce the file size but also the image detail when zoomed in.

 

 

You might want to look at coercing the Raster interpretation to limit or alter the Band allocation, take a look at the RasterInterpretationCoercer.

 

 

You might be interested in just a portion of the combined image so consider clipping out just what you need into the target image using the Clipper.

 

 

If those options don't work for you and you'd like to at least reduce the number of individual tiles from 40 to less, then consider using the RasterMosaicker followed by the RasterTiler to chop your image into a few larger tiles.

 

 

Hope that gives you some avenues for investigation.

 

 

Some links:

 

http://fmepedia.safe.com/articles/Samples_and_Demos/Understanding-Raster-Images

 

 

http://fmepedia.safe.com/articles/Samples_and_Demos/Raster-Mosaicking-Scenario

 

 

http://fmepedia.safe.com/articles/How_To/Tips-for-mosaicking-large-raster-datasets

 

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Hi Brian!

 

 

Also, remember that ECW stores the files in a fixed numbers of rows and colums. So if your area covers a road from for instance north-east to south-west it will be as large as the bounding box. A good test would be to run all the raster files through the BoundingBoxAccumulator and forward this to the inspector. ECW will save pixels also outside your areas if they are within this bounding box.

 

 

Instead of using ECW I would consider writing to a large BigTiff with JPEG-compression (although havent tried this with FME) yet, with proper tiling and compression-ratio.

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