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msjvenegas9 post(s)
#18-Nov-21 21:19


I have a 2-m digital elevation raster (image) that weights around 20 gb. While M9 has no problems on reading this image, I need to export the layer to another program that cannot handle the size.

Is there any process in which I can decrease the size of the image? I am OK to lose accuracy, a 5-10 m elevation should be fine, but I need it as a raster (line contours won't work).

I tried tracing the image to convert it to a vector, and then use the vector to raster method described in the manual, but maybe there is a better way.



364 post(s)
#18-Nov-21 22:08

One way is to check to see if you have it stored as a 32 or 64 bit value. If you could change the type to a float32 you will save some weight. If you are adjusting the pixel size it is done with a Reproject Component command. In the dialog for this there may be some checkboxes set to auto, the top one allows you to adjust the x & y dimension size for pixels. Try these two to reduce your image(DEM) size.


9,886 post(s)
#18-Nov-21 22:11

There is more than one way, but the easiest is to use Edit > Merge.

This is counter-intuitive, no doubt, but it works perfectly.


Example: Resize an Image using Merge

msjvenegas9 post(s)
#18-Nov-21 23:24

Thanks oeaulong and tjhb! I tried both methods and worked great!

I really like the option using merge, it's so simple!


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