I have clipped a raster to exact polygon outline using image analysis (ArcMap 10). The resulting temporary clip layer is exactly how I want it to be. However, when I export/save the temporary clip layer it is no longer clipped exactly to the clipping polygon. Can anyone suggest why this might be and how to work around?
Another way to clip a raster by polygon is to use the Clip tool located under
ArcToolbox → Data Management Tools → Raster → Raster Processing tools as follows:
- Select Input Raster
- Select Output Extent (the polygon shapefile)
Use Input Features for Clipping Geometry (optional)
- Save the out clipped raster data
Please make sure that both raster and polygon data have the same spatial reference system. I used geographic (WGS84) in the above example for both raster and vector polygon shapefile.
After running the tool, here is the output result:
Since your issue is related to coarse pixels as in this question: Saving a clipped image analysis raster that cannot be clipped to the boundary of your study area, try to use Resample tool before using the clip tool to resample the cell size into smaller cells. The Resample tool is located under
ArcToolbox → Data Management Tools → Raster → Raster Processing tools