How to Clip Rasters in ArcMap
You might be surprised to hear this… But there are two ways to clip rasters in ArcMap.
1. The classic technique is the raster clip tool in Data Management of ArcToolbox. This has been around for awhile.
2. The ArcGIS 10 Image Analysis Toolbar brings a way to clip rasters as well. The main advantage of the Image Analysis Toolbar is that you can visualize the end-result before you export it.
Sounds neat? Let’s take a look at both techniques to clip rasters in ArcMap.
Raster Clipping Techniques
1. Clip ( Data Management > Raster > Raster Processing > Clip )
2. Raster Clip (Image Analysis Toolbar)
In this example, we clip “Shaded Relief” (raster) to the state of Wyoming (polygon) using both clipping techniques.
Example 1: ArcToolbox Clip Raster Tool
Step 1: Select Clip Tool in ArcToolbox
In ArcToolbox ( Data Management > Raster > Raster Processing > Clip ), double-click the clip tool.
Step 2: Fill in fields
Input Raster (required) is the raster you want to clip. We want to clip the “Shaded Relief” raster.
Output Extent (optional) is the polygon boundary you want to clip to. You can select specific records in the polygon dataset and it will only clip this boundary. In our case, we would select the polygon of Wyoming before dragging and dropping it in the field. If you have coordinates instead of a polygon extent, type the maximum and minimum X and Y values.Use Input Feature for Clipping Geometry (optional) checkbox clip rasters to a polygon boundary. We want to clip to the state of Wyoming so insert a checkmark in the checkbox. Output Raster Dataset is the name of the output (clipped raster). Add an extension for the output (.TIF, .IMG, .JPG, etc.) NoData Value (optional) means all the pixels with the specified value will be set to NoData in the output raster dataset. This can be changed if you enter a value in this field.
Step 3: Run tool
Run the “clip” tool by clicking OK. The output raster will be clipped to the polygon extent.
Example 2: Clip Raster (Image Analysis Toolbar)
Step 1: Enable Image Analysis Toolbar
Enable the Image Analysis Toolbar ( Windows > Image Analysis ). The image analysis window will be displayed in ArcMap.
Step 2: Select Raster to Clip
In the image analysis toolbar, select the raster that you want to clip. Make sure checkbox is selected. Also, highlight the raster as well. If you don’t highlight the raster in the image analysis toolbar, the clip button will be greyed out.
Step 3: Select Polygon Boundary to Clip To
Select the record of the polygon that you want to clip the raster to.
Step 4: Click Clip Icon
Click the “clip” button in the image analysis toolbar. This will create a temporary raster. You can view the temporary clipped raster for an idea of how it will look when exported. All you have to do now is save this clipped raster.
Step 5: Export Raster
In the Image Analysis Toolbar, highlight the new clipped raster that has been created. Save the new clipped image by clicking the export button.
Choose the location and name of the file that you want to save. You can also change the cell size and the format of the clipped raster. Click save.
Why clip rasters?
Just think about each and every hour you’ve spent processing, analyzing and manipulating raster data.
Image resolution is becoming sharper meaning a requirement to work with larger raster file sizes. LiDAR data is a beast to work with. This puts the crunch on you and your processor. Wouldn’t it be nice to cut processing time down?
The good news is that you can save time when working with raster data.
How? Clip rasters to shapefiles (your area of interest). When you clip rasters, you generate workable subsets of data. We limit analysis to only the area of interest.
ArcGIS 10: Using Imagery Video