Edit thematic and classified pixels

Available with Image Analyst license.

You can use Pixel Editor to edit thematic and classified data. It contains tools to reclassify your data in the Edit group, as well as Operations that can be applied to the data. Reclassification of thematic data is useful when you only need to correct the incorrectly classified pixels, instead of having to reclassify the entire dataset.

The Capture group contains the Copy Region and Replace Region tools. These tools copy or replace pixels from the same dataset or from a different dataset in the map. If using another dataset within the map, use the Source Layer drop-down list to set the correct map layer to use; this layer must have the same bit depth as the raster being edited. The target layer is always the raster dataset that you are editing.

To interactively reclassify your data, first choose the field from the Current Class to reclassify. Next choose the New Class field to reclassify the original class data into the new class data. Then delineate a region to reclassify, and use the Reclassify drop-down menu to choose which tool you want to use:

• Reclassify Pixel —Point to the pixel you want to reassign, and click the map display. You need to be zoomed in to the pixel level to use this tool accurately.
• Reclassify Object —Use the circle tool to choose a group of contiguous pixels in which to reclassify. The center of the circle will determine the current class to reclassify, and the object will contain all contiguous pixels that are within the circle to be reclassified into the new class.
• Reclassify Region —Create a polygon to delineate the region in which to reclassify your pixels.

Note:

In order to choose Current Class or New Class, your attribute table must contain a text field that has your class names.

If you choose Any as your Current Class, all the pixels within your reclassify object or region will be updated to the New Class. If your class is not in the New Class drop-down list, you can click Add New Class. In the Add New Class window, fill in the information for your new class and click OK to create your class. This will allow you to create a class, similar to the image classification workflow.

The operations that can be applied to editing classified pixels are described below.

Operation	Description
Custom Processing	Apply a raster processing template (.rft.xml) to the selected region. The following two factors must be true for the operation to be successful: Both the input (raster being edited) and the output region must have the exact same properties, such as number of bands, bit-depth, and so on. The parameters in the processing template must all be valid.
Expand	Expand specified zones of the selected region by a specified number of pixels. Use Number of Cells to expand the specified zones. Use Zone Values to specify the zones you want to expand. When the Exclude Region Intersections check box is checked, any regions that intersect the active region are excluded from this operation.
Majority Filter	Use the most common value in the filter window to set the value of each pixel within the selected region. The Filter Size option allows you to choose the size of your filter window while performing the operation. A filter size of 8 means you are using an 8 by 8 filter window. Larger values result in more smoothing. When the Exclude Region Intersections check box is checked, any regions that intersect the active region are excluded from this operation.
Reclass Using Features	Integrate polygon information of a feature to reclassify your data within the selected region. Input Features—Select the feature class to convert to raster format. Field—Select the field to use to identify each feature. Resolve overlap method—Determine how to manage features that overlap: First—The overlapping areas are assigned a value from the first dataset listed. Last—The overlapping areas are assigned a value from the last dataset listed. Smallest—The overlapping areas are assigned a value from the smallest feature. Largest—The overlapping areas are assigned a value from the largest feature. When the Exclude Region Intersections check box is checked, any regions that intersect the active region are excluded from this operation.
Set NoData	Set the pixels in the selected region as NoData pixels for each band. When the Exclude Region Intersections check box is checked, any regions that intersect the active region are excluded from this operation.
Shrink	Shrink the specified zones of a region by a specified number of pixels within the selected region. Specify the Number of Cells to shrink the specified zones. Use Zone Values to specify the zones to shrink. When the Exclude Region Intersections check box is checked, any regions that intersect the active region are excluded from this operation.

You can use the Undo button to reverse the last action that was performed by the tools on the Pixel Editor tab. The undo action can also be performed by pressing Ctrl+Z; this shortcut can also be used to undo actions that were performed in the Pixel Editor Operations pane. You can use the Redo button to reverse the undo action that was performed by the tools on the Pixel Editor tab. The redo action can also be performed by pressing Ctrl+Y; this shortcut can also be used to redo actions that were performed in the Pixel Editor Operations pane.