How to perform crop raster data using Global Mapper are able to use the shapefile or other vector data type polygon. The main requirement for the crop in accordance with the user wants or according to the data vector is to select it (selection) first. Raster data will be in accordance with the crop area that is already in the selection. Selection of vector data can be done with the Digitizer Tool or feature Info Tool.
If you crop an area of more than one (as exemplified in this video) or multiple areas, then the selection of vector data using the Digitizer Tool should, because it features Tool Info can only select one area only. Once the selected vector data, process the crop can be done from the menu File -> Export Raster & Elevation Data -> select the type of file format you want. In the wizard that opens a window to move the Export Bounds tab, select the very bottom of the Crop Area To Selected Feature (s). More can be viewed at the following video (full screen view better by clicking the sign to the left writing Screenr)