Raster files often have a well-known extension describing the data format they contain, such as .jpg. If a raster's data is in a format supported by ArcGIS but its file extension doesn't appear in the Raster tab's list, it won't appear when you choose to view a list of files. For example, by default, only files with the extension .tif are recognized as TIFF images—but those with the extension .tiff are not. You can customize the list of file extensions that are associated with a raster format.
Not all rasters have file name extensions, and some are stored as folders. Because identifying such rasters takes more time, they are skipped by default when searching a folder's contents. Therefore, they won't appear in the file list. The exception is the Esri Grid format, which is quickly identified in a search even without a file name extension. By default, ArcGIS always searches for grids. If you choose to search for all rasters, the file lists will be slower to appear, but all rasters in all folders will be accurately listed.
A list of the raster formats that can be directly accessed by ArcGIS Desktop is accessible from the application's Options dialog box on the Raster tab. You can also find this list in Supported raster dataset file formats. At times, you may not want to see all the types of rasters when viewing the contents in ArcCatalog, the Catalog window, or when choosing a raster dataset to add in ArcMap, ArcScene, or ArcGlobe. For example, data can be stored in different formats, and you want to work with only one of those formats at a time.
To reduce the time it takes to list all the supported raster formats you have on disk, you can change the default list to only check for a specific set.
Additionally, if you have a valid raster format that does not have a standard file extension, such as an ARC Digitized Raster Graphic (ADRG) legend file, you can modify the file extension that will be searched for by selecting it in the format list and entering the new file extension.
- You can access the Raster File Formats Properties dialog box from the Customize menu in the ArcGIS Desktop applications.
- In ArcMap (ArcGlobe or ArcScene), click the Customize menu, click ArcMap Options, click the Raster tab, click the Raster Dataset tab, then click File Formats.
- In ArcCatalog, click the Customize menu, click ArcCatalog Options, click the General tab, click Raster Files in the data types list, then click Properties.
- Click Search only files that match the following file extensions to find valid raster formats.
- Uncheck the raster formats you don't want to see listed or check the raster formats you want to see listed.
- Click OK to close each dialog box.