Saving to a GeoTIFF - MapInfo_Pro - 2023

MapInfo Pro includes the capability of exporting Map windows to GeoTIFF (*.tif) export format. GeoTIFF files are designed to connect a raster image to its location on the earth. Georeferencing information is written directly to the *.tif file so that it can be used in other applications. This section explains the requirements for exporting maps to GeoTIFF format. Using GeoTIFF format has the following requirements:

• The window you are exporting is a Map window.
• The Map window's projection contains an EPSG code. Projections that do not have an EPSG code are not supported.
• The Map window must not be rotated, or contain a raster image that causes a rotation.

To save a Map window to a GeoTIFF format file, do the following:

1. Open the desired layers in a Map window, if you do not have your map open already.
2. Make the Map window active.
3. On the HOME tab, in the Output group, click Save Image to open the Save Window to File dialog box.
4. In the Save in box, select the destination folder of the exported file.
5. In the Save as type drop-down list, click the arrow to see the file format choices. Select GeoTIFF (*.tif).

   GeoTIFF is not available as an export format for other types of windows (such as Browser, Legend Designer, or Redistricter) or Map windows that use unsupported projections.

6. In the File name box, enter a name for the exported file.
7. Click Save and continue with the normal Save Window As process.
8. In the Save Window As dialog box, either keep the default window size for your image (Same as Window) or select a custom image size (Custom).
9. Click Save to create the image.

Supported Projections and GeoTIFF

When you save a Map window to GeoTIFF format, the file is saved in the current projection of the Map window. You cannot use the Save Window As command to save the Map window to a different projection. Instead, you must change the Map window projection before you use the Save Window As command. You can select a projection in the Choose Projection dialog box.

To change the projection, on the Layers or Explorer windows, right-click on the map name and select Map Options. In the Map Options dialog box click Projection. In the Choose Projection dialog box, select the projection from the Category and Category Member lists.

The Map window projection must have an EPSG code. You can see whether a projection has an EPSG code in the Choose Projection dialog box. To do this, on the Layers or Explorer windows, right-click on the map name and select Map Options. In the Map Options dialog box click Projection. In the Choose Projection dialog box, select the projection from the Category and Category Member lists.

If you attempt to save a Map window using a projection that is not supported by the GeoTIFF format, that is, a projection that does not have an EPSG code, the GeoTIFF format will not be available as an export format. In addition, the Save Window As dialog box displays the following message at the bottom of the dialog box:

GeoTIFF option not available when Current Map Projection does not have an EPSG code. In order to save to GeoTIFF, you will need to change your map projection to one that has an EPSG code.

Image Rotation and GeoTIFF

In Map windows that contain a raster or grid image, the image must not cause the map projection to rotate the coordinates if you wish to create a GeoTIFF for this Map window. Rotation can occur if the image is not registered precisely. To work around this, you can force Image Reprojection to be enabled.

To do this, on the Layers or Explorer windows, right-click on the map name and select Map Options. In the Map Options dialog box click Image Processing. In the Image Processing dialog box, select Always under Reprojection Using.

If Image Processing is set to Always, then it is possible to use raster layers for GeoTIFF export.

Saving Raster and Grid Images to GeoTIFF

If you attempt to save a Map window that contains a raster or grid image that causes a rotation in the Map window, the GeoTIFF format will not be available to save to. In addition, the Save Window As dialog box displays the following message at the bottom of the dialog box:

GeoTIFF option not available when Map projection is rotated due to raster or grid images.

Turn on Image Processing. On the Layers or Explorer windows, right-click on the map name and select Map Options. In the Map Options dialog box click Image Processing. In the Image Processing dialog box, select Always under Reprojection Using. Save the Map window to GeoTIFF format again.