Pitney Bowes MapInfo Professional - Manual (Page 352)

Working with Raster Images
There are a number of ways you can obtain raster image files. If you have a scanner and scanner
software, you can use the scanner to create raster image files. MapInfo Professional can read and display
the raster image files created with the scanner software.
Some graphics software packages let you save or export images into raster file formats, such as TIFF
(Tagged Image File Format). So if you can create a TIFF file with your draw or paint package, you can
display it in MapInfo Professional.
You can also purchase raster images from MapInfo Professional or other commercial vendors. Some
data vendors also offer scanning services.
Determining Map Coordinates
When registering your raster image, you need to know the map coordinates that correspond to your
image. If your raster map image shows a graticule (a grid of longitude/latitude lines), you can determine
map coordinates by noting the longitude/latitude labels along the graticule.
If your map does not show a graticule, you may be able to determine map coordinates by locating
prominent map features, for example, the Northwest corner of a region, and then using another MapInfo
Professional table as a reference to determine the coordinates of those prominent features.
For a discussion of this process, see Choosing Control Points from an Existing Map in the Help System.
An Introduction to Raster Image Registration
What Is a Raster Image?
A raster image is a type of computerized image that consists of row after row of tiny dots (pixels). If you
have a scanner and scanner software, you can create a raster image by scanning a paper map. After
you scan a map image and store the image in a file, you can display the file using MapInfo Professional.
There are many different raster image file formats. MapInfo Professional can read the following types
of raster image files: JPEG, GIF, TIFF, PCX, BMP, TGA (Targa), and BIL (SPOT satellite).
What Does It Mean To Register a Raster Image?
When you register a raster map image, you enter map coordinates (e.g. longitude/latitude degrees), and
you indicate which locations on the raster image correspond to those coordinates. You must register
each raster image before displaying the image in MapInfo Professional, so that MapInfo Professional
can perform geographic calculations, such as distance and area calculations, when displaying the raster
map.
The first time you open a raster image file within MapInfo Professional, MapInfo Professional displays
the Register Raster Image dialog box. By completing this dialog box, you tell MapInfo Professional how
to register the raster image and determine the coordinate system for the image. MapInfo Professional
stores the raster image's registration information in a table file for future re-use. The next time you run
MapInfo Professional, you can re-open the raster table without repeating the registration process. Thus,
you only need to register each raster image once.
Raster image files provided by MapInfo Professional are already registered. You do not need to perform
the registration process when you display the sample raster data included with MapInfo Professional.
MapInfo Professional 12.5 352
Working with Raster Images