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Use this command, located on the Tools Menu > Import/Export Menu, to add background raster images to your map.
To import images:
1) From the main menu select Tools - Import/Export - Import Images
2) Select a destination layer for the new images. If the layer already contains some images see DataDirectory note below.
3) Using the browse window select one or more files to be imported. To select all the images in a directory highlight one of the image files and then press Ctrl-A. Or hold down the control key while selecting the individual files.
4) Specify the units that the pixels are measured in.
How images are stored:
Most maps contain at least one imagery layer such as "ortho-photography". An imagery layer typically consists of several rectangular images all tiled together to form a seamless picture of a large area. This is accomplished by storing in the layer a reference to each image. The images themselves, which are typically very large in file size, remain stored in their own individual files. During the import process a new feature is created containing the name of each file. The Data Directory property for this layer is automatically set to this directory.
For each image feature on the layer, an image entity is placed on the map marking the location of the image. The location of the image is determined from the world file accompanying each image file.
Notes:
•Think GIS supports the following types of images:
•MrSid images (Generation 2 & 3)
•TIFF images (including tiled tiff's and JPEG compressed tiff's)
•Uncompressed 256 color BMP images
•Uncompressed black/white BMP images
•JPEG2000 images
•ECW images
•Each image file must be accompanied by its corresponding world file (ie. .sdw, .tfw, .jgw, .if, or .hdr) which tells Think GIS where to place this image on the map. Once the images are imported the world files are no longer needed. For MrSid images, Think GIS first looks for an .sdw file and if one is not found it retrieves the world location from the sid file itself. ECW images do not require a world file.
•The import process assumes that each image is already projected in the same Projection as the currently open map.
•See also place image button for placing individual images (world referenced or not)
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