index transform file (*.itr)

Index transform (ITR) files are used to map colours to data values. Colour table files simply contain colour values whereas Index Transform files contain colours and mapping numbers. ITR files tell the system to map a certain range of values to a specific colour. Normally, ITR files (*.itr) are created automatically when you change the colour zoning and you can save specific configurations to ITR files for reuse.

Using the Colour Tool you can save a customised ITR file, or load previously created files.

The Transform buttons on these tools enable you to save a particular colour zoning scheme you have created, to load a saved zoning scheme or to restore the default scheme. For instance, if you manipulate the colour palette interactively, you can save your new palette scheme to an ITR file. Similarly, if you define divisions manually based on percentiles, for instance, you can save this new scheme for future use.