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The various steps of the exercise will be shown for the Rainforest zone only.

In order to crop an area within the coordinates specified, we need to know their equivalent in rows and columns, because LEOWorks crops images using those parameters. The order in which the cropping is performed on the images does not matter. Let’s start with the image for the month of January.

• Open the TIFF image: File/Open/*.TIFF (Year2000.tiff)
• Open the whole image and convert it into an image with LUT (Image/Covert to/Image with LUT).
• A colour bar will appear at the bottom of the image. Click twice on the bar and the LUT Editor will appear. The LUT Editor allows you to change the colour palette to a more ‘realistic’ one.
• Click on Open LUT and pick the ndvi.pal file. The .pal extension tells us that this file is an ASCII file that contains a table of numbers. Each of the 256 lines are separated into three columns and have values that range between 0 and 255. Each value corresponds to a different colour.
• Click on View/CursorPosition_Value. A small dialog box containing information about numbers for X, Y, Latitude and Longitude, as well as the value of the pixel (screen data and original data) will open.
• Zoom into the area of interest. Look for the approximate coordinates and their equivalent in number of rows and columns. For instance, to represent the biogeographical zone of the rainforest, we have chosen an area in Brasil. Look for the four corner coordinates using the cursor position/value tool. Once you have the corner coordinates, make a note of the number of rows and columns.
• Start the subset. Choose the Image/Crop tool and assign the values found. In the rainforest case we assign left=673, right=897, top=449, bottom=673. We can save the results as a .tif image using File/Save as (1_rainforest.tif). The new image has 225 rows x 225 columns, and the geocoding is kept.
• Repeat this process for the twelve months and for the different areas we want to split.

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