Let us consider a color round to make it clear (Fig. 1). You are earnestly advised to load this raster from our site (see Download) and fulfill all the operations by yourself.

1. Load the ColorCir.tif raster to Easy Trace: File > Open Raster
2. Click the button in the Tool bar to start the mode of raster binarization.
3. Click the mouse right button and then the button of the submenu to switch the histogram on.
4. Take the tool for color set creating from the Control bar of the Binarization tool (below the working window).
5. Click any point within the color round. A polygon appears around it. Its shape and area depend on the "Color scattering in manual mode" parameter of binarization setting (see Fig. 2). The polygon shows colors belonging to the new-created mask.
6. Move one boundary of the histogram with your mouse - note movement of the polygon corresponding side.

Specify other points in the color round to add new color ranges (masks) to the current color set.The tool for color set subtraction resembles the tool for color set creating, but it deletes the ranges you have selected from the set (as if they have negative values). You may see the result in the color round.You may create masks of any complexity combining these tools.

To start the "Mask Autoexpansion" mode, use the button on the Binarization tool's control bar. When this mode is on and you select a new color, the program tries to expand one of the existing masks so that it would comprise the specified color (Fig. 3). If it fails to do it, a new mask will be added to the set.

A typical example of relief layer separation from a scanned topographic map is based on the Sample.tif image file.

1. Load the Sample.tif raster to the program: File > Open raster

2. Click the button on the tool bar and start the raster binarization mode.

3. Click the mouse right button within the program working window and then the button in the submenu to switch the histogram on.

4. Create a new thematic layer applying the binarization tool's control bar (Fig. 3).

5. 5. Use the Zoom tool to magnify the raster on your screen up to the scale large enough to see its pixel structure distinctly (Fig. 5).

6.Select the tool for color set creation and use it to make masks on a relief isoline.Select colors in the zones shown in Fig. 5. Switch on the Mask autoexpansion mode top avoid creating of too many masks. (Fig. 4). 7. Control the quality of color layer separation. To do it, switch yje color raster off with the B button on the Binarization tool's control bar (Fig. 4).Switch on the Current mask mode (the M button is "pressed") and look through all the new-created masks one after another. Select one corresponding to the best isoline presentation and try to make them even more distinct by mask width changing with the help of the histogram (Fig. 6). Try to do the same operation with other masks. Start the Thematic layer mode (the F button is "pressed") and apply the tools for mask creating and subtraction to decrease the number of gaps in lines and "bridges" between them (Fig. 6).

8. Make the color raster visible for additional check of thematic layer separation. Don't try to avoid thin lines - 1 px wide lines are suitable for tracing tools. Small gaps in lines are also admissible. "Bridges" between lines are mush more undesirable. The thematic layer fragment represented in Fig. 7 is fairly good.

9. Click the mouse right button within the program working window and then the button of the submenu to transform the masks into a black-and-white raster.

10. Decrease the noise in the new-created raster with the help of the "Raster Cleaning" tool - icon of the main tool bar. Repeat this operation several times if necessary.

11. Save the thematic black-and-white raster: File > Save as

It is convenient sometimes "to move counter": to select (applying masks) the colors that should not be included to the thematic layer. This method differs from one stated above only at the last stage - after noise deletion (step 10) the image should be inverted (click the button of the tool bar).