In this example we are going to keyboard digitize a profile from a two dimensional image. This method can be used for route location studies prior to a preliminary reconnaissance of a road or for determining proposed deflection line locations.

1. Import the image into the Terrain Module. The image can be *.bmp, *.jpg, or *.tif format (image available at http://www.softree-espanol.com/images/topo_2_pro.bmp ).

1. From menu Edit|Digitize/Draw New Feature, turn on Elevations and Press the Draw button.
2. In the resulting dialog box change the Elevation to 175 and the interval to 5.
3. In this example the starting point is station 0 shown at the bottom of Figure 1.
4. Press E on your keyboard. This will bring up the Modify Current Point Coordinates dialog.
5. Change the Z: value to 172
6. Press the Update List button and then press OK.
7. A Point will be added at station 0 on the bitmap.
8. Place the pencil cursor over station 150 on the bitmap and press E again.
9. This time change the Z: value to 175.
10. Press the Update List button and press OK.
11. A point will be added at station 150.

From here on in we can press the 8 key (Up one interval) the 5 key (Same elevation) or the 2 key (Down one interval).

12. Place the cursor over station 230. Press 8.
13. Place the cursor over station 275 and press 5.
14. Keep doing this at every station until you reach 900.
15. Lets look at the profile of what we just drew with menu Window/New Window/Profile. The figure below will appear.

Notice that the horizontal distance in the profile is different than the horizontal distance on the bitmap. The former has a horizontal distance of 1034.4 and the latter has a horizontal distance of 900. This means that our bitmap image is at an incorrect size.

Dividing the horizontal distance of the drawn line into the horizontal distance of the line on the bitmap will give us a number with which we can resize our image.

900/1034.4 = 0.8701

1. Select the bitmap image.
2. With menu Edit/Modify Selected Feature(s)/Properties, change the X and Y Pixel sizes to the one calculated above. Press OK.

Notice that now the drawn line is not a correct size.

3. Select the line.
4. With menu Edit/Modify Selected Feature(s)/Move/Size, a box will appear around the line. Move and resize the line so that it is again coincident with the bitmap line.

Notice that the profile horizontal distance is now very close to the bitmap horizontal distance of 900.

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