Digitization

 

                                                                                                                                                                    Back to ADV GIS

 

This process consisted of digitizing the district boundaries. The district boundaries were obtained from Atlas of India by Oxford University Press (1990). The digitization was followed by cleaning and building the polygons. The following steps were used for this purpose;

 

 

1. Be sure both the PC and the monitor (Fig. 1) are turned on.

 

Figure 1.  PC attached with the digitizer in GIS and Remote Sensing lab at the Department of Geography, KSU.

 

 

2. Turn on the digitizer (Fig. 2). You will hear three beeps if digitizer is working properly.

 

Figure 2.  Sumagrid digitizer.

 

3. Open Arcedit

 

4. Select working directory

            Arcedit: &workspace “directory name” e.g. z:\

 

5. Coordinate digitizer

            Arcedit: digitizer sgmg3 com1:9600:7bit:even

            Arcedit: coordinate digitizer

 

6. Create coverage

            Arcedit: create "file name" e.g. southasia

 

If you are using an old coverage;

            Arcedit: mapex "file name" e.g. southasia

 

            Arcedit: edit "file name" e.g. southasia

 

Kill "file name" can be used to delete an existing coverage

 

7. Entering Tic ids

Place the digitizing keypad (Fig. 3) on the desired point and enter tic ids followed by "A" "1" e.g. press 6 9 followed by “A” “1”

           

Enter the next ids in the same manner.

                                                                                                                                                                            Back to Top

When finished enter "0" "A"

 

Figure 3.  Digitizing keypad.

 

 

8. If creating a new coverage, the program will ask u to define the box after entering the tic ids.

Click on two opposite corners slightly larger than the map, using "1" on the keypad.

 

9. Begin digitizing

            Arcedit: drawe arc label tic ids node

            Arcedit: draw

            Arcedit: editf arc

            Arcedit: add

 

10. Add arcs

            Place the keypad on the desired line

            Make a slight overshoot on both ends of the line

            Click 2 to start and end a line and repeated "1" to draw the line

            When finished click "9"

11. Labeling polygons

            Arcedit: editf label

            Arcedit: add

           

On keypad press "8" "1" and enter label id followed by "A" "1"

 

12. Save changes

            Arcedit: save

 

13. Clean the arcs

            Arcedit: clean

 

 

14. Build the polygons

            Arcedit: build

 

15. Quit the Arcedit

            Arcedit: quit

                                                                                                                        Back to Top