Introduction to Digitizing

Introduction to Digitizing

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Digitizing is the process of converting geographic features on a paper map into digital format. The x, y coordinates of point, line and polygon features are recorded and stored as the spatial data. The feature attributes are also recorded during the digitizing process. It is the most common and labor intensive method to create a spatial database. The method is used especially when existing maps are available as the source of data. Coordinates of point features, line features and polygon features are recorded by manually pointing or tracing, using a digitizer table and cursor. The cursor position is accurately measured, by the device in order to generate the coordinate data in digital form. Although digitizing is substituted by scanning, digitizing tablets are still used to convert existing maps and drawings into GIS. Digitizing tablets typically support E-Size and larger drawings, with 0.001-foot resolution, 0.001-foot repeatability and 0.005-foot accuracy. Remember that, digitizing contributes to error.

Step-1 Setting Up The Digitizer

Go to the Step by Step Animation. See the Step 1.

Step-2 Preparation of the Map for Digitizing

Go to the Step by Step Animation. See the Step 2.

3. Create the Common TIC file

Go to the Step by Step Animation. See the Step 3.

4. Register the control points

Go to the Step by Step Animation. See the Step 4.

5. Digitizing Point Feature

Go to the Step by Step Animation. See the Step 5.

6. Digitizing Line Feature

Go to the Step by Step Animation. See the Step 6, 7 and 8.

7. Digitizing Polygon Features

Go to the Step by Step Animation. See the Step 9, 10 and 11.