5.4.8 Digitize lines in Google Earth
Level of expertise required for this Chapter: Advanced; general Map Maker training
Before you start digitizing, you have to check, if Google Earth is installed, its resolution is good enough to recognize all structures and the horizontal accuracy is better than 10 m (for example, against the GPS). If these criteria are not met, digitizing is not recommended.
1. In Google Earth:
Load Google Earth > Zoom to area of interest (You can zoom in by +, out by -, move in all four directions (N, S, W, E) with the arrow keys. The indicated altitude should not exceed 3 km) > Add (1, see below) > Path > Google Earth – New window: Give name (2, see below) > Start digitizing by clicking the mouse on each bend, thus creating vertices.
If you like to change a digitized point, you can locate the point, and drag it to a new position. Afterwards, you have to click on the last point to continue with digitizing.
At the end of the line, you press Ok at the bottom >
> In ‘Places’ on the left side, you will find the newly created layer (under ‘My places’) > right-click > Save As … , or Save place as … > Save as type: KML > Select folder > Accept or rename file name > Save
If you want to edit a line after having finished digitizing, you click right-mouse on this track in ‘Places’ > Properties, and you are back to the editing mode. After having closed the line, do not forget to save it again as KML file.
After this step 1, you have two alternatives to proceed and to convert the KML file to Map Maker:
Either with step 2 using the LUPMIS Tools or with step 2-4-ALTERNATIVE using GPSUtility software. Both of these alternative steps are explained below.
2. If you have LUPMIS Tools, the preferred option is the tool 'Import KML' of the Drawing Tools. This will directly convert the KML file to a DRA file, and also convert it to UTM, if the KML file is in lat/long (as digitized in Google Earth).
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2-ALTERNATIVE. With the software GPSUtility, convert KML file to SHP file. (See Annex 7 for utilities).
Load GPSUtility > License conditions for GPS Utility window: Yes (You can OK any other messages before that) > GPSUtility window: File > Open > Open window: Select Files of Type: Google Earth (kml, kmz) > Select folder and file > Open > Confirm window: Yes >
The imported data display should like this:
> File > Save/Export options > Save / Export / Print Options window: Select Format: Shape fileset (SHP+SHX,DBF)(1, see below) > Export As (2) >
> Save as window: Select folder > Specify file name > Check, that specified file type is still SHP etc > Save. Finished! > File > Exit
3-ALTERNATIVE. In Map Maker, convert SHP file to DRA file: Main menu > Utilities > Vector utilities > Import file > ArcView Shape file > Step 1 of 3 window: Choose source SHP file > Select folder, file > Open > Next step > Step 2 of 3 window: Use serial number as object ID > Next step > Step 3 of 3 window: Choose target file > Select folder > Accept or change file name > Save > Finish > Confirm save
Finished! For checking purposes, you then download this file in Map Maker by: Right-mouse > Add layer > Select folder and file (DRA file) > Open > OK. You should be able to see your digitized line. Then, Main menu > File > View in Google Earth, to see and check it with the original feature.
4-ALTERNATIVE. In Map Maker, you will, see if the imported line is in latitude / longitude or in UTM. If in lat / long, you must project it to UTM (see Chapter 5.2.4).