Georeferencing & Digitizing

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  • 1. Fill all the coordinates from lab manual into excel spreadsheet. Do not make a border for table and

    make sure column and row height is set to auto. This step to ensure that arcgis toolbox will not

    encounter an error during converting the table file into database file (dbf).

    2. Save the spreadsheet as Text (MS-DOS)

  • 3. Open Arcgis catalog, click arcgis toolbox and click the Table to dBASE (multiple) to convert table file

    to (dbf) format.

    4. New tab appear, at Input Table, click browse and find text file we already save from Microsoft excel.

    At Output Folder, choose desired personal folder to save dbf file location.

  • 5. When conversion complete, the pop up notification appear at the bottom of window taskbar to

    notify either it is success or failure. Now we want to convert the dbf file into shapefile, right click at

    dbf file, click Create Feature Class and click From XY Table .

    6. New tab appear, click browse and change save as type as shapefile rename it as pollution.shp and

    click save.

  • 7. Now we already done the task 1, we can proceed on the task 2. According to the task 2, we need to

    specify the coordinate system of pollution shapefile, if we try to add this layer at arcmap, arc map

    will display an error message. Unknown spatial reference warning will pop up indicate that the

    pollution shapefile does not have a projection definition which mean the coordinate system is

    unidentified. Thus, to add the coordinate system for specified data, simply right click at pollution

    shapefile and click properties.

    8. Click the XY coordinate System Tab, according to the Lab Manual, we need to choose the WGS

    1984 UTM ZONE 47N as the coordinate system for pollution shapefile under projected coordinate

    system. After done choosing click apply and ok.

  • 9. Same instruction as step 8, specify the coordinate system for zoning warta as a basemap, choose

    Kertau RSO Malaya (Meters) in case if it is not specify yet.

    10. Now we can test either both layer pollution shapefile and zoning_warta (basemap) are match in

    term of their location. Open arcmap and choose new template, before adding both layer, since both

    layer has a different coordinate system, we need to specify the correct datum for both layer in

    arcmap by clicking at View, click Data Frame Properties and click Coordinate System tab. Choose

    Kertau RSO Malaya (Meters).

  • 11. Now both layer are match together, we can identify the coordinate for each points of pollution data

    by clicking identify and click at the blue point appear on the map. Record their coordinate on the

    table.

    12. Now we already done step 2 4, we can proceed to the step 5. Now we will learn how to digitize

    the zoning warta layer for new feature class with non-data recorded. This time we will need to add

    satellite image which already provided (port_klang.jpg) as a reference to gather information

    involving landuse and road network for digitizing. First, create new personal geodatabase and

    create new feature class for landuse and road. For Landuse, choose polygon type and line for road.

    Also specify the coordinate system and add Name at attribute section for both feature class.

  • 13. Now add both feature class data (landuse and road) into the arcmap. We can try to zoom layer for

    landuse, we will notify that there is no data provided on the screen, this is what will do, we will

    create the data by digitizing the zoning warta layer with satellite image (port_klang.jpeg) as a

    reference. Before that, we will need to match the location of port_klang image and zoning warta

    together by georeferencing technique. This will register the port_klang image so it is in the same

    geographic space as the zoning warta layer.

    14. Add the port_klang image to the arcmap. The unknown spatial reference error will be display, again,

    this mean the port_klang image consist no coordinate system. Just click OK.

  • 15. Now click Find, type port klang and click Find. Once the searching is finished, right click at the port

    klang berhad and click zoom to. Try to zoom out a bit and find the exact location of satellite image

    in zoning warta layer. Once we find the location, click create bookmark and add port klang. This will

    assist us during georeferencing later. We also might need to use magnifier to assist us in

    georeferencing.

  • 16. Click Customize > Toolbars > georeferencing

  • 17. Using the magnifier, try to point the cross mark of magnifier at the corner of the road as shown in

    picture below.

    18. Now we are ready to start the georeferencing, click add control points, the cross mark will appear,

    same with step 17, point the cross mark at the corner of the road and left click. Once click, the cross

    mark colour will turn to green indicate that 1st control point has been added. Now we will need to

    add the next control point at the same location but this time at the zoning warta layer.

  • 19. Use the bookmark we already made, click port klang.

    20. Same as the step 17-18, using the magnifier, try to point the cross mark of magnifier at the corner

    of the road as shown in picture below. Then, point the cross mark at the corner of the road and left

    click. Once click, the cross mark colour will turn to red indicate that link of 1st control point has been

    added.

  • 21. The port klang image is actually already moved at the behind of zoning warta layer. We will need to

    change the fill colour to no fill and choose the desired outline colour to assist us in digitizing. The

    result should be the same as picture below.

  • 22. Now we can begin to add next control point, the step is same as before. Put at least 3 control point

    to achieved best result. After we done with georeferencing, click update georeferencing. The

    example of end result is shown below:

  • 23. Now we can start the digitizing process, click editor toolbar > click start editing > Choose Landuse >

    Click Continue. The polygon is now ready to digitize.

  • 24. Click Create Features > Click Landuse . Now we can begin digitizing for landuse, in this case, we will

    add the data of Sekolah Jenis Kebangsaan (C) Pandamaran for landuse as the information was

    provided by google map.

  • 25. Begin digitizing, click at each edge of the boundary. Once finish, right click and click Finish sketch.

    26. Now Click attribute > add name: Sekolah Jenis Kebangsaan (C) Pandamaran for basic information of

    landuse created. To view the label, right click at landuse layer and click label features. To finish the

    editing, click stop editing and save our edit.

  • 27. Figure below is the end result of digitizing process, digitizing process for road is same as landuse.