QGIS/C2/Digitizing-Map-Data/English-timed

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Time Narration
00:01 Welcome to this tutorial on Digitizing Map Data in QGIS.
00:07 In this tutorial, we will learn to- Create and digitize Point and Polygon shape files.
00:15 Change style and color for Point and Polygon features.
00:20 To record this tutorial I am using-

Ubuntu Linux OS version 16.04

QGIS version 2.18

00:32 To follow this tutorial, you should be familiar with basic GIS and QGIS interface.
00:41 Digitizing is the process by which, coordinates from a map, image or other sources of data

are converted into a digital format.

00:52 The converted data can be stored as a point, line or a polygon feature in GIS.
01:00 To practise this tutorial, you need to download the thematic map of Bangalore city given in the Code files link.
01:09 This is a map depicting development of Bangalore city.
01:15 Steps to download the code files.
01:18 Click on the link Code files, located below the player and save it in your folder.
01:25 Extract the downloaded zip file.
01:28 Locate Bangalore.jpg file in the extracted folder.
01:34 I have already downloaded the Code file, extracted and saved in a folder on Desktop.
01:41 Double-click on the folder to open it.
01:45 Right-click on Bangalore.jpg file.
01:49 From the context menu select, Open with QGIS Desktop.
01:56 QGIS interface opens.
01:59 QGIS Tips dialog-box opens. Click on OK button.
02:06 Coordinate Reference System Selector dialog-box opens.
02:11 Under the heading, Coordinate reference systems of the world, Select WGS 84.
02:19 Note that WGS 84 is the most widely used geographic coordinate system.
02:27 Click on OK button at the bottom of the dialog-box.
02:32 Thematic map of Bangalore is displayed on the canvas.
02:38 Now let us create new shape file layers.
02:42 Click on Layer menu on the menu bar and select Create Layer option.
02:50 From the sub-menu, select New Shapefile Layer option.
02:55 New Shapefile Layer window opens.
02:59 Here you can see options for 3 types of features, Point, Line and Polygon.
03:10 By default Point option is selected.

Leave it as such.

03:16 Let the CRS be WGS 84.
03:21 Click on OK button at the bottom-right corner of the window.
03:27 Save Layer as.. dialog-box opens.
03:31 Let us name the file as Point-1.
03:35 Select a suitable location to save the file.

I will choose Desktop.

03:42 Click on Save button at the bottom-right corner of the dialog-box.
03:48 Files will be saved on the desktop as shown here.
03:53 Back to the QGIS interface.
03:56 Notice that the file will be automatically loaded in the Layers Panel.
04:02 On this map, we will mark the locations where IT departments are established.
04;09 Scroll the center mouse button to zoom-in.
04:14 Refer to the legend at the bottom-right corner of the map for IT establishments.
04:21 IT establishments are indicated as flag symbol.
04:26 Locate the points indicating IT establishments on the map.
04:32 There are two points indicating IT establishments.
04:37 To edit or modify features on the map, we need to select the Toggle editing tool.
04:44 Toggle Editing tool is available on the top-left corner of the tool bar.
04:51 Click on the Toggle Editing tool to select it.
04:55 Click on Add Feature tool on the tool bar.
04:59 The cursor is now displayed as a crosshair icon.
05:04 Click on IT establishment symbol on the map.
05:08 An input-box Point-1 Feature Attributes opens.
05:14 Type 1 in the id text box. Click on OK button.
05:21 Similarly click on the second IT establishment and save the feature as 2.

Click on OK button.

05:31 Now to stop editing, again click on Toggle Editing tool on the tool bar.
05:38 Stop editing dialog-box opens.
05:42 Click on Save button.
05:45 Observe, on the map, two colored point features are created.
05:51 We can check the two features created, by opening the attribute table.
05:56 Right-click on the Point-1 layer on the Layers panel.
06:01 From the context menu, select Open Attribute Table option.
06:06 In the Point-1: Features dialog-box, in id column, two points are created.
06:13 Close the attribute table dialog-box.
06:17 Style and color of these point features can be changed for clear visibility.
06:23 Right-click on the Point-1 layer.
06:26 From the context menu choose Properties option.
06:31 Layer Properties dialog-box opens.
06:35 Click on the Color drop down.
06:38 Choose a color by rotating the color triangle.
06:42 Increase the size by clicking on upward arrow triangle at the end of Size text box.
06:50 Click on OK button at the bottom of the dialog-box.
06:54 Notice the change in color and size for the Point features.
07:00 Now let us create a shape file containing Polygon features.
07:05 Click on Layer menu on the menu bar. Select Create Layer option.
07:12 From the sub-menu, select New Shapefile Layer.
07:17 New Shape File Layer window opens.
07:21 Select Type as Polygon.
07:25 In the New field Name text box, type area.
07:31 Let the Type be Text data.
07:35 Click on Add to fields list button
07:40 In the Fields List table, you will see area row added.

Click on OK button.

07:50 Save layer as.. dialog-box opens.
07:54 Type the File name as Area-1.
07:58 Select a suitable location.
08:01 I will select Desktop. Click on Save button.
08:07 Notice that Area-1 layer is added to the Layers panel.
08:13 We will mark the boundary of Corporation Area and Greater Bangalore area.
08:20 Refer to the Legend on the map to locate Corporation area and Greater Bangalore area.
08:28 Turn on the toggle editing by clicking on Toggle Editing tool on the tool bar.
08:35 Click on Add Feature tool from the tool bar.
08:39 Bring the cursor to the map.
08:42 To mark the area, click anywhere on the boundary of Corporation area.
08:48 Keep clicking on the boundary.
08:51 Warning messages may appear at the top of the canvas if the line segments intersect.

Please ignore these messages.

09:02 If you make a mistake and want to restart the marking process, press Esc Key on the keyboard.
09:10 You can start the process again.
09:13 Keep clicking on the boundary till you span the entire boundary.
09:24 Once you have marked the entire boundary, right-click to end the polygon.
09:30 Area-1- Feature Attributes input box opens.
09:36 Type 1 in the id text box.
09:40 Type Corporation Area in area text box.
09:45 Click on OK button.
09:48 Observe, on the map new polygon feature is created.
09:54 Now we will digitize Greater Bangalore region in the map.
09:59 Click on the boundary to digitize Greater Bangalore region as shown here.
10:12 After you finish digitizing, right-click to end the polygon.
10:18 In the Area-1 Feature Attributes text box, type 2 in the id text box.

And Greater Bangalore in the area text box.

10:30 Click on OK button.
10:33 Again click on Toggle Editing tool in the tool bar to stop editing.
10:39 Click on Save button in the Stop editing dialog box.
10:44 Right click on Area-1 layer to open attribute table.
10:49 Select Open Attribute Table from the context menu.
10:54 We can see that 2 features have been created with columns id and area type.

Close the attribute table.

11:04 We can see that two polygon features have been created.
11:09 To change the color and style of polygon feature, right click on Area-1 layer.

Select Properties option.

11:19 In the Layer Properties dialog-box, select Style option from the left panel.
11:26 On the top left corner of the drop down menu, select categorized.
11:32 In the column drop down select id.

Click on Classify button.

11:39 Move the Layer transparency slider to 50 %.
11:44 Click on OK button at the bottom of the dialog-box.
11:49 Now on the map, we can see that the two Polygon features are in different color.
11:55 Details about labeling the features, will be discussed in upcoming tutorials in the series.
12:03 Let's summarize.
12:05 In this tutorial we have learnt to, Create and digitize Point and Polygon shape files.
12:13 Change style and color for Point and Polygon features.
12:18 As an Assignment, On the Banglaore thematic map (Bangalore.jpg),

Digitize Industrial Estates Digitize the roads on the map, by creating a Polyline feature.

12:32 Your completed assignment should look as shown here.
12:37 The video at the following link summarises the spoken tutorial project. Please download and watch it.
12:45 The spoken tutorial project team conducts workshops and gives certificates on passing online tests

For more details please write to us.

12:57 Please post your timed queries on this forum.
13:01 The Spoken Tutorial Project is funded by NMEICT, MHRD Government of India.

More information on this mission is available at the following link.

13:13 This tutorial is contributed by Prajwal.M from Sahyadri college of Engineering and Snehalatha from IIT Bombay.

Thank you for joining.

Contributors and Content Editors

PoojaMoolya