Difference between revisions of "Working with background imagery"

From Wikiagro.com
Jump to: navigation, search
Line 1: Line 1:
{{RelatedCourse|[[Setting_up_your_farm_or_land_project|Setting up your farm or land project]]}} One of the first steps in your farm/land project is to access background imagery.
+
{{RelatedCourse|[[Setting_up_your_farm_or_land_project|Setting up your farm or land project]]}} One of the first steps in your farm/land project is to access background imagery.  
  
Online Imagery is available as a 'WMS Service'. WMS stands for Web Map Service - a standard protocol for serving georeferenced map images over the Internet that are generated by a map server using data from a GIS database.  Please visit this [http://en.wikipedia.org/wiki/Web_Map_Service '''WMS Article'''] for more information.
+
Online Imagery is available as a 'WMS Service'. WMS stands for Web Map Service - a standard protocol for serving georeferenced map images over the Internet that are generated by a map server using data from a GIS database.  Please visit this [http://en.wikipedia.org/wiki/Web_Map_Service '''WMS Article'''] for more information.  
  
 +
<br>
  
 +
=== Start a project in Iowa  ===
  
=== Start a project in Iowa ===
+
First, create a sample project using the State of Iowa dataset, as detailed in '''[[Create a Project and add data|this tutorial]]'''
  
First, create a sample project using the State of Iowa dataset, as detailed in '''[[Create_a_Project_and_add_data|this tutorial]]'''
+
<br>
  
<br>
+
=== Accessing available Imagery&nbsp; ===
 
+
=== Accessing available Imagery&nbsp; ===
+
  
 
<br>  
 
<br>  
Line 19: Line 19:
 
#Click on the 'VE Imagery' Layer to turn on Imagery from Bing Maps<sup>®</sup>. If it doesn't refresh, use the Pan tool [[Image:GIS gis Navi 02 01.jpg|Image:GIS_gis_Navi_02_01.jpg]] to move the view a bit, and refresh the imagery.You should now see aerial imagery from Bing Maps<sup>®<br>[[Image:Adding imagery 01a.jpg|border|center|640px|Iowa Bing Maps®]]</sup><br>
 
#Click on the 'VE Imagery' Layer to turn on Imagery from Bing Maps<sup>®</sup>. If it doesn't refresh, use the Pan tool [[Image:GIS gis Navi 02 01.jpg|Image:GIS_gis_Navi_02_01.jpg]] to move the view a bit, and refresh the imagery.You should now see aerial imagery from Bing Maps<sup>®<br>[[Image:Adding imagery 01a.jpg|border|center|640px|Iowa Bing Maps®]]</sup><br>
  
You can, alternatively, use the 'Imagery - NAIP' Layer from the USDA National Aerial Imagery Program (NAIP) and 'Imagery - EDRG' layer to see the available Topography scanned sheets (EDRGs or Digital Raster Graphics). There are still issues in connecting with these sources so you may or may not see it depending on the location you are working on.<br><br>[[Image:Adding imagery 02.jpg|frame|center|640px|Adding imagery 02.jpg]] <br>
+
You can, alternatively, use the 'Imagery - NAIP' Layer from the USDA National Aerial Imagery Program (NAIP) and 'Imagery - EDRG' layer to see the available Topography scanned sheets (EDRGs or Digital Raster Graphics). There are still issues in connecting with these sources so you may or may not see it depending on the location you are working on.
  
[[Image:Adding imagery 03.jpg|frame|center|640px|Adding imagery 03.jpg]]
 
  
====  ====
 
  
==== Accessing Imagery available from other WMS Sources  ====
+
'''Turning on layer 'Imagery - NAIP':'''<br><br>[[Image:Adding imagery 02.jpg|frame|center|640px]] <br>
  
This option will be useful as more imagery become publicly available on the internet as a WMS service. These may be provided by government or private organizations. A list of WMS Sources that you may use in GeoAgro GIS is available [[WMS_data_Sources|here]].
+
'''Turning on layer 'Imagery - EDRG' (Digital Raster Graphics - Topography layer) :'''
  
#On the right panel, click on the Create New Layer option [[Image:GIS gis Edit 01 01.jpg|Image:GIS_gis_Edit_01_01.jpg]]. Add a WMS Layer, by following&nbsp; these [[Create a WMS layer (Web Map Server)|'''instructions''']]. We are going to add an example of low resolution image available from NASA. Enter the following values:<br>'''<br>'''* Name: "NASA Global Mosaic" <br> * Group: "Base Map" <br> * URL: "http://wms.jpl.nasa.gov/wms.cgi?" <br>'''<br>'''
+
[[Image:Adding imagery 03.jpg|frame|center|640px]]  
#Your project should look like this[[Image:Screen NASA global mosaic.jpg|center|640px|Screen NASA global mosaic.jpg]]<br>
+
  
==== Saving your imagery to work offline ====
+
====  ====
  
It's very important to be able to work with imagery offline. Once you have selected your project area, it's a good idea to save the imagery (aerials, topo or other) as offline layers, which will provide faster performance, or the ability to work disconnected from the internet from the field or other disconnected locations.
+
<br>
  
For this purpose you can follow the steps in this article: [[Save WMS image|'''Save the WMS image to use it offline''']].
+
=== Saving your imagery to work offline ===
  
==== Related Articles  ====
+
It's very important to be able to work with imagery offline. Once you have selected your project area, it's a good idea to save the imagery (aerials, topo or other) as offline layers, which will provide faster performance, or the ability to work disconnected from the internet from the field or other disconnected locations.
  
*[[Create a WMS layer (Web Map Server)|Add a WMS layer]]
+
==== <span class="Apple-style-span" style="font-size: 13px; font-weight: normal; ">For this purpose you can follow the steps in this article:&nbsp;[[Save WMS image|'''Save the WMS image to use it offline''']]</span> ====
*[[Save WMS image|Save a WMS image to use it offline]]<br>
+
*[[WMS data Sources|Available WMS data Sources]]<br>
+
  
{{Warning|WMS layers availability depends on external servers. This means that there may be times when WMS layers are not available}}<br>  
+
==== <span class="Apple-style-span" style="font-size: 13px; font-weight: normal; ">[[Save WMS image]]</span> ====
  
----
+
=== Accessing Imagery available from other WMS Sources  ===
  
=== Exercise 02 - Downloading Soils from Web Soil Survey  ===
+
This option will be useful as more imagery become publicly available on the internet as a WMS service. These may be provided by government or private organizations. A list of WMS Sources that you may use in GeoAgro GIS is available [[WMS data Sources|here]].
  
You can use GeoAgro GIS to download soils information directly from the Web Soil Survey, using the WFS Tool. WFS stands for Web Feature Service, and Open Standard that allows to retrieve geographic features from online servers you may visit this [http://en.wikipedia.org/wiki/Web_Feature_Service '''WFS Article'''] for more information.<br>  
+
#On the right panel, click on the Create New Layer option [[Image:GIS gis Edit 01 01.jpg|Image:GIS_gis_Edit_01_01.jpg]]. Add a WMS Layer, by following&nbsp; these [[Create a WMS layer (Web Map Server)|'''instructions''']]. We are going to add an example of low resolution image available from NASA. Enter the following values:<br>'''<br>'''* Name: "NASA Global Mosaic" <br> * Group: "Base Map" <br> * URL: "http://wms.jpl.nasa.gov/wms.cgi?" <br>'''<br>'''  
 +
#
 +
==== <span class="Apple-style-span" style="font-size: 13px; font-weight: normal; ">.Your project should look like this</span> ====
 +
[[Image:Screen NASA global mosaic.jpg|center|640px|Screen NASA global mosaic.jpg]]<br>
  
#Zoom in to your Project Area using the [[:Category:Zooming Tools|'''Zooming Tools.''']]. '''Please note:''' It's convenient to keep the project area as small as possible, to make the soils download faster<br>  
+
==== <br> ====
#Select the “Soils” layer.<br>[[Image:Layer soils.png|center|Locate and pan over your planning area]]<br>
+
#Click on the “WFS” tool to connect to the soil survey [[Image:LocateArea 9.jpg|Locate and pan over your planning area]] <br>
+
#In the Importing window, click on the star button to see which servers are available.[[Image:LocateArea 10.jpg|Locate and pan over your planning area]] Now, select “NRCS Soils WGS84 Geographic”.[[Image:LocateArea 11.jpg|center|Locate and pan over your planning area]] <br>
+
#The “Layer” dropdown menu shows which layers in the service are available for download. Select “MapUnitPolyExtended”.<br> [[Image:LocateArea 12.jpg|center|Locate and pan over your planning area]]<br>
+
#In "Unique values field", select "OBJECTID"<br>
+
#Click on “OK” and wait for the download to complete.'''Please note:''' If the downloading bar does not show any progress, it might be due to the WFS server not responding. Cancel your download and try again.<br>
+
#Your project should look like the screen below<br>[[Image:LG AddIma 01.jpg|center|640px|Click here to see it full size]]
+
  
<br>
+
=== Related Articles  ===
  
----
+
*[[Create a WMS layer (Web Map Server)|Add a WMS layer]]  
 
+
*[[Save WMS image|Save a WMS image to use it offline]]<br>  
=== Exercise 03 - Importing Imagery <br>  ===
+
*[[WMS data Sources|Available WMS data Sources]]<br>
 
+
To import imagery into GeoAgro GIS it has two requirements:
+
 
+
*GeoAgro GIS supports images in Geographic Coordinates. If you have imagerey projected in other systems, you will need to reproject it, either doing it yourself ('''[[Reproject images to use in GeoAgro GIS|see how]]'''), or asking GeoAgro for help.
+
*GeoAgro GIS supports images in [[Images supported by Geoagro GIS|these formats]].&nbsp;{{Note|when reviewing [[Images supported by Geoagro GIS|supported imagery formats]], please note that depending on the type of image format, it may require to have an additional file with georeferencing information (called 'world file')}}
+
 
+
<br>
+
 
+
==== Importing imagery in Geographic coordinates<br>  ====
+
 
+
In this exercise we are going to import a sample image:<br>
+
 
+
#Download a sample image from [http://geoagro.com/downloads/sampledata/iowa/hardin/NAIP_Orthophoto.zip this link]&nbsp;(8Mb) and save it to your local disk<br>'''Please Note:''' The file is a zip file, to import the image you should unzip it first
+
#Select '''Add new layer''' [[Image:GIS gis Edit 01 01.jpg|Image:GIS_gis_Edit_01_01.jpg]]&nbsp;tool from the '''Edition panel'''<br>
+
#Choose the '''Image layer''' option.<br>[[Image:GIS gis Edit 01b 01.jpg|center|Image:GIS_gis_Edit_01b_01.jpg]]<br>
+
#Fill the fields as below.<br>[[Image:LG cnmp ad 01.png|center|Image:LG_cnmp_ad_01.png]]<br>
+
#Search in your local disk and select the previously downloaded and unzipped image.
+
#Now there's a new Layer in the References Panel named "NAIP Orthophoto" under the "Base Map" group.By default, image layers are turned off at import time, please turn it on by clicking the '''eye icon'''. The map should look like the one below.<br>[[Image:LG cnmp ad 02.jpg|center|640px|Click here to see it full size]]
+
 
+
<br>  
+
 
+
==== Related Articles  ====
+
 
+
*[[Create Image Layer|Add image layer]]
+
*[[Images supported by Geoagro GIS|Types of images supported by GeoAgro GIS]]
+
 
+
==== Importing imagery in Projected systems  ====
+
 
+
If you have imagery available which is already projected in a State Plane Coordinate System, you will need to reproject it to Geographic coordinates:
+
 
+
*[[Reproject images to use in GeoAgro GIS|Reproject images&nbsp;for use in GeoAgro&nbsp;GIS]]<br>
+
 
+
----
+
 
+
=== Exercise 04 - Importing Vector data - shapefile format<br>  ===
+
 
+
<br> In this exercise we are going to import a sample Watershed boundary layer in shapefile format.
+
 
+
#Download sample data to your disk from this [http://geoagro.com/downloads/sampledata/iowa/hardin/wbdhu12_a_mbr.zip '''link'''], and unzip it to an appropiate folder.
+
#From '''Tools for importing data'''&nbsp;select the '''[[Import Layer|Import Layer]]'''&nbsp;tool.<br>[[Image:GIS gis Edit 07a 01.jpg|center|Image:GIS_gis_Edit_07a_01.jpg]]<br>
+
#Click on '''Browse''' &nbsp;and select the recently downloaded shape file. Please fill the remaning fields as described below:<br>'''Group''': 'Base Map'<br>'''Structure''': GeoAgro GIS automatically matches it to the available structure: 'Watershed Boundary'<br>When a shapefile is imported, GeoAgro GIS reads the current projection information, and reprojects it to a geographic coordinate system WGS84.<br><br>[[Image:LG cnmp ad 03.jpg|center|640px|LG cnmp ad 03.jpg]]<br>
+
#After importing, you'll notice that a new layer "wbdhu12_a_mbr" has been created in the '''References Panel,'''&nbsp;with its corresponding polygons in the map area.[[Image:LG cnmp ad 04.png|center|Image:LG_cnmp_ad_04.png]]<br>
+
 
+
==== '''Related articles'''<br> ====
+
  
*[[Import Layer|Import layer]]
+
{{Warning|WMS layers availability depends on external servers. This means that there may be times when WMS layers are not available}}<br>
*[[Structures Management|Structures management]]
+

Revision as of 08:42, 2 August 2011

This exercise is included in the tutorial: Setting up your farm or land project
 One of the first steps in your farm/land project is to access background imagery.

Online Imagery is available as a 'WMS Service'. WMS stands for Web Map Service - a standard protocol for serving georeferenced map images over the Internet that are generated by a map server using data from a GIS database.  Please visit this WMS Article for more information.


Start a project in Iowa

First, create a sample project using the State of Iowa dataset, as detailed in this tutorial


Accessing available Imagery 


  1. Double Click on the 'States' layer to see a full view of the State
    Iowa

  2. Zoom in to the lower left corner of Hardin County
    Iowa

  3. Click on the 'VE Imagery' Layer to turn on Imagery from Bing Maps®. If it doesn't refresh, use the Pan tool Image:GIS_gis_Navi_02_01.jpg to move the view a bit, and refresh the imagery.You should now see aerial imagery from Bing Maps®
    Iowa Bing Maps®

You can, alternatively, use the 'Imagery - NAIP' Layer from the USDA National Aerial Imagery Program (NAIP) and 'Imagery - EDRG' layer to see the available Topography scanned sheets (EDRGs or Digital Raster Graphics). There are still issues in connecting with these sources so you may or may not see it depending on the location you are working on.


Turning on layer 'Imagery - NAIP':

Adding imagery 02.jpg

Turning on layer 'Imagery - EDRG' (Digital Raster Graphics - Topography layer) :

Adding imagery 03.jpg


Saving your imagery to work offline

It's very important to be able to work with imagery offline. Once you have selected your project area, it's a good idea to save the imagery (aerials, topo or other) as offline layers, which will provide faster performance, or the ability to work disconnected from the internet from the field or other disconnected locations.

For this purpose you can follow the steps in this article: Save the WMS image to use it offline

Save WMS image

Accessing Imagery available from other WMS Sources

This option will be useful as more imagery become publicly available on the internet as a WMS service. These may be provided by government or private organizations. A list of WMS Sources that you may use in GeoAgro GIS is available here.

  1. On the right panel, click on the Create New Layer option Image:GIS_gis_Edit_01_01.jpg. Add a WMS Layer, by following  these instructions. We are going to add an example of low resolution image available from NASA. Enter the following values:

    * Name: "NASA Global Mosaic"
    * Group: "Base Map"
    * URL: "http://wms.jpl.nasa.gov/wms.cgi?"

.Your project should look like this

Screen NASA global mosaic.jpg


Related Articles

Warning Warning: WMS layers availability depends on external servers. This means that there may be times when WMS layers are not available