Frequently Asked Question
1. Introduction
EomQS is a QGIS plugin developed by EODC for access to raw data satellite imagery using a remote desktop connection. Refer to the guide for more information on remote desktop connections: How to access a Virtual Machine with Remote Desktop?
This tutorial will show how to load background data & how to load L1C data provided by EODC.
2. eomQS usage
eomQS is a QGIS Plugin that uses the EODC metadatabase for performing searches and finding L1C data.
After establishing a remote connection, you may find QGIS on the desktop.
For easier orientation the OpenLayers plugin can be used to load a background map. This option is found under the Web menu. Google Maps, OpenStreetMap and other map sources are available to be loaded.
Standard QGIS functions can be used to navigate the map (Zoom in, Zoom Out, Pan etc.). For this demo focus will be on Vienna.
EomQS will open in a new window by clicking on the button highlighted below
The search Tab shows the main parameters for searching the metadatabase.
- Keywords - can be used to search between different keywords, such as satellites (Sentinel-1, Sentinel-1A, Sentinel-2 ...), Sensor modes (IW, EW ...), Product types (GRD, SLC). A list of possible keywords can be found by clicking on the "?" button. Many keywords can be specified, separated by a comma (Sentinel-1, GRD, HR).
- Date, From , To - To enable setting dates, click the Specify Date checkbox. With this selection it is possible to request data only from a certain period
- A bounding box can be set in the Xmax, Ymax, Xmin, Ymin fields. The values can be set manually, globally or through the given map extent.
- Xmin - Xmax: East-West or Longitude
- Ymin - Ymax: South-North or Latitude
After all parameters are input in the query, click the Search button to perform the search. The results are shown in the Results tab
In the section Analyse Results, the results of the query will appear.
A single click on a dataset will show the bounding box of the dataset overlaid over the main QGIS window. Double clicking a dataset will open a new dialog with metadata and a preview image.
When a dataset is highlighted it is possible to load the selected image into QGIS. In the dropdown menu a list of all bands is shown. When a band is selected it is possible to load it by clicking the Load Image button. In this case the True Color Image is loaded.