Clickto load an exemplary time series of Landsat and RapidEye observations.
Open the sensor paneland change the sensor names
Default Changed email@example.com Landsat firstname.lastname@example.org RapidEye3
The change of sensor names becomes visible in other other parts of the GUI as well, e.g. the list of time series source images.
- Use the scroll band and the map tools to change the temporal and spatial subset shown from the time series.
- Open the Mapping panel, change the map view name from Map View 1 to True Color and set the multiband color render band selection to RGB = 3-2-1 for both, Landsat and RapidEye images (right-click on layer, ).
Now we like to optimize the color stretch. Choose a -clouded Landsat observation like 2014-06-24 and use the map context menu (right-mouse-click) to click on. Repeat with Linear and Gaussian stretch as well as for RapidEye images to see how this changes the band-specific min/max values in the Map View settings.
Expand the Map Properties combobox (in the Mapping panel), increase the map size to 300x300 pixel and press Apply.
Go back to the 2D plot page and add a second profile with RapidEye data as Sensor source. Change the expression field to show the Normalized Difference Vegetation Index (NDVI) for both sensors:
Sensor Expression NDVI Landsat (b4-b3)/(b4+b3) RapidEye (b5-b3)/(b5+b3)
The Graphical User Interface¶
Just like in QGIS, many parts of the GUI are adjustable panels. You can arrange them as tabbed, stacked or separate windows. Activate/Deactivate panels under
This window lists the individual input raster files of the time series.
- Date corresponds to the image acquisition date as automatically derived by the EO TSV from the file name. Checking or unchecking the box in the date field will include or exclude the respective image from the display
- Sensor shows the name of the sensor as defined in the Sensors / Products tab
- ns: number of samples (pixels in x direction)
- nl: number of lines (pixels in y direction)
- nb: number of bands
- image: path to the raster file
You can add new rasters to the time series by clicking Add image to time series. Remove them by selecting the desired rows in the table (click on the row number) and pressing the Remove image from time series button.
If you have your time series available as one large raster stack, you can import this file via
Clickto load a small example time series.
Sensors / Products¶
The EO Time Series Viewer automatically assesses different characteristics of the input images (number of bands, geometric resolution etc.) and combines identical ones into sensor groups (or products). Those are listed as follows in the Sensor / Products window:
nameis automatically generated from the resolution and number of bands (e.g. email@example.com). This field is adjustable, i.e. you can change the name by double-clicking into the field. The here defined name will be also displayed in the Map View and the Time Series table.
nb: number of bands
n images: number of images within the time series attributed to the according sensor
wl: comma separated string of the (center) wavelength of every band and [unit]
id: string identifying number of bands, geometric resolution and wavelengths (primary for internal use)
Only after Identify Pixels and Features is activated you can select the other identify tools (, , ). You can activate them all at once as well as of them, in case of the latter variant clicking in the map has no direct effect (other than moving the crosshair, when activated)
In the map properties box you can specify Width and Height, as well as background Color and the CRS of the single map canvases. Click Apply to apply changes. By default the keep ratio option is checked, i.e. height will be the same as width. In case you want to have unequally sized views, deactivate this option.
A map view is a row of map canvases that show the time series images of different sensors/product in the same band combination, e.g. as “True Color bands”. The map view panel allows to add or remove map views and to specifiy how the images of each sensor are to be rendered.
- You can add new Map Views using the button. This will create a new row of map canvases. Remove a map view with the button.
- In case the Map View does not refresh correctly, you can ‘force’ the refresh using the button (which will also apply all the render settings).
- Access the settings for individual Map Views by clicking in the mapview
- You can use the button to highlight the current Map View selected in the dropdown menu (respective image chips will show red margin for a few seconds).
For every Map View you can alter the following settings:
- Hide/Unhide the Map View via the Toggle visibility of this map view button.
- Activate/Deactivate Crosshair via the Show/hide a crosshair button. Press the arrow button next to it to enter the Crosshair specifications , where you can customize e.g. color, opacity, thickness, size and further options.
- You may rename the Map View by altering the text in the Name field.
Similar to QGIS you can change the visual representation of raster or vector layers in the layer properties. To open them, right-click on the layer you want to alter and select
Cursor Location Values¶
This tools lets you inspect the values of a layer or multiple layers at the location where you click in the map view. To select a location (e.g. pixel or feature) use the Select Cursor Location button and click somewhere in the map view.
The Cursor Location Value panel should open automatically and list the information for a selected location. The layers will be listed in the order they appear in the Map View. In case you do not see the panel, you can open it via.
By default, raster layer information will only be shown for the bands which are mapped to RGB. If you want to view all bands, change the Visible setting to All (right dropdown menu). Also, the first information is always the pixel coordinate (column, row).
You can select whether location information should be gathered for All layers or only the Top layer. You can further define whether you want to consider Raster and Vector layers, or Vector only and Raster only, respectively.
Coordinates of the selected location are shown in the x and y fields. You may change the coordinate system of the displayed coordinates via the Select CRS button (e.g. for switching to lat/long coordinates).
The Temporal Profiles panel lets you visualize temporal profiles. On the left side you can switch between the profile and the coordinates page. The latter lists all coordinates of selected or imported profile locations.
- Adding and managing a temporal profile:
Use to create an additional plot layer, and double-click in the Coordinate field in order to select the desired location (so e.g. the newly chosen pixel) or just change the location in the current plot layer.
Similarly, you can change the sensor to be visualized by double-clicking inside the Sensor field and choosing from the dropdown.
Click inside the Style field to change the visual representation of your time series in the plot.
The DN or Index field depicts which values will be plotted.
Here you may select single bands (e.g.
b1for the first band)
or you can calculate indices on-the-fly: e.g. for the Landsat images in the example dataset the expression
(b4-b3)/(b4+b3)would return the NDVI.
You can also move the map views to a desired date from the plot directly by right-click into plot
- Importing or exporting locations:
The spectral library view allows you to visualize, label and export spectral profiles.
- Use the Select a spectrum from a map button to extract and visualize a pixels profile (by clicking on a pixel on the map).
- You can add a selected spectrum to your spectral library by clicking on .
- The gathered spectra are listed in the table on the right. For every spectrum additional metadata will be stored, e.g. the date, day of year and sensor.
- When the button is activated, the profile will be directly added to the library after clicking on a pixel.
- Change the display style (color, shape, linetype) in the Spectral Library Properties, which can be accessed via the button in the lower right.
- The spectral library table behaves quite similar to the attribute table you know from QGIS:
- You can edit the content by entering the editing mode
- You can add further information by adding fields via the button (e.g. different class labels). Remove them with , accordingly.
- Double-click into a desired field to change its content
- Remove spectra by selecting the desired row(s) in the table and click
The EO Time Series Viewer assists you in describing, i.e. label, reference data, e.g. to describe at the occurence of land cover types and events. Whether your locations (point, lines or polygons) of interest already exist, or are being digitized in the visualized maps first, in both cases you want to describe them in the attribute table of the vector layer.
The EO Time Series Viewer supports this with “Quick Label” short-cuts from the map context menu. If triggered, they send temporal or categorical information direct to the attribute cells of selected geometries, e.g a polygon that has been selected in a map.
Let’s assume we have a map related to a Landsat (LND) observation taken at 2019-02-05T11:23:42.00. The following table shows how this is translated into linked vector fields:
|Type of linked vector layer field|
|Day of Year (DOY)||36||36||36|
To use Quick Labels, open the vector layer properties and activate them in the Attribute Form widget: