ESA’s Heritage Data Visualisation tool, or HEDAVI, which enables the analysis and visualisation of more than 40 years of satellite data, now has exciting new features to help users craft their own Earth observation stories.

The Discover mode in HEDAVI showcases the usefulness of Earth Observation (EO) data in a variety of applications through a list of case-studies—so-called “stories”. The first new feature allows users to share links to the stories in HEDAVI. The second new feature allows them to export any image of a case-study from the Discover mode to the Explorer mode.

In Explorer mode the image can be edited, for instance by adding new data and modifying the visualisation parameters and settings. The edited image can then be saved and shared without modifying the original HEDAVI case-study.

ESA’s HEDAVI tool allows users to visualise and process on-the-fly Heritage and Third Party Missions data. The tool offers the possibility to define a variety of settings to customise the visualisation and the processing steps to be performed on the selected datasets, and finally to share the results with other users.

This article is a step-by-step guide showing how users can create new material starting from existing, previously published case-studies (stories), thanks to two new features in the tool. If you are new to HEDAVI, you can learn about the tool and how to use it in our previous guides.

Sharing a story

A "share button" is now available at the top right of the story window to copy a direct link to the story in the portal.

Opening in Explorer

A case study (or story) is made of a succession of interactive views on a virtual globe, each accompanied by a caption and sometimes a comment. Each view encompasses one or more satellite images with their image processing ordered in a layer stack, a background layer, as well as a point of view. These parameters are saved as a URL similar to a permalink called “hyperlook”.

The stories cannot be edited, but the views can now be opened interactively on the virtual globe in HEDAVI Explorer. An "external link button" is available at the top-right of the story-view window, which will open the view in a new window in the Explorer portal.

Editing the layer stack

These views can then be edited by changing different elements such as the processing of the satellite images, the camera position, the background layer or by adding new layers.

A future tutorial will explore in depth how to manage the layer stack and the hyperlooks, but here is a basic demonstration of this functionality:

Open the layer stack panel via the “layer stack button”, the small button with three superimposed sheets located at the right of the display panel.

In the example below, the style used for the satellite image will be changed from a near-infrared, red, green colour composite to a red, green, blue colour composite.

To change the style, right-click on the selected layer, then open the “Style” menu. Select one of the available styles, or create your own custom style.

The screenshot below shows examples of changes to the hyperlook: the style of the satellite image and the camera position have been modified, the camera view is now set in 3D instead of 2D and the yellow overlay showing the country borders has been swapped for a green one.

Saving and sharing your modifications

If you want to save your changes and return to edit them later, open the hyperlook manager by right-clicking the layer or folder you are editing, and then select the “Share hyperlook” button.

If a hyperlook already exists for the selected folder, open the “Show link” button to copy the link to the hyperlook.

If you want to save your edits and share them in a different hyperlook, use the “Create new and show” button. The URL displayed in this window can be used to access the edited version later. While the original hyperlook is unchanged, the edited view is now saved and you can overwrite it as shown below, or continue editing.

The “Save changes and show” button overwrites the content of the current hyperlook. One can use it on hyperlooks that have been created by the user, while it cannot be used on original hyperlooks.

When this button is used, the address of this hyperlook is shown in a modal window when the operation is successful. Please note, the “Save changes and show” button is different to the “Create new and show” option, which creates a new hyperlook entirely.

With these new features, you can modify existing stories to fit your needs and share both the original story and the edited material.

Go to HEDAVI Discover to adapt existing stories to your needs.