Archive Imagery: Navigating the Search Platform

Introduction

In this tutorial we’ll be showing you how to successfully navigate and use the Geostack search platform to find satellite imagery.

The search platform is the place where you can begin your imagery order experience. Click on the “Explore Exisiting Images” option on the welcome window or select the Archive tab at the top of the left-hand side bar. Now that you have selected the archive platform, let’s cover a few important features.

What you’ll need:
Access to the Arlula API account signup page.

Now that you have selected the Archive platform, let’s cover a few important features. 

To search for imagery, you will first need to select a date or date range and an Area of Interest (AOI).

Selecting a Date

To choose your desired date or time period click in the first search bar on the left hand side of the search platform. By default, the platform displays two months prior to and one month after the day of your search. A calendar will appear when you click in that space, allowing you to easily select your desired date or time period or use the prompts to the right of the calendar to automatically select date ranges a week, a fortnight, a month, three months, and 6 months before your search day. Alternatively, you can enter the date or time period manually by typing directly in the search bar using a year/month/day format. Note: Archive imagery can only be acquired from dates in the past. 

Selecting an AOI

To select an AOI you have several options: 

  1. You can use the second search bar on the left hand side of the page, below the date range, to add coordinates, an address, or general location.
  2. To the right hand side of the page, is a toolbar to aid your search: 
    1. The Marker Tool can be used to place a pin at your designated point
    2. The Bounding Box Tool allows you to select a square area by clicking a point and then dragging to desired area size. The tool displays total square kilometres that are selected at the top of the selection area. 
    3. If you have an irregularly shaped AOI, the Polygon Tool can be used to select an area using different points. Like above, the tool displays total square kilometres for the selected area. 
    4. If you have a KML, WKT or GeoJSON file containing one or more polygons, you can use the File Upload Tool to select your AOI. The “File Selection” window will pop up to upload the file. Once the file is uploaded, click select in the bottom right corner. 
    5. If you would like to restart your AOI selection, click the bin icon at the bottom of the tool bar. This will remove any pin or selection area. 
  3. Once the AOI is selected or entered, specify the desired resolution (Very High, High, Medium, Low, All)  by clicking the corresponding button. 
  4. When ready to launch the search, click the purple See Options button located at the bottom of the left hand side bar.

Advanced Search

To further refine your search, you can access the advanced search settings by clicking on the Advanced Options drop down below the resolution search. Here, you can select desired supplier, off-nadir, and cloud coverage. By choosing your desired settings with these filters, you can optimise your search results to meet your specific requirements.  Once you have selected your desired settings, click the purple See Options button located at the bottom of the left hand side bar to launch the search.

Evaluating Search Results

After you run your search, the results will be presented in the left-hand sidebar. You can easily scroll through to see what images match your desired criteria. Each result will include valuable information: the date of image capture, the scene reference, the source,  the resolution/GSD, the number of bands, the estimated delivery time if the imagery is ordered and  the base price for the area of the scene to be delivered.

To view more information about the scene, select the arrow to the right of the scene information. This will open the  More Information window. Here, you will find the supplier, the scene reference,  the off nadir angle, the scene and order area within the scene, cloud cover of the whole scene and the available bands.

To view a sample of the scene on the map, select “Show on Map”, below the thumbnail. This will display a low resolution version of the scene on the map. This can be helpful for identifying if the required portion of the scene is obscured by cloud cover.

Sorting Search Results

If you would like to arrange your search results, click Sort By in the top left corner of the results. You can sort the results by Price, Capture Date, GSD, Cloud, and Off Nadir. Next to the Sort By Box is the Direction Box. This allows you to modify the sort direction (ascending or descending). To reset any applied sorting preferences and return to the original sort results, click on RESET SORTING at the bottom of the menu list.

Add to Cart

When you are ready to start an order, click on the Add to Cart button in the lower right hand corner of the desired scene result. The Add Scene to Cart window will appear in which you will see the scene details, bundles available, licences available , and the pricing details. Make the bundle and licence selections that are applicable to you through the corresponding drop down menus. Once you have made your selections, review the final pricing details, and click the Add to Cart button in the lower right-hand corner. The imagery will now be available in your cart. To proceed with the order, select the Cart icon in the top right corner of the page. Alternatively, if you would like to add additional imagery you can continue your search on the browser. 

If you have any questions about this specific tutorial or would like to learn more please feel free to contact the Arlula team at hello@arlula.com.