About Planet Basemaps¶
A basemap is a layer containing geographic information that serves as a background. It provides context for additional layers that lay over the top of the basemap.
For example, you can view the basemap containing the physical features of a country and on top of that a layer is added that contains the list of post offices in a nation. The underlying layer provides the location references for post office features. Similarly, you can also add additional features that do not change often. For example, boundaries, rivers, lakes, roads, and highways.
Planet offers a range of Basemap products for different applications and use cases.
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The Global Basemap is used for mapping and visual simulation use cases. It is automatically generated annually, covers the entire globe in RGB bands, and has a visual color curve applied.
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Select Basemaps are best suited for monitoring and analytics-driven use cases, where basemaps enable an understanding of change over time. Select Basemaps are generated in accordance with your needs, allowing choice of source imagery, frequency of updates, and delivery.
Global Basemap¶
Planet's Global Basemap is generated systematically between 74° North and 60° South in order to minimize distortion at the poles, using PlanetScope and/or RapidEye imagery. Planet leverages a proprietary “best scene on top” algorithm that selects the highest quality imagery from our catalog over the normal hemispheric leaf-on periods. This is roughly July to September in the northern hemisphere, and January to March in the southern hemisphere, with year-round imagery in the tropics to create the Global Basemap.
Select Basemaps¶
Planet's Select Basemaps are generated according to a customer-specified area of interest and are composed of PlanetScope imagery (visual or surface reflectance).
Select Basemaps Visual¶
Select Basemaps are generated using a proprietary “best scene on top” algorithm that selects the highest quality imagery from Planet's catalog over a specified time range. By selecting the best images, Planet is able to create radiometrically and spatially accurate, high-resolution basemaps that minimize the effects of cloud, haze, and other image variability.
| Source Imagery | Download (GeoTIFF) Bands | Streaming (WMTS) Bands | Monitoring Frequency | Zoom Level | Color Target |
|---|---|---|---|---|---|
| PlanetScope Visual product | RGB | RGB | Quarterly Monthly Biweekly Weekly |
15, 16 |
MODIS |
Select Basemaps - Surface Reflectance¶
Select Surface Reflectance Basemaps are generated using the Planetscope Surface Reflectance asset type (PSScene4Band analytic_sr) as input. The Select Surface Reflectance product utilizes external sources of data like MODIS for deriving atmospheric parameters. Processing details may be found in the Planet Imagery Specifications document.
| Source Imagery | Download (GeoTIFF) Bands | Streaming (WMTS) Bands | Monitoring Frequency | Zoom Level | Color Target | ||
|---|---|---|---|---|---|---|---|
| PlanetScope Visual product | RGB | RGB | Quarterly Monthly Biweekly Weekly |
15, 16 |
MODIS |
Select Basemaps - Surface Reflectance and Normalized Surface Reflectance¶
| Surface Reflectance Basemap Type | Prioritizes | Data | Pixel Values | Normalization |
|---|---|---|---|---|
| Normalized (normalized_sr) |
Spatial & temporal consistency; training data | 4-band, 16-bit | Modified Surface Reflectance | Landsat 8 Sentinel-2 |
| 8-Band Normalized (8b_normalized_sr) |
Spatial & temporal consistency; training data | 8-band, 16-bit | Modified Surface Reflectance | Sentinel-2 |
| Analytic (analytic_sr) |
Spatial accuracy; precise spectral responses | 4-band, 16-bit | Surface Reflectance | None |
Availability¶
| Surface Reflectance Basemap Type | Prioritizes | Data | Pixel Values | Normalization |
|---|---|---|---|---|
| Normalized (normalized_sr) |
Spatial & temporal consistency; training data | 4-band, 16-bit | Modified Surface Reflectance | Landsat 8 Sentinel-2 |
| 8-Band Normalized (8b_normalized_sr) |
Spatial & temporal consistency; training data | 8-band, 16-bit | Modified Surface Reflectance | Sentinel-2 |
| Analytic (analytic_sr) |
Spatial accuracy; precise spectral responses | 4-band, 16-bit | Surface Reflectance | None |
Basemaps Product Specifications¶
Basemap Quads¶
The imagery within Planet Basemaps is distributed as a grid of GeoTIFF files, which are called “basemap quads” or simply “quads.” The size of each quad is 4096 X 4096 pixels.
| Attribute | Description |
|---|---|
| Imagery | PlanetScope and RapidEye (Visual) PlanetScope (Surface Reflectance) |
| Pixel Size (resolution) Note: The precise pixel size in meters may be roughly calculated with this formula: Pixel Size at the Equator x cos(latitude). | 4.77 m at the Equator for zoom level 15 (PlanetScope and RapidEye) 2.39 m at the Equator for zoom level 16 (PlanetScope and RapidEye) 0.597 m at the Equator for zoom level 18 (SkySat) |
| Image Bit Depth | 8 bits per pixel (Visual) 16 bits per pixel (Surface Reflectance) |
| Bands | Red, Green, Blue, Alpha (Visual) Blue, Green, Red, NIR, Alpha (Surface Reflectance) Coastal Blue, Blue, Green I, Green II, Yellow, Red, Red Edge, NIR, Alpha (8 band) |
| Projection | WGS84 Web Mercator (EPSG:3857) |
| Size | 4096 x 4096 pixels |
| Processing | Atmospheric correction (Select Surface Reflectance Basemaps only). May be radiometrically balanced.Seam Lines may be minimized with tonal balancing. Geometrically aligned. |
Planet Basemaps Delivery¶
There are multiple ways to download Basemaps quads as described below.
Basemaps Viewer¶
Basemaps Viewer is an online tool used to view and download basemaps.
Basemaps API¶
The Basemaps API is Planet's interface for working with Planet's Basemaps products. The detailed reference Planet Mosaics API 1.0 contains various endpoints that allow developers to create scalable workflows. Basemaps API download URLs can be also used as direct COG links without the need to download, which can be steamed.
Some use-cases of the Basemaps API are:
- Find the quads that intersect an Area of Interest and download those quads.
- Get the list of items that contribute to the particular quad.
- Stream into web applications using the XYZ and WMTS protocols.
- Get a list of series and mosaics available for a user.
Planet offer additional use cases. For more information, refer to the API documentation and the following resources.
- Quad Example: A quad example provided by the Planet Engineering team.
- Planet University: How to Download Basemaps Using the Basemaps API
- CLI: A command line version of code to find and download quads for specific mosaics and Areas of Interest.
Orders API¶
Refer to Ordering Basemaps using the Orders API.