Maps Engine

Starting with your source data

Your source files can contain raster imagery, vector data, or KML markup. All can be used with both Google Maps and Google Earth. When a file of source data is uploaded into the Google Maps Engine catalog, it appears in the Google Maps Engine catalog under Data sources.

Projections

You can upload raster files in any projection that complies with Geospatial Data Abstraction Library (GDAL). You'll need a PRJ file if your source format requires projection information and does not have it embedded.

Data types

Imagery, a type of raster data, consists of a grid of cells that cover an area of interest. Each pixel, the smallest unit of information in the grid, displays a unique attribute and can be mapped to latitude/longitude values. Imagery data is typically acquired by satellites or aerial cameras.

A mosaic contains a number of separate, small images that you can manage as a single entity. The contiguous sections are joined without masking and feathering.

Vector data consists of the following types of geographic features:

• Geographic coordinates (points), or collections of points (multi-points)
• Sequences of connected geographic coordinates (lines), or collections of lines (multi-lines)
• Closed sequences of geographic coordinates (polygons), or collections of polygons (multi-polygons)

Each feature typically has attribute fields, such as name, street address, or website URL. In the process of uploading and processing a vector data source, Maps Engine converts it into a format called a vector table.

KML data sources consist of one or more Keyhole Markup Language (KML) files that's uploaded as it is or compressed in a KMZ file. KML is a file format used to display geographic data in an Earth browser, such as Google Earth, Google Maps, and Google Maps for mobile. KML files can contain both vector data and imagery.

Linked KML is the URL and display name for a Keyhole Markup Language (KML) or zipped KML (KMZ) file. The file must be hosted on an external (not google.com) server. Linked KML files are visible to Google Earth users as if they were layers of a map.

Terrain, like imagery, is a type of raster data that contains topographical and bathymetry information about a geographic area. Pixel coordinates in a terrain data file can be mapped to elevation values as well as to latitude and longitude.

Associated sidecar files

Some source file types have associated sidecar files. These help with the interpretation of the main file's contents; for example, they may contain the geographic projection metadata needed to align imagery or vector data with Earth coordinates. Without the appropriate sidecar files, an upload could fail.

Attributions

Every imagery data source needs an attribution that acknowledges the organization that provided the data.

For more information

For information on the types of files you can upload, refer to Supported data formats and limits.