When viewed in a GIS, imagery is typically transformed or projected to a map coordinate system (MCS) known as map space. When displaying imagery in map space, the image is stretched and twisted to fit accurately to a 2D flat map. This is appropriate in most cases, since imagery is usually captured vertically, as nadir or near-nadir. There are scenarios, however, in which imagery is acquired at an angle in reconnaissance, surveillance, situational awareness applications. When an oblique image is fitted to a 2D map, distortions can be severe, making it difficult to interpret the image (see the first image below). These distortions also make it difficult for image analysts to make precise image measurements, compromising accuracy.
The ArcGIS Image Analyst extension for ArcGIS Pro allows you to work with oblique imagery in its native geometry (image space) rather than in map space. This eliminates the distortion or visual artifacts caused by reprojection, orthorectification, or other geometric transformations. The perspective mode of the map view displays oblique imagery in an image coordinate system (ICS). In this mode, imagery is viewed from the sensor's perspective in the map view, rather than stretched to fit the ground, making it more intuitive to interpret (see the second image above). You can also seamlessly transition between an ICS and MCS to display, interpret, collect, and edit GIS feature data on the oblique imagery.
Explore the following resources to get started visualizing and exploiting imagery in image space using ArcGIS Pro. (Not sure where to start? Look for the star by Esri's most helpful resources.)
Note:
To visualize imagery in image space, you need ArcGIS Pro 2.1 or later with the ArcGIS Image Analyst extension.Imagery Workflows resources
Review the community-supported tools and best practices for working with and automating imagery and remote sensing workflows:
- Try exploiting imagery in image space in ArcGIS Pro by following the ArcGIS Image Analyst tutorial - image coordinate space.*
ArcGIS help
Review the following links on reference materials for ArcGIS products:
- Read an overview of image space analysis in ArcGIS Pro.
- Learn about mensuration, which works in image space or map space.
ArcGIS blogs, articles, story maps, and technical papers
Review the following supplemental guidance about concepts, software functionality, and workflows:
- Read the Introducing Image Space Analysis blog.
Videos
Review the following Esri-produced videos that clarify and demonstrate concepts, software functionality, and workflows:
- Watch a video showing how to visualize and edit data in image coordinate space (4 minutes).*
- Watch a quick demonstration contrasting image space and map space (1 minute).
- See how stereo and image space in the ArcGIS Image Analyst extension enrich visualization (2 minutes).
Esri Community
Use the online imagery community to connect, collaborate, and share experiences:
- Visit the Esri Imagery and Remote Sensing community to connect, collaborate, and share experiences regarding image space.