Our Products/Services
GIS Accuracy is our number one product: Through GCPs, Data Collection and Post-Processing

GIS technology has changed the world. Populations have come to expect to be able to find anything, anywhere, any time, and yet the planet is a very big place. While scientists have learned how to derive imagery from satellites and even LiDAR, all of that spatial data needs to be grounded.

CompassData's specialty is providing timely, accurate, consistent Ground Control Points (GCPs) that are designed to bring maps and GIS data into focus.

We do this through continually adding to our Ground Control Point archive, which is now the world's largest commercially available Ground Control data set, with more than 18,000 GCPs available right now for immediate download.

In our mission to Map the World, we have field collection crews all over planet earth, and so if we do not have a GCP you need, we can plan a field data collection project specifically for you, utilizing outstanding professionals in a fast-turnaround, with consistent results every time.

We can post-process the data for you as well.

We provide analysis of LiDAR imagery, using our extensive experience and GCP archive to ensure its accuracy.

In short, CompassData can provide any need you may have for precise control in mapping, GIS data processing or any other spatial application.

CompassData Ground Control Accuracy

CDI offers five levels of data collection to meet client needs. Sub-meter accuracy offers little help to a 30-cm resolution digital orthophoto project; in the same fashion, Centimeter accuracy ground control is drastic overkill for 0.25 meter satellite image support. We offer full consulting services to aid our clients in determining the accuracy standard and collection density for any given project.

An accuracy assessment is provided as part of our standard deliverables to demonstrate the horizontal and vertical accuracies for each point we collect. As we continue our collection processes with better equipment and more robust satellite constellations, we expect our accuracy levels to increase as a result.

 

 

 

 

 

CompassData Collection Methodology:

In order to maintain consistent levels of accuracy and quality in our coordinate sets, we test both our data and our data collection procedures against known positions in the world to assess the overall accuracy of a given collection.

This allows us to provide supporting documentation that demonstrates our measured coordinate values against the stated coordinates for a higher-order benchmark.

To do this, we collect both the customer-specified points, and a published National Geodetic Survey or International GNSS Service benchmark within or near the project area with a dual-frequency receivers, using the same collection procedures for GCPs and the NGS/IGS benchmark.

Once collected, all points are post-processed to determine the final coordinates of the GCPs as well as the observed NGS or IGS point. The delta, or difference, between our measured coordinate value and the published benchmark coordinate value is then evaluated to determine the measurement accuracy of the GCPs.

The professionals at CompassData match the appropriate GPS equipment and process methodology to the clients' desired precision levels.

As GPS technology increases, and the constellation of GPS-capable satellites grows, inherent collection accuracies can only increase, providing a significant benefit to the spatial data user community.