Satellite image processing to provide Digital Elevation Model and Contour Line (2022)

Satellite image processing to provide Digital Elevation Model and Contour Line (2022)

Given the challenges and complexities of various mapping methods over large geographical areas required for applications in water resource management, agriculture, environment, regional studies, etc., satellite images today offer diverse spectral and geometric information, suitable and extensive coverage, availability of data over different and consecutive times, and accessibility. These features provide excellent capabilities for designing data processing models and obtaining essential baseline information for various studies.

In this project, radar and optical remote sensing images were used to extract contour lines (topography) at a scale greater than 1:10,000. The designed method utilized a combination of satellite images and consisted of three main components for generating contour lines:

• Field Operations: In this section, the area was gridded, and control points were designed with GPS in each part of the grid. These points were used both as control points and were added to the digital elevation model to enhance accuracy.
• Interferometry Technique: Using remote sensing interferometry, a Digital Elevation Model (DEM) of the area was produced, from which elevation points were extracted.
• Integration of Techniques: In the third section, various techniques, including NETWORKING, were employed to apply Ground Control Points (GCP) to the points extracted from the digital elevation model. This integration aimed to improve the accuracy of the final product.

Finally, after conducting accuracy assessments and validation of the resulting product, the contour lines of the entire northern coastline of Iran, approximately 800 kilometers long and 10 kilometers wide, were produced.