A spectral optical flow method for determining velocities from digital imagery

Area of Science:

• Solar physics
• Fluid dynamics
• Image analysis

Background:

• Understanding solar surface flows is crucial for heliophysics.
• Existing methods for analyzing solar images can be complex and require significant preprocessing.

Purpose of the Study:

• To introduce and validate a novel method for determining solar surface flows.
• To assess the performance of the optical flow technique across various solar imagers.
• To compare the new method with established techniques for accuracy and efficiency.

Main Methods:

• Application of optical flow techniques (opflow3d procedure) to solar image datasets.
• Testing with perfect test data to establish baseline accuracy.
• Validation against a distinct, established method using high-resolution solar images.

Main Results:

• The opflow3d procedure accurately estimates velocities from solar images.
• The method produces results consistent with other techniques on global scales.
• Comparable results were achieved with a high-resolution dataset without image tuning or filtering.

Conclusions:

• The presented optical flow method is a robust and efficient tool for solar surface flow analysis.
• It offers accurate velocity measurements comparable to established methods.
• The technique's ability to work without preprocessing simplifies its application in solar physics research.