Improving the functionality of tamura directionality on solar images
Azim Ahmadzadeh, Dustin Kempton, Michael A. Schuh, Rafal A. Angryk · 2017
Directionality as a textural parameter is a great tool in many image-based tasks including the automated analysis of medical, geographical, or astronomical images. Tamura directionality is a popular parameters that measures the degree of texture directionality of images. In this study, we review the original idea and also address some ambiguities present in the original definition that play an important role in the effectiveness of this parameter. Then, we propose different ideas to attack each of the addressed ambiguities and find an optimal setting that maximizes the effectiveness of this parameter. Lastly, we evaluate the effect of our modifications on a large collection of solar images captured by the Solar Dynamic Observatory mission. We show that such modifications significantly improve the effectiveness of this parameter. Although, different settings might be obtained for images with different sort of texture, the methodology for finding an optimal setting remains the same regardless. The goal of our study is to make sure that parameters that are being frequently used in several areas, especially in the interdisciplinary research between solar physicists and computer scientists, are calculated accurately and effectively.