A novel computational method for dynamic laser speckle and its application to analyze water activity during photosynthesis in papaya leaf

Abstract

Dynamic Laser Speckle (DLS) images are processed under different computational methods to extract activity map and numerical information of the activity present in the sample. Some existing methods include GD, Fujii, which provides the activity map, and IM, AVD, which numerically quantifies the activity. However, there is hardly a method that simultaneously provides speckle activity map linked with a numerical value. It takes much time to process with different methods for graphical and numerical information about the speckle activity. In this work, a new method has been proposed, which provides the speckle activity map associated with a numerical information for DLS analysis. We have found that both the graphical and numerical results obtained from the proposed method are in good agreement with other existing methods. In another experiment of Biospeckle imaging of papaya leaf subjected under different PAR intensities, we have found that the average frequency (represents the biospeckle activity) of papaya leaf increases as the photosynthesis rate increases. Furthermore, this method takes less computational time (0.70 ± 0.021 s) to process data compared to GD (1.89 ± 0.012 s), Fujii (0.75 ± 0.042 s), and IM & AVD (1.1 ± 0.017 s).