Video Analysis of Water Drop Penetration Time Using Temporal Action Localization for Evaluating Soil Water Repellency

We present a system for the automated measurement of Water Drop Penetration Time (WDPT) that is commonly used for evaluating soil water repellency (SWR). Conventional manual measurements of WDPT are labor-intensive, subjective, tend to produce variability of outcomes, and are not available in remote and difficult-to-reach locations. The developed system performs a standardized WDPT test, estimates WDPT, and evaluates SWR. The entire process from drop landing on the soil surface to its complete absorption is modeled as a temporal action, and consequently, the WDPT estimation is solved using Temporal Action Localization (TAL) models. Two state-of-the-art TAL models are explored and compared: ActionFormer and TriDet. Although TriDet has a lower mean absolute error for fast absorption events, ActionFormer outperforms it by the average AP metric and the accuracy of SWR characterization.