Optical monitoring systems have become essential tools for measuring hydrodynamic parameters in the shoreface zone. They offer continuous data collection over large spatial areas, making them highly valuable in coastal research. However, accurately estimating wave heights from optical imagery remains a challenge due to the complexities of wave interactions, variations in camera configurations, and environmental conditions. This study evaluates two methodologies for estimating wave heights in the non-breaking zone using UAV footage, building on the limitations of previous techniques. The methods automatically detect waves using image processing techniques, initially measured in pixels. These pixel-based measurements are then converted to real-world coordinates (meters) through geometric transformations. A central focus was the variability of wave height estimates across different regions of interest (ROIs) of the image. The findings emphasize the critical role of optimal camera placement in enhancing measurement accuracy. This analysis contributes to advancing optical monitoring techniques, improving hydrodynamic parameter estimation, and better understanding dynamic coastal environments.