Due to the complexity of the coastal environments, littoral observations should be as comprehensive as possible. In the frame of this study, a site high-frequency, high-resolution Video Monitoring System (VMS) has been installed on a macrotidal range (tidal amplitude > 4 m) sandy beach of Quanzhou coast (China). This article proposed the use of Timestack derived from video imagery to extract the waterline oscillation caused by the wave runup process, and to further reconstruct the terrain of the intertidal beach at the timescale of tidal cycle coupled with the tide level. During a field experiment in January 2022, more than 1800 individual wave runup events were captured. Linear regression between video detected extreme runup level and those estimated with in situ measurement (R_max and R_2%) showed a correlation coefficient of r²=0.834 and r²=0.921, respectively. The reproduction of the intertidal beach digital elevation model (DEM) is satisfactory, verified by RTK-GPS with an averaged vertical RMSE = 0.134 m. Our results demonstrate that video monitoring is an effective tool using for the investigation of coastal hydrodynamic and geomorphic processes.