IMPROVEMENT OF STIV FOR VIDEO IMAGES CAPTURED UNDER DETERIORATED MEASUREMENT CONDITIONS

Abstract

 The space-time image velocimetry (STIV) technique is one of the image-based techniques for measuring river flow rate using video images. However, there are cases where adequate measurement accuracy is difficult to maintain depending on the shooting conditions of the river surface, and robustness has been required as a measurement system. In this research, we classified factors that cause measurement errors into ten types and developed image filters mainly based wavenumber-frequency spectrum to improve the texture quality of STI. It was made clear that quality of STI can be remarkably improved with the filters and contribute to the robustness improvement of the measurement technique.