Research Developments of Close Range Photogrammetry and Its Application in Particle Tracking

Close range photogrammetry is a branch of photogrammetry and remote sensing，it is a technology that can edit and measure multiple images obtained from photogrammetry within 100m, and will determine its shape, geometric location and size. With the development of technology, the application field of close range photogrammetry technology has been widely used. It has transitioned from ordinary film processing into digital recording and storage of images. The recorded data is directly connected with the computer to improve its operation efficiency, shorten the information processing cycle and realize the full digital process. This paper introduces the research progress of domestic and foreign scholars at different stages from the perspective of calibration method comparison, 3d reconstruction, matching algorithm and application. After comparing and analyzing the advantages and disadvantages of traditional calibration, active visual calibration and self-calibration in detail. Finally, combining with the research field of particle tracking which the author focuses on, it introduces the current bedform measurement system constructed in the experiment and some existing results after preliminary calibration. In addition, due to external factors such as camera accuracy, calibration method, lack of sediment surface texture in the model and fluctuation of water flow, the current river model topographic measurement of binocular stereo vision is still in the exploration stage.