The pebble flow characteristics of free and rate-controlled drainage in the mono-layer pebble bed formed in the two-dimensional (2D) silo are of vital importance, which contributes to revealing the rules of three-dimensional (3D) pebble flow a lot. Tracing all particles in the bed is still difficult although tracing several particles is feasible in current published literatures. In the research, we constructed the PTV platform containing a Monolayer-Pebble-Bed with Adjustable-Configurations (MPBAC). The PTV platform of MPBAC shoots the whole process of free and rate-control drainage with highspeed cameras, then the images of particles are preprocessed and recognized and the position of every particle in every picture is obtained. After that, the particle matching and amending methods are carried out, having taken the misidentified particles and missing particles into consideration. With every single particle’s position known, the average velocity and the residual time distribution (RTD) of every single particle can be gained eventually. Many issues, e.g., the flow pattern, the regime of pebble flow and the velocity field can be studied and analyzed. It turns out that an average accuracy of 99% for recognition and 98% for tracing can be expected in more than 95% of cases, proving that the current PTV platform of MPBAC with the postprocessing program is definitely sufficient for the future researches about the monolayer pebble bed.