Inkjet printing is adapted for many digital imaging systems including graphical, industrial and advanced manufacturing applications. Reliability was identified to be one of the key challenges for inkjet printheads due to their susceptibility to variations in temperature, ink consistency, debris or external vibration. Hence, lengthy tests with printouts on kilometers of papers are necessary to establish a measure of reliability, which is time-consuming and extends the development cycle for a given application. In this contribution a line-scan camera is used to observe all droplets from a printhead row in flight at full jetting frequency. This allows for the identification of missing droplets as a function of the printed image, external disturbances as well as the drive waveforms used and other print parameters. This provides a quantitative measurement not only of reliability but also of deviations in droplet velocity and trajectory in a laboratory environment. The paper discusses the necessary hard- and software approaches and details the necessity for various image transformations due to the challenges imposed by the illumination. Furthermore, we will present experimental data as well as speed benchmarks.