Time delay and integration (TDI) is a technology used in line-scan cameras to improve moving image quality. As an image sweeps over the sensor array, the pixels collect charge; at certain intervals the charge in the wells in each of the rows is moved to the adjacent rows, in the same direction and velocity as the moving image. TDI sensors help provide high quality and contrast images even under low illumination providing the image speed is same as the speed of the charge movement. In this paper we model the TDI process by treating it as a discrete time sampler and, using this model, we develop several simple algorithms that are able to self-synchronize the TDI row charge movement based solely on the output of the TDI sensor itself rather than on an external encoder. The algorithms are simple enough to be implemented on a small size FPGA.