The reasons for the nonuniformity in CCD imaging were researched

and the feasible schemes to correct the nonuniformity of an image from a satellite were discussed by using a flat field correction method. Then

based on FPGA-based processor

a real-time correction approach was presented to control all of the operations of TDICCD to implement the hardware correction of the nonuniformity. Furthermore

the Nonuniformity Equivalent Digital Number (NUEDN) was calculated by using FPGA to extract the first 32 rows of a raw image in the uniform exposure

and the real time correction for digital images was carried out when the NUEDN was set to be more than 2. The experimental results in the uniform exposure indicate that the NUEDN falls to 0.29. Dynamic push-scanning imaging test was also performed with a standard resolution chart attached on a roller

and the results have proved the validity of the approach in practical projects.