This paper introduces a readout circuit for a frame difference sensor based on the 180-nm CIS process. The data compression feature of the circuit reduces data transmission bandwidth and storage pressure. The advantages and disadvantages of the two data output formats，viz. frame difference and address-event representation，which are used in dynamic vision sensors，are analyzed to design a readout circuit that can adaptively switch between data output modes. This circuit dynamically selects the optimal data compression method based on event density，thereby effectively reducing redundant data. The auto-zeroing technology is employed to reduce the offset voltage in the event encoding circuit. Simulation results show that the auto-zeroing technique reduces the impact of offset voltage on quantization results(from 38. 77 to 1. 185 mV)，thus significantly improving the accuracy and stability of the circuit. Additionally，the frame rate can be dynamically adjusted between 375 and 1627 fps to satisfy the requirements of different scenarios. Experimental results indicate that the circuit exhibits outstanding preformation in sparse event scenarios， with a maximum video compression ratio of up to 98%，which significantly enhances the efficiency of data transmission and processing.