The design method capable of using external synchronous for a camera with various data output formats, relating to data output of the camera. A transformation between an external synchronizing signal and a CCD (charge coupled device) time sequence is carried out by utilizing a programmable gate array module, so as to realize two-way communication with the external synchronization. A synchronizing signal is transmitted by externally connecting an input line module, an input field module, an input clock module and an input exposure module on FPGA (filed programmable gate array), and the two-way communication with the external synchronization is realized by externally connecting a circumscribed high-speed serial interface, a parallel interface, a low-voltage differential signal interface and a network interface. Software control FPGA uses an external control signal firstly. The control signal can be one or two or three or four of an input field synchronizing signal, an input line synchronizing signal, an input clock signal and an input exposure control signal. The external device can be added with a video compression chip, or an embedded chip, or both the video compression chip and the embedded chip. The invention enables the exposure time to be synchronous with a specific event, and to be synchronous with an operation processing of the external device, enables the software to program fast, and enables program running time and memory using to be less.