Aiming at the common display methods such as image superimposition and cross-screen stitching in the current video display field, the two functions often cannot be implemented in the same system at the same time, resulting in limitation of application scenarios. A hardware structure design of a multifunctional video stitching system is proposed. The system is based on a bilinear interpolation image algorithm. The pipeline design ideas are used to optimize the algorithm. At the same time, a single-chip computer is used to complete the calculation of the zoom factor and the transmission of display parameters before and after video processing. The whole process reduces the consumption of hardware resources, and also improves the efficiency of the algorithm. The design is verified in Diamond that is the development environment of Lattice. The results show that the FPGA can simultaneously process four input video stream storage operations and output four video signals of any resolution. In a 2 × 2 stitching matrix, the image overlay and cross-screen stitching can be achieved simultaneously. The stitching system supports a maximum resolution of 1 920 × 1 080 and an output with a minimum resolution of 50 × 50, achieving the expected result.