High-definition serial digital interface data converting method and device

The invention is suitable for the technical field of security monitoring, and provides a high-definition serial digital interface data converting method and device. The high-definition serial digital interface data converting method comprises the steps of: writing high 2 orders of brightness Y data in video data of parallel 4:2:2 into a high-order brightness cache, low 2 orders into a low-order brightness cache; deleting chroma Cr data of half line numbers in the video data, writing high 8 orders of the chroma Cr data into a high-order chroma cache, low 2 order data into a low-order chroma cache, deleting chroma Cr data in the other half line numbers, writing high 8 orders of the chroma Cb data into the high-order chroma cache, low 2 order data into the low-order chroma cache; and writing prepared 4:2:0 video data in the high-order brightness cache, the low-order brightness cache, the high-order chroma cache and the low-order chroma cache into a storage. According to the invention, high-definition video data is transmitted through a gigabit Ethernet under the premise of no compression of the video data, and the solution of high-definition video transmission is enriched.