Design And Application Of Network Based OSD Display Interface Of The Video Decoder Unit In The Metro

The metro is now a requisite means of transportation of large or medium-sized cities. Providing the HD video information and accurate text for passengers is one of the important demands. In the past, metro needs Media Player System and LED Display System to manage the video information and the content respectively. Now the Video Encoder/Decoder Unit in the metro can provide passengers a set of video information or live content from TV, which doesn’t include text content. Therefore, a new developing demand is raised for the Video Encoder/Decoder Unit in the metro. The Decoder Unit can not only operate decoding the video but also blend the video window and OSD bitmap window. In this way, both video information and text content could display for the passengers.According to the requirements above, a new digital video transformation framework and the Decoder Unit in this framework are introduced in this thesis. At last the thesis focuses on the design and development of the OSD Display Interface of the Video Decoder based on the network in the metro, which makes the blending of the video window and the OSD bitmap window on the TI TMS320DM368. OSD Display Interface is developed by the Linux embedded OS and Qt graphics library. It can create windows, set windows, display windows and manage windows. The windows can display anywhere and any style on the LCD. It provides passengers HD video information together with the vivid text content. Up to the present day, this OSD Display Interface has been tested already.