An OSD Scheme Design Based On Data Compression

OSD (On Screen Display) is a part of video. It's mainly about the information that displayed on the screen beside the video, such as the menu, prompting message, etc.A new design of bitmap OSD expounded in this paper is based on data compression. The purpose of this design is to reduce the cost of bitmap OSD system by compressing the data in program memory and decompress it before they are used.Firstly, a new design scheme was proposed in this paper, some coding schemes were discussed and an improving RLE encoding algorithm was presented.Then some skills of ASIC design in Verilog HDL were discussed and the designs of 3 modules including RLE decompression module were finished in this paper.Moreover, the development and the prospect of OSD were discussed at the end of the paper.