Design And Implementation Of Video Streaming Interface For Embedded Synchronous Reference Codes

Since the 80 s of last century,the BT.656 and BT.1120 protocols have played a more and more important role in digital video transmission by virtue of their few transmission lines and easy control.However,with the increase of video applications,the diversity of video resolution,the single resolution BT.656 and BT.1120 standard interface,can not meet the needs of modern society.Therefore,in order to solve the shortcomings of traditional BT.656 and BT.1120 transmission interface,which can only transmit fixed resolution video.Based on the research of the BT.656 and BT.1120 protocols,this paper designs and implements a video transmission interface with the embedded synchronous datum code based on the characteristics of the two protocols.The video resolution(high and wide)parameters and the original data format parameters are independent,and the user is set up by the configuration register according to the actual requirements.At the same time,it can transmit audio,subtitle and other auxiliary data according to the demand,and improve the transmission efficiency of the interface.It has good portability and scalability,and can transmit video of various formats and resolution.According to the data transmission process,the design is divided into two fully independent interfaces: the sending interface and the receiving interface.For the sending interface,AXI interface module based on AXI bus reading address channel and reading data channel is adopted in the design.In the control of reading data state machine,the original video data is read in the storage,and the format conversion module is used to transform the read data to obtain the interface support YCb Cr4:2:2 format data.Meanwhile,the data is buffered and cross-clock domain transmitted by the two-level FIFO module,and the code engine module uncovers the data and encodes the data flow.For receiving interface,according to the feature of embedded synchronization code,video data and auxiliary data are obtained from the input data stream by decoding module.The format conversion module converts the decoded video data to get the data type which needs to be stored.The two level FIFO module transmissions and caches the data into the clock domain and is based on the AXI write data channel and write address channel AXI interface module,under the control of write data state machine,write data to the specified location in memory.Finally,the two interfaces are simulated and verified by module level and system level respectively.The results show that the video transmission interface designed in this paper can achieve the transmission of multiple video data and achieve the desired requirements.