Design Of Pixel Processing Based On VR Video Display Chip

In the virtual reality(VR)system,users can experience the virtual system environment through stereo vision information.In the process of forming the stereo vision of VR device,the video display chip makes the image form a visual differentiated image through the technology of pixel color segmentation,and finally displays it on the device panel.This thesis comes from the enterprise's VR video display chip research and development project.This chip is a video stream bridge chip in the head mounted VR device,which mainly realizes the function of video stream input from the Display Port(DP)to the output of MIPI interface,and stereoscopic display of video stream on the terminal panel.The pixel processing module in the chip architecture is a new optimization design compared with the previous generation products,which can effectively solve the problems of low resolution and unstable display of previous VR devices.The image pixel processing module for the input video stream can make the downstream module get the required monochromatic field data.Finally,one frame video is divided into red,green and blue colors and projected onto the LCo S panel in turn,and the stereoscopic display effect is realized through the differentiation of human vision.In this thesis,the top-down design method is used in VNC tool software under Linux operating system,and the RTL design description of pixel processing module in VR video display chip is completed based on Verilog HDL hardware language.First of all,the pixel processing module needs to receive the digital video stream sent by the DP terminal or splash screen module.According to the characteristic requirements of the function of the pixel processing,module complete the sub module division and working mode division,design the pixel color segmentation method under different working modes and different input video resolution,and realize the RGB segmentation of the video stream picture.And the segmented monochromatic field data is spliced according to the burst transmission format.Then,the segmented data of each frame of video stream is stored in SRAM to complete the design of SRAM storage mechanism that meets the design requirements of VR video display chip.Based on this mechanism,the segmented data transmitted across clock domain is stored in SRAM,so that the CPU can read the data from SRAM through AXI bus and transmit it to the terminal device for subsequent processing of VR stereoscopic display.In the stored procedure,the pixel processing module also completes the handshake interaction function with the CPU,and sends an interrupt signal to the CPU to indicate when to start accessing SRAM.Finally,the pixel processing module is statically verified based on Spy Glass platform,and the RTL code is checked for connectivity and cross clock domain.The UVM verification platform is built based on UVM platform,and the test cases are written according to the function points,the simulation waveforms are analyzed.The simulation results show that the pixel processing module designed in this paper realizes the color segmentation and SRAM storage functions of pixels in different input video formats,and the code coverage and function coverage are 100%,which meets the design requirements.The pixel processing module can capture the video information of each frame according to the resolution and pixel format of the input video stream.The LCo S panel scans the monochromatic field data divided by the module time-sharing,which can effectively improve the video processing efficiency of the chip system and the display refresh speed of the terminal panel in VR devices.