Research On Real-Time Correction Algorithm And Circuit Architecture For Gray Value Of Video Image

With the rapid development of display technology and camera technology,the display of video and image plays an important role in people's daily life.People have higher and higher requirements on the quality of video images.There are two urgent needs for improving the quality of video images.First,the contrast between the parts of the image,especially for the video images captured in the complex lighting background is poor,which seriously restricts the overall beauty of the image.Second,the video resolution refers to ultra-high definition from SD,makes the amount of image data to be processed continuously increased,and thus the performance of the video signal processing platform are continuously improved.Aiming at the problems that the background light is dark under the point source,the contrast of the dark portion of the captured video image is poor,and the detail information is lost,a region Gamma correction algorithm based on quadratic threshold segmentation is proposed.Based on the image gray level threshold and image information obtained through the maximum inter-class variance method(Otsu),the proposed algorithm uses the histogram trough method to perform secondary threshold segmentation.Finally,the pixel value is subjected to regional Gamma correction and information fusion.the process of.Based on the AX415-FPGA development platform,this study proposes a hardware circuit system solution,including OV7670 image acquisition module,SDRAM pingpong interaction module,image gray correction module and VGA display module.The whole system module is driven by Verilog language.In order to improve the processing rate of image gray information,the stored image information is read by using the pingpong interactive read-write mode.In this study,MATLAB simulation is used to select the average low degree and information entropy of the image as the evaluation criteria to verify the correctness of the region Gamma correction algorithm based on quadratic threshold segmentation,that is,it has better gradation correction and information restoration effect.In this study,the hardware circuit system is built as the core,through which realizes the image gray value correction,and improves the processing rate of the reading and writing of pixel values.