Research On Visualization Method Of The Cranial Part Perspective Based On Ray Casting Algorithm

Computer hardware is upgrading rapidly and software technology advances constantly,which has stimulated the significant progress of data three-dimensional visualization technology.The 3D visualization technology of medical volume data has changed the way of traditional medical diagnosis.Doctors no longer need to use the two-dimensional diagnostic images to construct relevant information about the lesions with subjective judgments,but can directly use the three-dimensional images for medical consultation and preoperative planning.This brings great convenience to the diagnosis and treatment of patients.The brain controls human activities and determines human thinking,and its importance is self-evident.Diagnosis and treatment of the brain require extreme caution.If you only visualize the volume data of the brain in three dimensions and observe and study its images,it is inevitable that you cannot accurately grasp the location information of the brain on the head.Therefore,this article proposes a visualization method to observe the brain in cranium through perspective.With the help of the method in this article,it is possible to directly observe the brain through the exoskeleton structure of the cranial part while retaining the overall contour information of the head.Through this visualization method,doctors can accurately grasp the size and location of brain lesions,which will facilitate subsequent diagnosis.The main innovation of this article concentrates in the following two aspects:First,for cranial data,a perspective visualization method is proposed based on the ray casting algorithm.This method can directly observe the brain structure in the cranium through the cranial tissue of the cranium by adjusting the opacity information of the cranial part.At the same time,with the help of graphics processing unit(GPU)powerful image display capabilities and image rendering capabilities,to enhance the visualization effect and speed of this method.Second,study the influence of the local illumination model on the imaging effect.In order to improve the imaging effect of the perspective visualization method,the thesis added three local lighting models,namely Lambert local lighting model,Lambert local lighting model with light attenuation effect and Phone local lighting model.Explore the effect of cranial perspective visualization under different local illumination models to meet different observation needs.Through the discussion and verification in the article,the cranial perspective visualization method based on the ray casting algorithm designed in this article can be used to observe the brain structure of the cranial part in a targeted manner while preserving the overall contour structure of the head.By adding Lambert local illumination model,the depth information of the image can be improved,and the threedimensional sense of the image can be increased.Adding the Lambert local lighting model including light attenuation can enhance the contrast of the visualized image and enhance the detailed information of the image.The local lighting model of the Phone is added to make the visualization effect look richer and fuller,and can better restore the real object model.