I have a 3D CT image of a car engine in raw form with no header information. When loaded into numpy array as 16 bit unsigned integer, I noticed that the values range between 0 to 52000. Is this normal for a CT Image? When viewing the image, I notice a lot of cloud like noise around the parts. I'm trying to extract features using a deep learning method. This is my first time working with CT Images. What pre processing is neccesary for such CT Images?