Rasterizing an image in Illustrator is a process that can be used to create a more realistic and detailed image. The first step is to create a new layer on the canvas and name it “Image.” Next, select the Rectangle tool and draw a rectangle around the Image layer. Make sure that the rectangle is large enough to cover the entire image. Next, select the Gradient tool and gradient all of the colors from black to white in different directions. Finally, use the Lasso tool to select all of the colors within the gradient and drag them into position on top of the rectangle created by the Gradient tool.