Techniques and/or systems for generating a two-dimensional projection image of an object under examination from helical data are provided herein. An image plane and a distance, or height, of an examination line lying in a plane parallel to the image plane may be selected with or without user input. Using the selected image plane and examination line, data may be extracted from one or more views indicative of the object. The data that is extracted from the respective views is generally indicative of rays that traverse the examination line and have a trajectory that meets predetermined criteria. Using the extracted data from a plurality of views, one or more projection lines that are substantially parallel to a corresponding image slice are produced and a two-dimensional projection image is generated.
