This Phase I proposal describes (1) an automated image quality assessment (IQA) software to objectively quantify image quality of airport security X-ray imaging systems for both checked and carry-on baggage and (2) a design for a novel test phantom specialized for security CT scanners. For fixed images, automated algorithms will measure the Modulation Transfer Function (MTF) and Contrast-to-Noise Ratio (CNR) of scan images; for moving images, automated algorithms will measure the uniformity of the horizontal speed of the object on the screen. These powerful automated IQA algorithms will objectively quantify image quality, without human intervention. For IQA of line scanners for carry-on baggage, we will use the existing ASTM phantom test object; for IQA of CT scanners for checked baggage, we will use a new test phantom, the TSS CT Phantom (TCP), which will be designed and built during this project. Given the widespread use of the MTF and CNR in IQA of medical X-ray imaging systems and that TCP is adapted from a prevalent medical CT phantom, Phase I efforts begin from TRL 2. Phase I mostly involves developing software and hardware-(1) the preliminary design and building of TCP prototype and (2) developing automated IQA algorithms-and concludes with performing experimental tests of the algorithms on available data (TRL 4). An on-site comparative analysis between human screener IQA and automated (algorithmic) IQA of real baggage data is expected at the end of Phase II.
