FPGA-based compression of streaming x-ray photon correlation spectroscopy data

A data acquisition system to perform real-time background subtraction and lower-level-discrimination-based compression of streaming x-ray photon correlation spectroscopy (XPCS) data from a fast charge-coupled device (CCD) area detector has been built and put into service at the Advanced Photon source (APS) at Argonne National Laboratory. A commercial frame grabber with on-board field-programmable gate array (FPGA) was used in the design, and continuously processes 60 frames per second each consisting of 1,024 × 1,024 pixels with up to 64512 photon hits per frame.