Adaptive and dynamic ordering of illumination patterns with an image dictionary in single-pixel imaging

Single-pixel imaging (SPI) is a novel optical imaging technique capable of handling unusual imaging conditions such as invisible wavebands and indirect line of sight. In SPI, the target object is sequentially illuminated with various structured-light patterns and a single-pixel detector is used to collect the total light intensity. Unlike conventional imaging, a pixelated sensor array is replaced with a single-pixel detector in SPI but the trade-off is that massive measurements are required to recover an object image with acceptable quality. To shorten the length of projection pattern sequence and image capturing time, it is feasible to arrange the illumination patterns in an optimized sequential order. For common Fourier SPI, we propose a novel scheme to adaptively and dynamically determine the order of illumination patterns based on the average spectrum of training images and the feedback of recorded single-pixel intensity values. Simulated and experimental results indicate that our proposed scheme can significantly enhance the imaging quality under low sampling rates.