Robust and Efficient Alignment of Calcium Imaging Data through Simultaneous Low Rank and Sparse Decomposition

Accurate alignment of calcium imaging data, which is critical for the extraction of neuronal activity signals, is often hindered by the image noise and the neuronal activity itself. To address the problem, we propose an algorithm named REALS for robust and efficient batch image alignment through simultaneous transformation and low rank and sparse decomposition. REALS is constructed upon our finding that the low rank subspace can be recovered via linear projection, which allows us to perform simultaneous image alignment and decomposition with gradient-based updates. REALS achieves orders-of-magnitude improvement in terms of accuracy and speed compared to the state-of-the-art robust image alignment algorithms.