A new real-time imaging scheme is proposed based on low-rank spatiotemporal decomposition. Briefly, a high-quality spatial subspace and a direct linear mapping from k-space navigator data to subspace coordinates are first learned from a “demo” scan. In the subsequent “live” scan, successive real-time images can be generated by a fast matrix multiplication procedure on a single instance of the k-space navigator readout (e.g. a single k-space line), which can be acquired at a high temporal rate. The method was demonstrated in vivo using a T1-T2 abdominal multitasking sequence.