FIGURE 1.

The 3D amplified MRI (aMRI) algorithm pipeline. The volumetric/multi‐slice cine MRI is decomposed by the 3D complex steerable pyramid into scales and orientations. The colors represent the frequency response of the different filters (scales and orientations). Each filter is a bandpass with specific orientation and satisfies Equation (5). Small amplitudes have been zeroed in order to emphasize the filter's conic shape. The phases of the decomposition are separated from the amplitude component, and independently temporally band pass filtered at each spatial location, orientation, and scale. The filtered phases are then “spatially” filtered again to increase the phases signal‐to‐noise ratio using amplitude‐weighted Gaussian spatial smoothing, and then multiplied by an amplification parameter and added to the original amplitude component. The 4D data are then reconstructed to produce an amplified 4D movie