npix_pill_center

npix_pill_center(x, y, w, a, b, theta=0.0, *, shape, mask=None, validate=True)

Return center-selected pill-aperture effective in-frame pixel counts.

Parameters

x, y : scalar or array_like: Aperture center coordinates in pixel units. Shapes must match after numpy.atleast_1d. The return shape matches that broadcast-free input shape, so scalar inputs return one-element arrays.
w, a, b : float: Pill rectangle length and cap semiaxes in pixels.
theta : float, optional = 0.0: Rotation angle in radians, measured counterclockwise from the positive x axis.
shape : tuple[int, int]: Image shape as (ny, nx) used to clip the aperture footprint.
mask : array_like of bool, optional = None: Boolean image mask with shape shape. True pixels are excluded from the returned effective pixel count.

Pill center-mode aperture summation currently uses Rust-generated bbox-tight binary pill weights and the same BoundingBox.apsum reduction.