# sigpy.mri.poisson¶

sigpy.mri.poisson(img_shape, accel, calib=(0, 0), dtype=<class 'complex'>, crop_corner=True, return_density=False, seed=0, max_attempts=30, tol=0.1)[source]

Generate variable-density Poisson-disc sampling pattern.

The function generates a variable density Poisson-disc sampling mask with density proportional to $$1 / (1 + s |r|)$$, where $$r$$ represents the k-space radius, and $$s$$ represents the slope. A binary search is performed on the slope $$s$$ such that the resulting acceleration factor is close to the prescribed acceleration factor accel. The parameter tol determines how much they can deviate.

Parameters: img_shape (tuple of ints) – length-2 image shape. accel (float) – Target acceleration factor. Must be greater than 1. calib (tuple of ints) – length-2 calibration shape. dtype (Dtype) – data type. crop_corner (bool) – Toggle whether to crop sampling corners. seed (int) – Random seed. max_attempts (float) – maximum number of samples to reject in Poisson disc calculation. tol (float) – Tolerance for how much the resulting acceleration can deviate form accel. Poisson-disc sampling mask. array

References

Bridson, Robert. “Fast Poisson disk sampling in arbitrary dimensions.” SIGGRAPH sketches. 2007.