calc_refined_offsets

jwst.wfs_combine.wfs_combine.calc_refined_offsets(sci_nai_1, sci_nai_2, off_x, off_y, psf_size)[source]

Get overlap of the two images and calculate 2D cross correlation between the two subarrays.

The overlap image is based on the offsets. Then we slice on a subarray around the peak of the cross correlation image and find the first moment. The first moment provides a high S/N measurement of the offset between the two images.

Parameters:
sci_nai_1ndarray

Nominally aligned, interpolated SCI subarray (float) for image 1

sci_nai_2ndarray

Nominally aligned, interpolated SCI subarray (float) for image 2

off_xint

Offset in x-direction

off_yint

Offset in y-direction

psf_sizeint

The worst case PSF size

Returns:
refined_xfloat

The refined value of the x offset

refined_yfloat

The refined value of the y offset