webbpsf_ext.image_manip.rotate_shift_image

webbpsf_ext.image_manip.rotate_shift_image(hdul, index=0, angle=0, delx_asec=0, dely_asec=0, shift_func=<function fshift>, reshape=False, **kwargs)[source]

Rotate/Shift image

Rotate then offset image by some amount. Positive angles rotate the image counter-clockwise.

Parameters:

  • hdul (HDUList) – Input HDUList

  • index (int) – Specify HDU index, usually 0

  • angle (float) – Rotate entire scene by some angle. Positive angles rotate counter-clockwise.

  • delx_asec (float) – Offset in x direction (specified in arcsec). Pixel scale should be included in header keyword ‘PIXELSCL’.

  • dely_asec (float) – Offset in x direction (specified in arcsec). Pixel scale should be included in header keyword ‘PIXELSCL’.

  • shift_func (function) – Function to use for shifting. Usually either fshift or fourier_imshift.

Keyword Arguments:

  • order (int, optional) – The order of the spline interpolation, default is 3. The order has to be in the range 0-5. This also determines the interpolation value of the shift function if interp is not set. if order <=1: interp=’linear’; if order <=3; otherwise interp=’cubic’.

  • interp (str, optional) – Interpolation method to use for shifting using ‘fshift’ or ‘opencv. If not set, will default to method as described by order keyword. For ‘opencv’, valid options are ‘linear’, ‘cubic’, and ‘lanczos’. for ‘fshift’, valid options are ‘linear’, ‘cubic’, and ‘quintic’.

  • else – interp=’quintic’

  • mode ({'reflect', 'constant', 'nearest', 'mirror', 'wrap'}, optional) –

    The mode parameter determines how the input array is extended beyond its boundaries. Default is ‘constant’. Behavior for each valid value is as follows:

    ’reflect’ (d c b a | a b c d | d c b a)

    The input is extended by reflecting about the edge of the last pixel.

    ’constant’ (k k k k | a b c d | k k k k)

    The input is extended by filling all values beyond the edge with the same constant value, defined by the cval parameter.

    ’nearest’ (a a a a | a b c d | d d d d)

    The input is extended by replicating the last pixel.

    ’mirror’ (d c b | a b c d | c b a)

    The input is extended by reflecting about the center of the last pixel.

    ’wrap’ (a b c d | a b c d | a b c d)

    The input is extended by wrapping around to the opposite edge.

  • cval (scalar, optional) – Value to fill past edges of input if mode is ‘constant’. Default is 0.0.

  • prefilter (bool, optional) – Determines if the input array is prefiltered with spline_filter before interpolation. The default is True, which will create a temporary float64 array of filtered values if order > 1. If setting this to False, the output will be slightly blurred if order > 1, unless the input is prefiltered, i.e. it is the result of calling spline_filter on the original input.