def psf_calc(self, psf, data_size):
"""Precalculate the OTF etc..."""
g = resizePSF(psf, data_size)
#keep track of our data shape
self.height = data_size[0]
self.width = data_size[1]
self.depth = data_size[2]
self.shape = data_size
self.FTshape = [self.shape[0], self.shape[1], self.shape[2] / 2 + 1]
self.g = g.astype('f4')
self.g2 = 1.0 * self.g[::-1, ::-1, ::-1]
#allocate memory
self.H = fftw3f.create_aligned_array(self.FTshape, 'complex64')
self.Ht = fftw3f.create_aligned_array(self.FTshape, 'complex64')
#self.f = np.zeros(self.shape, 'f4')
#self.res = np.zeros(self.shape, 'f4')
#self.S = np.zeros((np.size(self.f), 3), 'f4')
#self._F = fftw3f.create_aligned_array(self.FTshape, 'complex64')
#self._r = fftw3f.create_aligned_array(self.shape, 'f4')
#S0 = self.S[:,0]
#create plans & calculate OTF and conjugate transformed OTF
fftw3f.Plan(self.g, self.H, 'forward')()
fftw3f.Plan(self.g2, self.Ht, 'forward')()
self.Ht /= g.size
self.H /= g.size
def prep(self):
#allocate memory
self._F = fftw3f.create_aligned_array(self.FTshape, 'complex64')
self._r = fftw3f.create_aligned_array(self.shape[:-1], 'f4')
#calculate plans for other ffts
self._plan_r_F = fftw3f.Plan(self._r, self._F, 'forward')
self._plan_F_r = fftw3f.Plan(self._F, self._r, 'backward')
def __init__(self, u, v, k=None, lamb=488, n=1.51):
"""A FourierPropagator object allows us evaluate the electric field at a given defocus by propagating a complex
pupil distribution a given distance from the nominal focus by adding the relevant phase term to the pupil and
then taking the Fourier amplitude.
Parameters
==========
u, v : 2d arrays of float
the co-ordinates in spatial frequencies within the pupil plane
lamb : float
the wavelength in nm
n : float
the refractive index of the media
Notes
=====
u, v must be the same size as the eventual pupil distribution to be used. On creation, the FourierPropagator
pre-calculates the phase factor to add for each u, v, co-ordinate and also pre-computes FFTW3 plans for the
necessary Fourier transforms.
"""
if not k is None:
raise DeprecationWarning('k is no longer used')
#R = np.sqrt(u**2 + v**2)
self.propFac = ((2 * np.pi * n / lamb) *
np.sqrt(1 - np.minimum(u**2 + v**2, 1))).astype('f')
#self.pfm =(self.propFac > 0).astype('f')
self.pfm = (np.sqrt(u**2 + v**2) < 1).astype('f')
self._F = fftw3f.create_aligned_array(u.shape, 'complex64')
self._f = fftw3f.create_aligned_array(u.shape, 'complex64')
#print('Creating plans for FFTs - this might take a while')
#calculate plans for other ffts
self._plan_f_F = fftw3f.Plan(self._f,
self._F,
'forward',
flags=FFTWFLAGS,
nthreads=NTHREADS)
self._plan_F_f = fftw3f.Plan(self._F,
self._f,
'backward',
flags=FFTWFLAGS,
nthreads=NTHREADS)
#self._plan_F_f = fftw3f.Plan(self._F, self._f, 'backward', flags = FFTWFLAGS, nthreads=NTHREADS)
fftwWisdom.save_wisdom()
def prep(self):
#allocate memory
self._F = fftw3f.create_aligned_array(self.FTshape, 'complex64')
self._r = fftw3f.create_aligned_array(self.shape, 'f4')
print('Creating plans for FFTs - this might take a while')
#calculate plans for other ffts
self._plan_r_F = fftw3f.Plan(self._r, self._F, 'forward', flags = FFTWFLAGS, nthreads=NTHREADS)
self._plan_F_r = fftw3f.Plan(self._F, self._r, 'backward', flags = FFTWFLAGS, nthreads=NTHREADS)
fftwWisdom.save_wisdom()
print('Done planning')
def psf_calc(self, psf, data_size):
"""Precalculate the OTF etc..."""
g = resizePSF(psf, data_size)
#keep track of our data shape
self.height = data_size[0]
self.width = data_size[1]
self.depth = data_size[2]
self.shape = data_size
FTshape = [self.shape[0], self.shape[1], self.shape[2] / 2 + 1]
#allocate memory
self.H = fftw3f.create_aligned_array(FTshape, 'complex64')
self.Ht = fftw3f.create_aligned_array(FTshape, 'complex64')
self._F = fftw3f.create_aligned_array(FTshape, 'complex64')
self._r = fftw3f.create_aligned_array(self.shape, 'f4')
self.g = g.astype('f4')
self.g2 = 1.0 * self.g[::-1, ::-1, ::-1]
#S0 = self.S[:,0]
#create plans & calculate OTF and conjugate transformed OTF
fftw3f.Plan(self.g, self.H, 'forward')()
fftw3f.Plan(self.g2, self.Ht, 'forward')()
self.Ht /= g.size
self.H /= g.size
self.H2 = self.Ht * self.H
#calculate plans for other ffts
self._plan_r_F = fftw3f.Plan(self._r,
self._F,
'forward',
flags=FFTWFLAGS,
nthreads=NTHREADS)
self._plan_F_r = fftw3f.Plan(self._F,
self._r,
'backward',
flags=FFTWFLAGS,
nthreads=NTHREADS)
fftwWisdom.save_wisdom()
self.lamb = None
def psf_calc(self, psf, data_size):
"""Precalculate the OTF etc..."""
g = resizePSF(psf, data_size)
#normalise
g /= g[:, :, g.shape[2] / 2].sum()
#keep track of our data shape
self.height = data_size[0]
self.width = data_size[1]
self.depth = data_size[2]
self.shape = data_size
self.FTshape = list(
self.shape[:-1]
) #[self.shape[0], self.shape[1], self.shape[2]/2 + 1]
self.FTshape[-1] = self.FTshape[-1] / 2 + 1
self.g = g.astype('f4')
self.g2 = 1.0 * self.g[::-1, ::-1, :]
self.H = []
self.Ht = []
for i in range(self.shape[-1]):
#allocate memory
self.H.append(
fftw3f.create_aligned_array(self.FTshape, 'complex64'))
self.Ht.append(
fftw3f.create_aligned_array(self.FTshape, 'complex64'))
#create plans & calculate OTF and conjugate transformed OTF
fftw3f.Plan(1.0 * self.g[:, :, i], self.H[i], 'forward')()
fftw3f.Plan(1.0 * self.g2[:, :, i], self.Ht[i], 'forward')()
self.Ht[i] /= g[:, :, i].size
self.H[i] /= g[:, :, i].size
def resizePSF(psf, data_size):
if not psf.shape == data_size:
#Expand PSF to data size by fourier domain interpolation
print('Resizing PSF to match data size')
g_ = fftw3f.create_aligned_array(data_size, 'complex64')
H_ = fftw3f.create_aligned_array(data_size, 'complex64')
sx, sy, sz = numpy.array(data_size).astype('f') / psf.shape
#print sx, sy, sz
OT = fftshift(fftn(
fftshift(psf))) #don't bother with FFTW here as raw PSF is small
if data_size[2] > 1:
pr = ndimage.zoom(OT.real, [sx, sy, sz], order=1)
pi = ndimage.zoom(OT.imag, [sx, sy, sz], order=1)
else: #special case for 2D
pr = ndimage.zoom(OT.real.squeeze(), [sx, sy],
order=1).reshape(data_size)
pi = ndimage.zoom(OT.imag.squeeze(), [sx, sy],
order=1).reshape(data_size)
H_[:] = ifftshift(pr + 1j * pi)
fftw3f.Plan(H_, g_, 'backward')()
#View3D(psf)
#View3D(H_)
#View3D(OT)
#View3D(pr)
g = ifftshift(g_.real).clip(
min=0) # negative values may cause instability
print('PSF resizing complete')
else:
g = psf
#View3D(psf)
#View3D(fftshift(numpy.abs(H_)))
#View3D(fftshift(numpy.angle(H_)))
#View3D(g)
return g / g.sum()
