def paddingFourier(arr, shape, value=0, interpolate=True):
"""
arr: assuming origin at 0, rfft product (half x size), up to 3D
shape: target shape
value: the value to fill in empty part
interpolate: shift by interpolation if necessary
return array with target shape
"""
# prepare buffer
dtype = arr.dtype.type
canvas = N.empty(shape, dtype)
canvas[:] = value
# calc and shift
shapeS = N.array(arr.shape)
shapeL = N.asarray(shape)
halfS = shapeS / 2.
subpx_shift = halfS % 1
if interpolate and N.sometrue(subpx_shift):
arr = U.nd.shift(arr, subpx_shift)
# create empty list for slices
nds = arr.ndim - 1
choices = ['slice(halfS[%i])', 'slice(-halfS[%i], None)']
nchoices = len(choices)
nds2 = nds**2
slcs = []
for ns in range(nds2):
slcs.append([])
for n in range(nchoices * nds):
slcs[ns].append(
[Ellipsis]) # Ellipsis help to make arbitray number of list
# fill the empty list by slice (here I don't know how to use 4D..)
for i in range(nds2):
for d in range(nds):
for x in range(nds):
for c, choice in enumerate(choices):
if d == 0 and x == 0:
idx = x * (nchoices) + c
else: # how can I use 4D??
idx = x * (nchoices) + (nchoices - 1) - c
exec('content=' + choice % d)
slcs[i][idx] += [content]
# cutout and paste
for slc in slcs:
for s in slc:
s.append(slice(shapeS[-1]))
#print s
canvas[s] = arr[s]
return canvas
def _smoothBorder(arr, start, stop, smooth, value):
"""
start, stop: [z,y,x]
"""
# prepare coordinates
shape = N.array(arr.shape)
start = N.ceil(start).astype(N.int16)
stop = N.ceil(stop).astype(N.int16)
smooth_start = start - smooth
smooth_stop = stop + smooth
smooth_start = N.where(smooth_start < 0, 0, smooth_start)
smooth_stop = N.where(smooth_stop > shape, shape, smooth_stop)
#print smooth_start, smooth_stop
import copy
sliceTemplate = [slice(None, None, None)] * arr.ndim
shapeTemplate = list(shape)
for d in range(arr.ndim):
smooth_shape = shapeTemplate[:d] + shapeTemplate[d + 1:]
# make an array containing the edge value
edges = N.empty([2] + smooth_shape, N.float32)
# start side
slc = copy.copy(sliceTemplate)
slc[d] = slice(start[d], start[d] + 1, None)
edges[0] = arr[slc].reshape(smooth_shape)
# stop side
slc = copy.copy(sliceTemplate)
slc[d] = slice(stop[d] - 1, stop[d], None)
edges[1] = arr[slc].reshape(smooth_shape)
edges = (edges - value) / float(
smooth + 1) # this value can be array??
# both side
for s, side in enumerate([start, stop]):
if s == 0:
rs = range(smooth_start[d], start[d])
rs.sort(reverse=True)
elif s == 1:
rs = range(stop[d], smooth_stop[d])
# smoothing
for f, i in enumerate(rs):
slc = copy.copy(sliceTemplate)
slc[d] = slice(i, i + 1, None)
edgeArr = edges[s].reshape(arr[slc].shape)
#arr[slc] += edgeArr * (smooth - f)
arr[slc] = arr[slc] + edgeArr * (smooth - f) # casting rule
arr = N.ascontiguousarray(arr)
return arr
def radialaverage(data, center=None, useMaxShape=False):
"""
data: ND array
center: coordinate of center of radii
useMinShape: the output uses the maximum shape available
return 1D array
"""
if center is None:
center = N.array(data.shape) // 2
if len(center) != data.ndim:
raise ValueError, 'dimension of center (%i) does not match the dimension of data (%i)' % (
len(center), data.ndim)
zyx = N.indices((data.shape))
r = N.zeros(data.shape, N.float32)
for i, t in enumerate(zyx):
r += (t - center[i])**2
r = N.sqrt(r)
#y, x = N.indices((data.shape))
#r = N.sqrt((x - center[0])**2 + (y - center[1])**2) # distance from the center
r = r.astype(N.int)
if data.dtype.type in (N.complex64, N.complex128):
rbin = N.bincount(r.ravel(), data.real.ravel())
ibin = N.bincount(r.ravel(), data.imag.ravel())
tbin = N.empty(rbin.shape, data.dtype.type)
tbin.real = rbin
tbin.imag = ibin
else:
tbin = N.bincount(r.ravel(), data.ravel())
nr = N.bincount(r.ravel())
radialprofile = tbin / nr.astype(N.float32)
if not useMaxShape:
minShape = min(list(N.array(data.shape) - center) + list(center))
radialprofile = radialprofile[:minShape]
return radialprofile
def paddingValue(img, shape, value=0, shift=None, smooth=0, interpolate=True):
"""
shape: in the same dimension as img
value: value in padded region, can be scaler or array with the shape
shift: scaler or in the same dimension as img and shape (default 0)
smooth: scaler value to smoothen border (here value must be scaler)
interpolate: shift array by subpixel interpolation to adjust center
return: padded array with shape
"""
# create buffer
dtype = img.dtype.type
canvas = N.empty(shape, dtype)
canvas[:] = value
# calculate position
shape = N.array(shape)
shapeS = img.shape
center = N.divide(shape, 2)
if shift is None:
shift = 0 #[0] * len(shapeS)
shapeL = shape #N.add(shapeS, center+shift)
start, stop = (shapeL - shapeS) / 2., (shapeL + shapeS) / 2.
slc = [slice(start[d], stop[d], None) for d in range(img.ndim)]
#print slc, shapeS, shapeL
# shift if necessary
if interpolate:
subpx_shift = start % 1 # should be 0.5 or 0
if N.sometrue(subpx_shift):
img = U.nd.shift(img, subpx_shift)
# padding
canvas[slc] = img
if smooth:
canvas = _smoothBorder(canvas, start, stop, smooth, value)
canvas = N.ascontiguousarray(canvas)
#print shapeS, shapeL, slc
return canvas
def radialAverage2D(arr, center=None, useMaxShape=False):
"""
2D-wise radial average
arr: ND (>2) array
center: 2D center to radial average
return ND-1 array
"""
if arr.ndim == 2:
return radialaverage(arr, center, useMaxShape)
for t, img in enumerate(arr):
if img.ndim >= 3:
ra = radialaverage2D(img, center, useMaxShape)
else: # 2D
ra = radialaverage(img, center, useMaxShape)
try:
canvas[t] = ra
except NameError: # canvas was not defined yet
canvas = N.empty((arr.shape[0], ) + ra.shape, ra.dtype.type)
canvas[t] = ra
return canvas