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import numpy as np
import unittest
import astra
import math
import pylab
# Display sinograms with mismatch on test failure
DISPLAY=False
NONUNITDET=True
OBLIQUE=True
FLEXVOL=True
NONSQUARE=False # non-square pixels not supported yet by most projectors
# Round interpolation weight to 8 bits to emulate CUDA texture unit precision
CUDA_8BIT_LINEAR=True
CUDA_TOL=2e-2
nloops = 50
seed = 123
# KNOWN FAILURES:
# fan/strip relatively high numerical errors around 45 degrees
# return length of intersection of the line through points src = (x,y)
# and det (x,y), and the rectangle defined by xmin, ymin, xmax, ymax
def intersect_line_rectangle(src, det, xmin, xmax, ymin, ymax):
EPS = 1e-5
if np.abs(src[0] - det[0]) < EPS:
if src[0] >= xmin and src[0] < xmax:
return ymax - ymin
else:
return 0.0
if np.abs(src[1] - det[1]) < EPS:
if src[1] >= ymin and src[1] < ymax:
return xmax - xmin
else:
return 0.0
n = np.sqrt((det[0] - src[0]) ** 2 + (det[1] - src[1]) ** 2)
check = [ (-(xmin - src[0]), -(det[0] - src[0]) / n ),
(xmax - src[0], (det[0] - src[0]) / n ),
(-(ymin - src[1]), -(det[1] - src[1]) / n ),
(ymax - src[1], (det[1] - src[1]) / n ) ]
pre = [ -np.Inf ]
post = [ np.Inf ]
for p, q in check:
r = p / (1.0 * q)
if q > 0:
post.append(r) # exiting half-plane
else:
pre.append(r) # entering half-plane
end_r = np.min(post)
start_r = np.max(pre)
if end_r > start_r:
return end_r - start_r
else:
return 0.0
def intersect_line_rectangle_feather(src, det, xmin, xmax, ymin, ymax, feather):
return intersect_line_rectangle(src, det,
xmin-feather, xmax+feather,
ymin-feather, ymax+feather)
def intersect_line_rectangle_interval(src, det, xmin, xmax, ymin, ymax, f):
a = intersect_line_rectangle_feather(src, det, xmin, xmax, ymin, ymax, -f)
b = intersect_line_rectangle(src, det, xmin, xmax, ymin, ymax)
c = intersect_line_rectangle_feather(src, det, xmin, xmax, ymin, ymax, f)
return (a,b,c)
# x-coord of intersection of the line (src, det) with the horizontal line at y
def intersect_line_horizontal(src, det, y):
EPS = 1e-5
if np.abs(src[1] - det[1]) < EPS:
return np.nan
t = (y - src[1]) / (det[1] - src[1])
return src[0] + t * (det[0] - src[0])
# y-coord of intersection of the line (src, det) with the vertical line at x
def intersect_line_vertical(src, det, x):
src = ( src[1], src[0] )
det = ( det[1], det[0] )
return intersect_line_horizontal(src, det, x)
# length of the intersection of the strip with boundaries edge1, edge2 with the horizontal
# segment at y, with horizontal extent x_seg
def intersect_ray_horizontal_segment(edge1, edge2, y, x_seg):
e1 = intersect_line_horizontal(edge1[0], edge1[1], y)
e2 = intersect_line_horizontal(edge2[0], edge2[1], y)
if not (np.isfinite(e1) and np.isfinite(e2)):
return np.nan
(e1, e2) = np.sort([e1, e2])
(x1, x2) = np.sort(x_seg)
l = np.max([e1, x1])
r = np.min([e2, x2])
return np.max([r-l, 0.0])
def intersect_ray_vertical_segment(edge1, edge2, x, y_seg):
# mirror edge1 and edge2
edge1 = [ (a[1], a[0]) for a in edge1 ]
edge2 = [ (a[1], a[0]) for a in edge2 ]
return intersect_ray_horizontal_segment(edge1, edge2, x, y_seg)
# weight of the intersection of line with the horizontal segment at y, with horizontal extent x_seg
# using linear interpolation
def intersect_line_horizontal_segment_linear(src, det, y, x_seg, inter_width):
EPS = 1e-5
x = intersect_line_horizontal(src, det, y)
assert(x_seg[1] - x_seg[0] + EPS >= inter_width)
if x < x_seg[0] - 0.5*inter_width:
return 0.0
elif x < x_seg[0] + 0.5*inter_width:
return (x - (x_seg[0] - 0.5*inter_width)) / inter_width
elif x < x_seg[1] - 0.5*inter_width:
return 1.0
elif x < x_seg[1] + 0.5*inter_width:
return (x_seg[1] + 0.5*inter_width - x) / inter_width
else:
return 0.0
def intersect_line_vertical_segment_linear(src, det, x, y_seg, inter_height):
src = ( src[1], src[0] )
det = ( det[1], det[0] )
return intersect_line_horizontal_segment_linear(src, det, x, y_seg, inter_height)
def area_signed(a, b):
return a[0] * b[1] - a[1] * b[0]
# is c to the left of ab
def is_left_of(a, b, c):
EPS = 1e-5
return area_signed( (b[0] - a[0], b[1] - a[1]), (c[0] - a[0], c[1] - a[1]) ) > EPS
# compute area of rect on left side of line
def halfarea_rect_line(src, det, xmin, xmax, ymin, ymax):
pts = ( (xmin,ymin), (xmin,ymax), (xmax,ymin), (xmax,ymax) )
pts_left = list(filter( lambda p: is_left_of(src, det, p), pts ))
npts_left = len(pts_left)
if npts_left == 0:
return 0.0
elif npts_left == 1:
# triangle
p = pts_left[0]
xd = intersect_line_horizontal(src, det, p[1]) - p[0]
yd = intersect_line_vertical(src, det, p[0]) - p[1]
ret = 0.5 * abs(xd) * abs(yd)
return ret
elif npts_left == 2:
p = pts_left[0]
q = pts_left[1]
if p[0] == q[0]:
# vertical intersection
x1 = intersect_line_horizontal(src, det, p[1]) - p[0]
x2 = intersect_line_horizontal(src, det, q[1]) - q[0]
ret = 0.5 * (ymax - ymin) * (abs(x1) + abs(x2))
return ret
else:
assert(p[1] == q[1])
# horizontal intersection
y1 = intersect_line_vertical(src, det, p[0]) - p[1]
y2 = intersect_line_vertical(src, det, q[0]) - q[1]
ret = 0.5 * (xmax - xmin) * (abs(y1) + abs(y2))
return ret
else:
# mirror and invert
ret = ((xmax - xmin) * (ymax - ymin)) - halfarea_rect_line(det, src, xmin, xmax, ymin, ymax)
return ret
# area of intersection of the strip with boundaries edge1, edge2 with rectangle
def intersect_ray_rect(edge1, edge2, xmin, xmax, ymin, ymax):
s1 = halfarea_rect_line(edge1[0], edge1[1], xmin, xmax, ymin, ymax)
s2 = halfarea_rect_line(edge2[0], edge2[1], xmin, xmax, ymin, ymax)
return abs(s1 - s2)
# width of projection of detector orthogonal to ray direction
# i.e., effective detector width
def effective_detweight(src, det, u):
ray = np.array(det) - np.array(src)
ray = ray / np.linalg.norm(ray, ord=2)
return abs(area_signed(ray, u))
# LINE GENERATORS
# ---------------
#
# Per ray these yield three lines, at respectively the center and two edges of the detector pixel.
# Each line is given by two points on the line.
# ( ( (p0x, p0y), (q0x, q0y) ), ( (p1x, p1y), (q1x, q1y) ), ( (p2x, p2y), (q2x, q2y) ) )
def gen_lines_fanflat(proj_geom):
angles = proj_geom['ProjectionAngles']
for theta in angles:
#theta = -theta
src = ( math.sin(theta) * proj_geom['DistanceOriginSource'],
-math.cos(theta) * proj_geom['DistanceOriginSource'] )
detc= (-math.sin(theta) * proj_geom['DistanceOriginDetector'],
math.cos(theta) * proj_geom['DistanceOriginDetector'] )
detu= ( math.cos(theta) * proj_geom['DetectorWidth'],
math.sin(theta) * proj_geom['DetectorWidth'] )
src = np.array(src, dtype=np.float64)
detc= np.array(detc, dtype=np.float64)
detu= np.array(detu, dtype=np.float64)
detb= detc + (0.5 - 0.5*proj_geom['DetectorCount']) * detu
for i in range(proj_geom['DetectorCount']):
yield ((src, detb + i * detu),
(src, detb + (i - 0.5) * detu),
(src, detb + (i + 0.5) * detu))
def gen_lines_fanflat_vec(proj_geom):
v = proj_geom['Vectors']
for i in range(v.shape[0]):
src = v[i,0:2]
detc = v[i,2:4]
detu = v[i,4:6]
detb = detc + (0.5 - 0.5*proj_geom['DetectorCount']) * detu
for i in range(proj_geom['DetectorCount']):
yield ((src, detb + i * detu),
(src, detb + (i - 0.5) * detu),
(src, detb + (i + 0.5) * detu))
def gen_lines_parallel(proj_geom):
angles = proj_geom['ProjectionAngles']
for theta in angles:
ray = ( math.sin(theta),
-math.cos(theta) )
detc= (0, 0 )
detu= ( math.cos(theta) * proj_geom['DetectorWidth'],
math.sin(theta) * proj_geom['DetectorWidth'] )
ray = np.array(ray, dtype=np.float64)
detc= np.array(detc, dtype=np.float64)
detu= np.array(detu, dtype=np.float64)
detb= detc + (0.5 - 0.5*proj_geom['DetectorCount']) * detu
for i in range(proj_geom['DetectorCount']):
yield ((detb + i * detu - ray, detb + i * detu),
(detb + (i - 0.5) * detu - ray, detb + (i - 0.5) * detu),
(detb + (i + 0.5) * detu - ray, detb + (i + 0.5) * detu))
def gen_lines_parallel_vec(proj_geom):
v = proj_geom['Vectors']
for i in range(v.shape[0]):
ray = v[i,0:2]
detc = v[i,2:4]
detu = v[i,4:6]
detb = detc + (0.5 - 0.5*proj_geom['DetectorCount']) * detu
for i in range(proj_geom['DetectorCount']):
yield ((detb + i * detu - ray, detb + i * detu),
(detb + (i - 0.5) * detu - ray, detb + (i - 0.5) * detu),
(detb + (i + 0.5) * detu - ray, detb + (i + 0.5) * detu))
def gen_lines(proj_geom):
g = { 'fanflat': gen_lines_fanflat,
'fanflat_vec': gen_lines_fanflat_vec,
'parallel': gen_lines_parallel,
'parallel_vec': gen_lines_parallel_vec }
for l in g[proj_geom['type']](proj_geom):
yield l
range2d = ( 8, 64 )
def gen_random_geometry_fanflat():
if not NONUNITDET:
w = 1.0
else:
w = 0.6 + 0.8 * np.random.random()
pg = astra.create_proj_geom('fanflat', w, np.random.randint(*range2d), np.linspace(0, 2*np.pi, np.random.randint(*range2d), endpoint=False), 256 * (0.5 + np.random.random()), 256 * np.random.random())
return pg
def gen_random_geometry_parallel():
if not NONUNITDET:
w = 1.0
else:
w = 0.8 + 0.4 * np.random.random()
pg = astra.create_proj_geom('parallel', w, np.random.randint(*range2d), np.linspace(0, 2*np.pi, np.random.randint(*range2d), endpoint=False))
return pg
def gen_random_geometry_fanflat_vec():
Vectors = np.zeros([16,6])
# We assume constant detector width in these tests
if not NONUNITDET:
w = 1.0
else:
w = 0.6 + 0.8 * np.random.random()
for i in range(Vectors.shape[0]):
angle1 = 2*np.pi*np.random.random()
if OBLIQUE:
angle2 = angle1 + 0.5 * np.random.random()
else:
angle2 = angle1
dist1 = 256 * (0.5 + np.random.random())
detc = 10 * np.random.random(size=2)
detu = [ math.cos(angle1) * w, math.sin(angle1) * w ]
src = [ math.sin(angle2) * dist1, -math.cos(angle2) * dist1 ]
Vectors[i, :] = [ src[0], src[1], detc[0], detc[1], detu[0], detu[1] ]
pg = astra.create_proj_geom('fanflat_vec', np.random.randint(*range2d), Vectors)
return pg
def gen_random_geometry_parallel_vec():
Vectors = np.zeros([16,6])
# We assume constant detector width in these tests
if not NONUNITDET:
w = 1.0
else:
w = 0.6 + 0.8 * np.random.random()
for i in range(Vectors.shape[0]):
l = 0.6 + 0.8 * np.random.random()
angle1 = 2*np.pi*np.random.random()
if OBLIQUE:
angle2 = angle1 + 0.5 * np.random.random()
else:
angle2 = angle1
detc = 10 * np.random.random(size=2)
detu = [ math.cos(angle1) * w, math.sin(angle1) * w ]
ray = [ math.sin(angle2) * l, -math.cos(angle2) * l ]
Vectors[i, :] = [ ray[0], ray[1], detc[0], detc[1], detu[0], detu[1] ]
pg = astra.create_proj_geom('parallel_vec', np.random.randint(*range2d), Vectors)
return pg
def proj_type_to_fan(t):
if t == 'cuda':
return t
else:
return t + '_fanflat'
def display_mismatch(data, sinogram, a):
pylab.gray()
pylab.imshow(data)
pylab.figure()
pylab.imshow(sinogram)
pylab.figure()
pylab.imshow(a)
pylab.figure()
pylab.imshow(sinogram-a)
pylab.show()
def display_mismatch_triple(data, sinogram, a, b, c):
pylab.gray()
pylab.imshow(data)
pylab.figure()
pylab.imshow(sinogram)
pylab.figure()
pylab.imshow(b)
pylab.figure()
pylab.imshow(a)
pylab.figure()
pylab.imshow(c)
pylab.figure()
pylab.imshow(sinogram-a)
pylab.figure()
pylab.imshow(c-sinogram)
pylab.show()
class Test2DKernel(unittest.TestCase):
def single_test(self, type, proj_type):
shape = np.random.randint(*range2d, size=2)
# these rectangles are biased, but that shouldn't matter
rect_min = [ np.random.randint(0, a) for a in shape ]
rect_max = [ np.random.randint(rect_min[i]+1, shape[i]+1) for i in range(len(shape))]
if FLEXVOL:
if not NONSQUARE:
pixsize = np.array([0.5, 0.5]) + np.random.random()
else:
pixsize = 0.5 + np.random.random(size=2)
origin = 10 * np.random.random(size=2)
else:
pixsize = (1.,1.)
origin = (0.,0.)
vg = astra.create_vol_geom(shape[1], shape[0],
origin[0] - 0.5 * shape[0] * pixsize[0],
origin[0] + 0.5 * shape[0] * pixsize[0],
origin[1] - 0.5 * shape[1] * pixsize[1],
origin[1] + 0.5 * shape[1] * pixsize[1])
if type == 'parallel':
pg = gen_random_geometry_parallel()
projector_id = astra.create_projector(proj_type, pg, vg)
elif type == 'parallel_vec':
pg = gen_random_geometry_parallel_vec()
projector_id = astra.create_projector(proj_type, pg, vg)
elif type == 'fanflat':
pg = gen_random_geometry_fanflat()
projector_id = astra.create_projector(proj_type_to_fan(proj_type), pg, vg)
elif type == 'fanflat_vec':
pg = gen_random_geometry_fanflat_vec()
projector_id = astra.create_projector(proj_type_to_fan(proj_type), pg, vg)
data = np.zeros((shape[1], shape[0]), dtype=np.float32)
data[rect_min[1]:rect_max[1],rect_min[0]:rect_max[0]] = 1
sinogram_id, sinogram = astra.create_sino(data, projector_id)
self.assertTrue(np.all(np.isfinite(sinogram)))
#print(pg)
#print(vg)
astra.data2d.delete(sinogram_id)
astra.projector.delete(projector_id)
# NB: Flipped y-axis here, since that is how astra interprets 2D volumes
xmin = origin[0] + (-0.5 * shape[0] + rect_min[0]) * pixsize[0]
xmax = origin[0] + (-0.5 * shape[0] + rect_max[0]) * pixsize[0]
ymin = origin[1] + (+0.5 * shape[1] - rect_max[1]) * pixsize[1]
ymax = origin[1] + (+0.5 * shape[1] - rect_min[1]) * pixsize[1]
if proj_type == 'line':
a = np.zeros(np.prod(astra.functions.geom_size(pg)), dtype=np.float32)
b = np.zeros(np.prod(astra.functions.geom_size(pg)), dtype=np.float32)
c = np.zeros(np.prod(astra.functions.geom_size(pg)), dtype=np.float32)
for i, (center, edge1, edge2) in enumerate(gen_lines(pg)):
(src, det) = center
# We compute line intersections with slightly bigger (cw) and
# smaller (aw) rectangles, and see if the kernel falls
# between these two values.
(aw,bw,cw) = intersect_line_rectangle_interval(src, det,
xmin, xmax, ymin, ymax,
1e-3)
a[i] = aw
b[i] = bw
c[i] = cw
a = a.reshape(astra.functions.geom_size(pg))
b = b.reshape(astra.functions.geom_size(pg))
c = c.reshape(astra.functions.geom_size(pg))
if not np.all(np.isfinite(a)):
raise RuntimeError("Invalid value in reference sinogram")
if not np.all(np.isfinite(b)):
raise RuntimeError("Invalid value in reference sinogram")
if not np.all(np.isfinite(c)):
raise RuntimeError("Invalid value in reference sinogram")
self.assertTrue(np.all(np.isfinite(sinogram)))
# Check if sinogram lies between a and c
y = np.min(sinogram-a)
z = np.min(c-sinogram)
if DISPLAY and (z < 0 or y < 0):
display_mismatch_triple(data, sinogram, a, b, c)
self.assertFalse(z < 0 or y < 0)
elif proj_type == 'linear' or proj_type == 'cuda':
a = np.zeros(np.prod(astra.functions.geom_size(pg)), dtype=np.float32)
for i, (center, edge1, edge2) in enumerate(gen_lines(pg)):
(src, det) = center
(xd, yd) = det - src
l = 0.0
if np.abs(xd) > np.abs(yd): # horizontal ray
length = math.sqrt(1.0 + abs(yd/xd)**2) * pixsize[0]
y_seg = (ymin, ymax)
for j in range(rect_min[0], rect_max[0]):
x = origin[0] + (-0.5 * shape[0] + j + 0.5) * pixsize[0]
w = intersect_line_vertical_segment_linear(center[0], center[1], x, y_seg, pixsize[1])
# limited interpolation precision with cuda
if CUDA_8BIT_LINEAR and proj_type == 'cuda':
w = np.round(w * 256.0) / 256.0
l += w * length
else:
length = math.sqrt(1.0 + abs(xd/yd)**2) * pixsize[1]
x_seg = (xmin, xmax)
for j in range(rect_min[1], rect_max[1]):
y = origin[1] + (+0.5 * shape[1] - j - 0.5) * pixsize[1]
w = intersect_line_horizontal_segment_linear(center[0], center[1], y, x_seg, pixsize[0])
# limited interpolation precision with cuda
if CUDA_8BIT_LINEAR and proj_type == 'cuda':
w = np.round(w * 256.0) / 256.0
l += w * length
a[i] = l
a = a.reshape(astra.functions.geom_size(pg))
if not np.all(np.isfinite(a)):
raise RuntimeError("Invalid value in reference sinogram")
x = np.max(np.abs(sinogram-a))
TOL = 2e-3 if proj_type != 'cuda' else CUDA_TOL
if DISPLAY and x > TOL:
display_mismatch(data, sinogram, a)
self.assertFalse(x > TOL)
elif proj_type == 'distance_driven' and 'par' in type:
a = np.zeros(np.prod(astra.functions.geom_size(pg)), dtype=np.float32)
for i, (center, edge1, edge2) in enumerate(gen_lines(pg)):
(src, det) = center
try:
detweight = pg['DetectorWidth']
except KeyError:
detweight = effective_detweight(src, det, pg['Vectors'][i//pg['DetectorCount'],4:6])
(xd, yd) = det - src
l = 0.0
if np.abs(xd) > np.abs(yd): # horizontal ray
y_seg = (ymin, ymax)
for j in range(rect_min[0], rect_max[0]):
x = origin[0] + (-0.5 * shape[0] + j + 0.5) * pixsize[0]
l += intersect_ray_vertical_segment(edge1, edge2, x, y_seg) * pixsize[0] / detweight
else:
x_seg = (xmin, xmax)
for j in range(rect_min[1], rect_max[1]):
y = origin[1] + (+0.5 * shape[1] - j - 0.5) * pixsize[1]
l += intersect_ray_horizontal_segment(edge1, edge2, y, x_seg) * pixsize[1] / detweight
a[i] = l
a = a.reshape(astra.functions.geom_size(pg))
if not np.all(np.isfinite(a)):
raise RuntimeError("Invalid value in reference sinogram")
x = np.max(np.abs(sinogram-a))
TOL = 2e-3
if DISPLAY and x > TOL:
display_mismatch(data, sinogram, a)
self.assertFalse(x > TOL)
elif proj_type == 'strip' and 'fan' in type:
a = np.zeros(np.prod(astra.functions.geom_size(pg)), dtype=np.float32)
for i, (center, edge1, edge2) in enumerate(gen_lines(pg)):
(src, det) = center
detweight = effective_detweight(src, det, edge2[1] - edge1[1])
det_dist = np.linalg.norm(src-det, ord=2)
l = 0.0
for j in range(rect_min[0], rect_max[0]):
xmin = origin[0] + (-0.5 * shape[0] + j) * pixsize[0]
xmax = origin[0] + (-0.5 * shape[0] + j + 1) * pixsize[0]
xcen = 0.5 * (xmin + xmax)
for k in range(rect_min[1], rect_max[1]):
ymin = origin[1] + (+0.5 * shape[1] - k - 1) * pixsize[1]
ymax = origin[1] + (+0.5 * shape[1] - k) * pixsize[1]
ycen = 0.5 * (ymin + ymax)
scale = det_dist / (np.linalg.norm( src - np.array((xcen,ycen)), ord=2 ) * detweight)
w = intersect_ray_rect(edge1, edge2, xmin, xmax, ymin, ymax)
l += w * scale
a[i] = l
a = a.reshape(astra.functions.geom_size(pg))
if not np.all(np.isfinite(a)):
raise RuntimeError("Invalid value in reference sinogram")
x = np.max(np.abs(sinogram-a))
# BUG: Known bug in fan/strip code around 45 degree projections causing larger errors than desirable
TOL = 4e-2
if DISPLAY and x > TOL:
display_mismatch(data, sinogram, a)
self.assertFalse(x > TOL)
elif proj_type == 'strip':
a = np.zeros(np.prod(astra.functions.geom_size(pg)), dtype=np.float32)
for i, (center, edge1, edge2) in enumerate(gen_lines(pg)):
(src, det) = center
try:
detweight = pg['DetectorWidth']
except KeyError:
detweight = effective_detweight(src, det, pg['Vectors'][i//pg['DetectorCount'],4:6])
a[i] = intersect_ray_rect(edge1, edge2, xmin, xmax, ymin, ymax) / detweight
a = a.reshape(astra.functions.geom_size(pg))
if not np.all(np.isfinite(a)):
raise RuntimeError("Invalid value in reference sinogram")
x = np.max(np.abs(sinogram-a))
TOL = 8e-3
if DISPLAY and x > TOL:
display_mismatch(data, sinogram, a)
self.assertFalse(x > TOL)
else:
raise RuntimeError("Unsupported projector")
def single_test_adjoint(self, type, proj_type):
shape = np.random.randint(*range2d, size=2)
if FLEXVOL:
if not NONSQUARE:
pixsize = np.array([0.5, 0.5]) + np.random.random()
else:
pixsize = 0.5 + np.random.random(size=2)
origin = 10 * np.random.random(size=2)
else:
pixsize = (1.,1.)
origin = (0.,0.)
vg = astra.create_vol_geom(shape[1], shape[0],
origin[0] - 0.5 * shape[0] * pixsize[0],
origin[0] + 0.5 * shape[0] * pixsize[0],
origin[1] - 0.5 * shape[1] * pixsize[1],
origin[1] + 0.5 * shape[1] * pixsize[1])
if type == 'parallel':
pg = gen_random_geometry_parallel()
projector_id = astra.create_projector(proj_type, pg, vg)
elif type == 'parallel_vec':
pg = gen_random_geometry_parallel_vec()
projector_id = astra.create_projector(proj_type, pg, vg)
elif type == 'fanflat':
pg = gen_random_geometry_fanflat()
projector_id = astra.create_projector(proj_type_to_fan(proj_type), pg, vg)
elif type == 'fanflat_vec':
pg = gen_random_geometry_fanflat_vec()
projector_id = astra.create_projector(proj_type_to_fan(proj_type), pg, vg)
for i in range(5):
X = np.random.random((shape[1], shape[0]))
Y = np.random.random(astra.geom_size(pg))
sinogram_id, fX = astra.create_sino(X, projector_id)
bp_id, fTY = astra.create_backprojection(Y, projector_id)
astra.data2d.delete(sinogram_id)
astra.data2d.delete(bp_id)
da = np.dot(fX.ravel(), Y.ravel())
db = np.dot(X.ravel(), fTY.ravel())
m = np.abs(da - db)
TOL = 1e-3 if 'cuda' not in proj_type else 1e-1
if m / da >= TOL:
print(vg)
print(pg)
print(m/da, da/db, da, db)
self.assertTrue(m / da < TOL)
astra.projector.delete(projector_id)
def multi_test(self, type, proj_type):
np.random.seed(seed)
for _ in range(nloops):
self.single_test(type, proj_type)
def multi_test_adjoint(self, type, proj_type):
np.random.seed(seed)
for _ in range(nloops):
self.single_test_adjoint(type, proj_type)
__combinations = { 'parallel': [ 'line', 'linear', 'distance_driven', 'strip', 'cuda' ],
'parallel_vec': [ 'line', 'linear', 'distance_driven', 'strip', 'cuda' ],
'fanflat': [ 'line', 'strip', 'cuda' ],
'fanflat_vec': [ 'line', 'cuda' ] }
for k, l in __combinations.items():
for v in l:
def f(k,v):
return lambda self: self.multi_test(k, v)
def f_adj(k,v):
return lambda self: self.multi_test_adjoint(k, v)
setattr(Test2DKernel, 'test_' + k + '_' + v, f(k,v))
setattr(Test2DKernel, 'test_' + k + '_' + v + '_adjoint', f_adj(k,v))
if __name__ == '__main__':
unittest.main()
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