def testImportExport(self):
"Testing if images can be imported to and from numeric arrays."
imp = vtkImageImportFromArray()
exp = vtkImageExportToArray()
idiff = vtk.vtkImageDifference()
img_dir = Testing.getAbsImagePath("")
for i in glob.glob(os.path.join(img_dir, "*.png")):
# Putting the reader outside the loop causes bad problems.
reader = vtk.vtkPNGReader()
reader.SetFileName(i)
reader.Update()
# convert the image to a Numeric Array and convert it back
# to an image data.
exp.SetInputConnection(reader.GetOutputPort())
imp.SetArray(exp.GetArray())
# ensure there is no difference between orig image and the
# one we converted and un-converted.
idiff.SetInputConnection(imp.GetOutputPort())
idiff.SetImage(reader.GetOutput())
idiff.Update()
err = idiff.GetThresholdedError()
msg = "Test failed on image %s, with threshold "\
"error: %d"%(i, err)
self.assertEqual(err, 0.0, msg)
def testImportExport(self):
"Testing if images can be imported to and from numeric arrays."
imp = vtkImageImportFromArray()
exp = vtkImageExportToArray()
idiff = vtk.vtkImageDifference()
img_dir = Testing.getAbsImagePath("")
for i in glob.glob(os.path.join(img_dir, "*.png")):
# Putting the reader outside the loop causes bad problems.
reader = vtk.vtkPNGReader()
reader.SetFileName(i)
reader.Update()
# convert the image to a Numeric Array and convert it back
# to an image data.
exp.SetInputConnection(reader.GetOutputPort())
imp.SetArray(exp.GetArray())
# ensure there is no difference between orig image and the
# one we converted and un-converted.
idiff.SetInputConnection(imp.GetOutputPort())
idiff.SetImage(reader.GetOutput())
idiff.Update()
err = idiff.GetThresholdedError()
msg = "Test failed on image %s, with threshold "\
"error: %d"%(i, err)
self.assertEqual(err, 0.0, msg)
def __init__(self, module_manager):
SimpleVTKClassModuleBase.__init__(
self, module_manager,
vtk.vtkImageDifference(), 'Processing.',
('vtkImageData', 'vtkImageData'), ('vtkImageData',),
replaceDoc=True,
inputFunctions=None, outputFunctions=None)
def __init__(self, module_manager):
SimpleVTKClassModuleBase.__init__(self,
module_manager,
vtk.vtkImageDifference(),
'Processing.',
('vtkImageData', 'vtkImageData'),
('vtkImageData', ),
replaceDoc=True,
inputFunctions=None,
outputFunctions=None)
def compare_png_images(self,
image1_filename,
image2_filename,
threshold=16,
allow_shift=False):
"""Compare two PNG images on disc. No two pixels may differ with more
than the default threshold.
"""
import vtk
r1 = vtk.vtkPNGReader()
r1.SetFileName(image1_filename)
r1.Update()
r2 = vtk.vtkPNGReader()
r2.SetFileName(image2_filename)
r2.Update()
# there's a bug in VTK 5.0.1 where input images of unequal size
# (depending on which input is larger) will cause a segfault
# see http://www.vtk.org/Bug/bug.php?op=show&bugid=3586
# se we check for that situation and bail if it's the case
if r1.GetOutput().GetDimensions() != r2.GetOutput().GetDimensions():
em = 'Input images %s and %s are not of equal size.' % \
(image1_filename, image2_filename)
raise RuntimeError, em
# sometimes PNG files have an ALPHA component we have to chuck away
# do this for both images
ec1 = vtk.vtkImageExtractComponents()
ec1.SetComponents(0, 1, 2)
ec1.SetInput(r1.GetOutput())
ec2 = vtk.vtkImageExtractComponents()
ec2.SetComponents(0, 1, 2)
ec2.SetInput(r2.GetOutput())
idiff = vtk.vtkImageDifference()
idiff.SetThreshold(threshold)
if allow_shift:
idiff.AllowShiftOn()
else:
idiff.AllowShiftOff()
idiff.SetImage(ec1.GetOutput())
idiff.SetInputConnection(ec2.GetOutputPort())
idiff.Update()
return idiff.GetThresholdedError()
def compare_png_images(self, image1_filename, image2_filename,
threshold=16, allow_shift=False):
"""Compare two PNG images on disc. No two pixels may differ with more
than the default threshold.
"""
import vtk
r1 = vtk.vtkPNGReader()
r1.SetFileName(image1_filename)
r1.Update()
r2 = vtk.vtkPNGReader()
r2.SetFileName(image2_filename)
r2.Update()
# there's a bug in VTK 5.0.1 where input images of unequal size
# (depending on which input is larger) will cause a segfault
# see http://www.vtk.org/Bug/bug.php?op=show&bugid=3586
# se we check for that situation and bail if it's the case
if r1.GetOutput().GetDimensions() != r2.GetOutput().GetDimensions():
em = 'Input images %s and %s are not of equal size.' % \
(image1_filename, image2_filename)
raise RuntimeError, em
# sometimes PNG files have an ALPHA component we have to chuck away
# do this for both images
ec1 = vtk.vtkImageExtractComponents()
ec1.SetComponents(0,1,2)
ec1.SetInput(r1.GetOutput())
ec2 = vtk.vtkImageExtractComponents()
ec2.SetComponents(0,1,2)
ec2.SetInput(r2.GetOutput())
idiff = vtk.vtkImageDifference()
idiff.SetThreshold(threshold)
if allow_shift:
idiff.AllowShiftOn()
else:
idiff.AllowShiftOff()
idiff.SetImage(ec1.GetOutput())
idiff.SetInputConnection(ec2.GetOutputPort())
idiff.Update()
return idiff.GetThresholdedError()
def compare_thumbnails(prev, next):
#vtkImageDifference assumes RGB, so strip alpha
def removeAlpha(file):
freader = vtk.vtkPNGReader()
freader.SetFileName(file)
removealpha = vtk.vtkImageExtractComponents()
removealpha.SetComponents(0,1,2)
removealpha.SetInputConnection(freader.GetOutputPort())
removealpha.Update()
return removealpha.GetOutput()
#do the image comparison
a = removeAlpha(prev)
b = removeAlpha(next)
idiff = vtk.vtkImageDifference()
idiff.SetInput(a)
idiff.SetImage(b)
idiff.Update()
return idiff.GetThresholdedError()
def test_example(tmp_path):
os.chdir(tmp_path)
assets = Path(__file__).parent / 'assets'
for f in [
"example.xyz", "example.settings", "example.commands",
"example.iso"
]:
shutil.copy(assets / f, f)
ref_reader = vtk.vtkPNGReader()
ref_reader.SetFileName(str(assets / "example.png"))
ref_reader.Update()
ref_img = vtk.vtkImageExtractComponents()
ref_img.SetComponents(0, 1, 2)
ref_img.SetInputConnection(ref_reader.GetOutputPort())
ref_img.Update()
p = subprocess.Popen([
'dap', '-e', 'read example.settings', '-e', 'read example.commands',
'-e', 'view -dir 1 0.1 0.2 0 0 1', 'example.xyz'
],
stdin=subprocess.PIPE,
stdout=subprocess.PIPE,
stderr=subprocess.PIPE)
out, err = p.communicate('snapshot test.png\nexit\n'.encode())
assert p.returncode == 0
test_reader = vtk.vtkPNGReader()
test_reader.SetFileName("test.png")
test_reader.Update()
test_img = vtk.vtkImageExtractComponents()
test_img.SetComponents(0, 1, 2)
test_img.SetInputConnection(test_reader.GetOutputPort())
test_img.Update()
idiff = vtk.vtkImageDifference()
# idiff.SetThreshold(1)
idiff.AllowShiftOff()
idiff.SetImageData(ref_img.GetOutput())
idiff.SetInputConnection(test_img.GetOutputPort())
idiff.Update()
# print("thresh error", idiff.GetThresholdedError())
assert idiff.GetError() < 1.0e-10
def compare_thumbnails(prev, next):
#vtkImageDifference assumes RGB, so strip alpha
def removeAlpha(file):
freader = vtk.vtkPNGReader()
freader.SetFileName(file)
removealpha = vtk.vtkImageExtractComponents()
removealpha.SetComponents(0, 1, 2)
removealpha.SetInputConnection(freader.GetOutputPort())
removealpha.Update()
return removealpha.GetOutput()
#do the image comparison
a = removeAlpha(prev)
b = removeAlpha(next)
idiff = vtk.vtkImageDifference()
idiff.SetInput(a)
idiff.SetImage(b)
idiff.Update()
return idiff.GetThresholdedError()
def vtkRegressionTestImage( renWin ):
"""vtkRegressionTestImage(renWin) -- produce regression image for window
This function writes out a regression .png file for a vtkWindow.
Does anyone involved in testing care to elaborate?
"""
imageIndex=-1;
for i in range(0, len(sys.argv)):
if sys.argv[i] == '-V' and i < len(sys.argv)-1:
imageIndex = i+1
if imageIndex != -1:
fname = os.path.join(vtkGetDataRoot(), sys.argv[imageIndex])
rt_w2if = vtk.vtkWindowToImageFilter()
rt_w2if.SetInput(renWin)
if os.path.isfile(fname):
pass
else:
rt_pngw = vtk.vtkPNGWriter()
rt_pngw.SetFileName(fname)
rt_pngw.SetInput(rt_w2if.GetOutput())
rt_pngw.Write()
rt_pngw = None
rt_png = vtk.vtkPNGReader()
rt_png.SetFileName(fname)
rt_id = vtk.vtkImageDifference()
rt_id.SetInput(rt_w2if.GetOutput())
rt_id.SetImage(rt_png.GetOutput())
rt_id.Update()
if rt_id.GetThresholdedError() <= 10:
return 1
else:
sys.stderr.write('Failed image test: %f\n'
% rt_id.GetThresholdedError())
return 0
return 2
def vtkRegressionTestImage( renWin ):
"""vtkRegressionTestImage(renWin) -- produce regression image for window
This function writes out a regression .png file for a vtkWindow.
Does anyone involved in testing care to elaborate?
"""
imageIndex=-1;
for i in range(0, len(sys.argv)):
if sys.argv[i] == '-V' and i < len(sys.argv)-1:
imageIndex = i+1
if imageIndex != -1:
fname = os.path.join(vtkGetDataRoot(), sys.argv[imageIndex])
rt_w2if = vtk.vtkWindowToImageFilter()
rt_w2if.SetInput(renWin)
if os.path.isfile(fname):
pass
else:
rt_pngw = vtk.vtkPNGWriter()
rt_pngw.SetFileName(fname)
rt_pngw.SetInputConnection(rt_w2if.GetOutputPort())
rt_pngw.Write()
rt_pngw = None
rt_png = vtk.vtkPNGReader()
rt_png.SetFileName(fname)
rt_id = vtk.vtkImageDifference()
rt_id.SetInputConnection(rt_w2if.GetOutputPort())
rt_id.SetImageConnection(rt_png.GetOutputPort())
rt_id.Update()
if rt_id.GetThresholdedError() <= 10:
return 1
else:
sys.stderr.write('Failed image test: %f\n'
% rt_id.GetThresholdedError())
return 0
return 2
def compare_screenshots(png0, png1, threshold):
# load the two input images
img0 = vtk.vtkPNGReader()
img0.SetFileName(png0)
img0.Update()
img1 = vtk.vtkPNGReader()
img1.SetFileName(png1)
img1.Update()
# compare the two images
imdiff = vtk.vtkImageDifference()
imdiff.SetInputConnection(img0.GetOutputPort())
imdiff.SetImageConnection(img1.GetOutputPort())
imdiff.Update()
err = round(imdiff.GetThresholdedError(), 3)
if err > threshold:
return (False, err)
return (True, err)
def compareImageWithSavedImage(src_img, img_fname, threshold=10):
"""Compares a source image (src_img, which is a vtkImageData) with
the saved image file whose name is given in the second argument.
If the image file does not exist the image is generated and
stored. If not the source image is compared to that of the
figure. This function also handles multiple images and finds the
best matching image.
"""
global _NO_IMAGE
if _NO_IMAGE:
return
f_base, f_ext = os.path.splitext(img_fname)
if not os.path.isfile(img_fname):
# generate the image
pngw = vtk.vtkPNGWriter()
pngw.SetFileName(_getTempImagePath(img_fname))
pngw.SetInputConnection(src_img.GetOutputPort())
pngw.Write()
_printCDashImageNotFoundError(img_fname)
msg = "Missing baseline image: " + img_fname + "\nTest image created: " + _getTempImagePath(img_fname)
sys.tracebacklimit = 0
raise RuntimeError(msg)
pngr = vtk.vtkPNGReader()
pngr.SetFileName(img_fname)
pngr.Update()
idiff = vtk.vtkImageDifference()
idiff.SetInputConnection(src_img.GetOutputPort())
idiff.SetImageConnection(pngr.GetOutputPort())
idiff.Update()
min_err = idiff.GetThresholdedError()
img_err = min_err
err_index = 0
count = 0
if min_err > threshold:
count = 1
test_failed = 1
err_index = -1
while 1: # keep trying images till we get the best match.
new_fname = f_base + "_%d.png"%count
if not os.path.exists(new_fname):
# no other image exists.
break
# since file exists check if it matches.
pngr.SetFileName(new_fname)
pngr.Update()
idiff.Update()
alt_err = idiff.GetThresholdedError()
if alt_err < threshold:
# matched,
err_index = count
test_failed = 0
min_err = alt_err
img_err = alt_err
break
else:
if alt_err < min_err:
# image is a better match.
err_index = count
min_err = alt_err
img_err = alt_err
count = count + 1
# closes while loop.
if test_failed:
_handleFailedImage(idiff, pngr, img_fname)
# Print for CDash.
_printCDashImageError(img_err, err_index, f_base)
msg = "Failed image test: %f\n"%idiff.GetThresholdedError()
sys.tracebacklimit = 0
raise RuntimeError(msg)
# output the image error even if a test passed
_printCDashImageSuccess(img_err, err_index)
def image_compare(testImage, baselineImage):
imageDiff = vtk.vtkImageDifference()
imageDiff.SetInputData(testImage)
imageDiff.SetImageData(baselineImage)
imageDiff.Update()
return (imageDiff.GetThresholdedError(), imageDiff.GetOutput())
def image_compare(testImage, baselineImage):
imageDiff = vtk.vtkImageDifference()
imageDiff.SetInputData(testImage)
imageDiff.SetImageData(baselineImage)
imageDiff.Update()
return (imageDiff.GetThresholdedError(), imageDiff.GetOutput())
def compareImageWithSavedImage(src_img, img_fname, threshold=10):
"""Compares a source image (src_img, which is a vtkImageData) with
the saved image file whose name is given in the second argument.
If the image file does not exist the image is generated and
stored. If not the source image is compared to that of the
figure. This function also handles multiple images and finds the
best matching image.
"""
global _NO_IMAGE
if _NO_IMAGE:
return
f_base, f_ext = os.path.splitext(img_fname)
if not os.path.isfile(img_fname):
# generate the image
pngw = vtk.vtkPNGWriter()
pngw.SetFileName(_getTempImagePath(img_fname))
pngw.SetInput(src_img)
pngw.Write()
return
pngr = vtk.vtkPNGReader()
pngr.SetFileName(img_fname)
idiff = vtk.vtkImageDifference()
idiff.SetInput(src_img)
idiff.SetImage(pngr.GetOutput())
idiff.Update()
min_err = idiff.GetThresholdedError()
img_err = min_err
best_img = img_fname
err_index = 0
count = 0
if min_err > threshold:
count = 1
test_failed = 1
err_index = -1
while 1: # keep trying images till we get the best match.
new_fname = f_base + "_%d.png"%count
if not os.path.exists(new_fname):
# no other image exists.
break
# since file exists check if it matches.
pngr.SetFileName(new_fname)
pngr.Update()
idiff.Update()
alt_err = idiff.GetThresholdedError()
if alt_err < threshold:
# matched,
err_index = count
test_failed = 0
min_err = alt_err
img_err = alt_err
best_img = new_fname
break
else:
if alt_err < min_err:
# image is a better match.
err_index = count
min_err = alt_err
img_err = alt_err
best_img = new_fname
count = count + 1
# closes while loop.
if test_failed:
_handleFailedImage(idiff, pngr, best_img)
# Print for Dart.
_printDartImageError(img_err, err_index, f_base)
msg = "Failed image test: %f\n"%idiff.GetThresholdedError()
raise AssertionError, msg
# output the image error even if a test passed
_printDartImageSuccess(img_err, err_index)
def compare_images(im1, im2, threshold=1, use_vtk=True):
"""Compare two different images of the same size.
Parameters
----------
im1 : filename, np.ndarray, vtkRenderWindow, or vtkImageData
Render window, numpy array representing the output of a render
window, or ``vtkImageData``
im2 : filename, np.ndarray, vtkRenderWindow, or vtkImageData
Render window, numpy array representing the output of a render
window, or ``vtkImageData``
threshold : int
Threshold tolerance for pixel differences. This should be
greater than 0, otherwise it will always return an error, even
on identical images.
use_vtk : bool
When disabled, computes the mean pixel error over the entire
image using numpy. The difference between pixel is calculated
for each RGB channel, summed, and then divided by the number
of pixels. This is faster than using
``vtk.vtkImageDifference`` but potentially less accurate.
Returns
-------
error : float
Total error between the images if using ``use_vtk=True``, and
the mean pixel error when ``use_vtk=False``.
Examples
--------
Compare two active plotters
>>> import pyvista
>>> pl1 = pyvista.Plotter()
>>> _ = pl1.add_mesh(pyvista.Sphere(), smooth_shading=True)
>>> pl2 = pyvista.Plotter()
>>> _ = pl2.add_mesh(pyvista.Sphere(), smooth_shading=False)
>>> pyvista.compare_images(pl1, pl2) # doctest:+SKIP
Compare two active plotters
>>> import pyvista
>>> img1 = pyvista.read('img1.png') # doctest:+SKIP
>>> img2 = pyvista.read('img2.png') # doctest:+SKIP
>>> pyvista.compare_images(img1, img2) # doctest:+SKIP
"""
from pyvista import wrap, UniformGrid, read, Plotter
def to_img(img):
if isinstance(img, UniformGrid): # pragma: no cover
return img
elif isinstance(img, vtk.vtkImageData):
return wrap(img)
elif isinstance(img, str):
return read(img)
elif isinstance(img, np.ndarray):
return wrap_image_array(img)
elif isinstance(img, Plotter):
if img._first_time: # must be rendered first else segfault
img._on_first_render_request()
img.render()
return image_from_window(img.ren_win, True, ignore_alpha=True)
else:
raise TypeError(
f'Unsupported data type {type(img)}. Should be '
'Either a np.ndarray, vtkRenderWindow, or vtkImageData')
im1 = remove_alpha(to_img(im1))
im2 = remove_alpha(to_img(im2))
if im1.GetDimensions() != im2.GetDimensions():
raise RuntimeError('Input images %s and %s are not of equal size.')
if use_vtk:
img_diff = vtk.vtkImageDifference()
img_diff.SetThreshold(threshold)
img_diff.SetInputData(im1)
img_diff.SetImageData(im2)
img_diff.AllowShiftOff() # vastly increases compute time when enabled
# img_diff.AveragingOff() # increases compute time
img_diff.Update()
return img_diff.GetError()
# otherwise, simply compute the mean pixel difference
diff = np.abs(im1.point_arrays[0] - im2.point_arrays[0])
return np.sum(diff) / im1.point_arrays[0].shape[0]
from vtk.util.vtkImageExportToArray import vtkImageExportToArray
from vtk.util.vtkImageImportFromArray import vtkImageImportFromArray
img1 = sys.argv[1]
img2 = sys.argv[2]
def setupReader(img):
rd = vtk.vtkPNGReader()
rd.SetFileName(img1)
rd.Update()
imp = vtkImageImportFromArray()
exp = vtkImageExportToArray()
exp.SetInputConnection(rd.GetOutputPort())
imp.SetArray(exp.GetArray())
return imp
rd1 = setupReader(img1)
rd2 = setupReader(img2)
idiff = vtk.vtkImageDifference()
idiff.SetInputConnection(rd2.GetOutputPort())
idiff.SetImageConnection(rd1.GetOutputPort())
idiff.Update()
err = idiff.GetThresholdedError()
print "Diff:",err
