Merged in bugfix/RAM-3906_0_crop (pull request jrkerns#438)

RAM-3906 Allow cropping of 0 pixels.

Approved-by: Randy Taylor
Approved-by: Hasan Ammar

docs/source/changelog.rst

@@ -36,6 +36,11 @@ ACR MRI
   the full circle of the phantom. The algorithm no longer relies on this assumption and
   is robust to these air gaps for the geometric distortion analysis.
 
+Core
+^^^^
+
+* Performing :meth:`~pylinac.core.image.BaseImage.crop` on an image now allows for a ``pixels`` input of 0. This allows for a no-op crop.
+
 v 3.26.0
 --------
 

pylinac/core/image.py

@@ -640,8 +640,12 @@ def crop(
         edges : tuple
             Which edges to remove from. Can be any combination of the four edges.
         """
-        if pixels <= 0:
+        if pixels < 0:
             raise ValueError("Pixels to remove must be a positive number")
+        if pixels == 0:
+            # using 0 will cause an error in numpy slicing
+            # we also want to be able to handle a no-op
+            return
         if "top" in edges:
             self.array = self.array[pixels:, :]
         if "bottom" in edges:

pyproject.toml

@@ -59,6 +59,7 @@ dev = [
     "sphinx-copybutton",
     "pre-commit",
     "hatch",
+    "parameterized",
 ]
 docs = [
     "sphinx",

tests_basic/core/test_image.py

@@ -14,6 +14,7 @@
 import PIL.Image
 import pydicom
 from numpy.testing import assert_array_almost_equal
+from parameterized import parameterized
 from pydicom.uid import UID
 
 from pylinac import settings
@@ -342,9 +343,9 @@ def setUp(self):
         array = np.arange(42).reshape(6, 7)
         self.arr = image.load(array)
 
-    def test_crop(self):
+    @parameterized.expand([15, 0])
+    def test_crop(self, crop):
         """Remove the edges from a pixel array."""
-        crop = 15
         orig_shape = self.img.shape
         orig_dpi = self.img.dpi
         self.img.crop(crop)
@@ -356,7 +357,7 @@ def test_crop(self):
 
     def test_crop_must_be_positive(self):
         """Crop must be manifestly positive"""
-        crop = 0
+        crop = -1
         with self.assertRaises(ValueError):
             self.img.crop(crop)
 

tests_basic/test_picketfence.py

@@ -479,6 +479,7 @@ class PFTestMixin(CloudFileMixin):
     abs_median_error = 0
     sag_adjustment = 0
     invert = False
+    crop_mm: int = 3
     passes = True
     log = None
     mean_picket_spacing = 15
@@ -496,7 +497,9 @@ def get_logfile(cls):
 
     @classmethod
     def setUpClass(cls):
-        cls.pf = PicketFence(cls.get_filename(), log=cls.get_logfile())
+        cls.pf = PicketFence(
+            cls.get_filename(), log=cls.get_logfile(), crop_mm=cls.crop_mm
+        )
         if cls.pass_num_pickets:
             cls.pf.analyze(
                 sag_adjustment=cls.sag_adjustment,
@@ -581,6 +584,7 @@ class PerfectSimulation(PFTestMixin, TestCase):
     abs_median_error = 0
     num_pickets = 5
     mean_picket_spacing = 20
+    crop_mm = 0
 
 
 class Rotated2Simulation(PFTestMixin, TestCase):