diff --git a/lib/matplotlib/testing/compare.py b/lib/matplotlib/testing/compare.py index 665e055f123a..4afb3c6ecea2 100644 --- a/lib/matplotlib/testing/compare.py +++ b/lib/matplotlib/testing/compare.py @@ -371,6 +371,16 @@ def calculate_rms(expected_image, actual_image): # 16-bit depth, as Pillow converts these to RGB incorrectly. +def _load_image(path): + img = Image.open(path) + # In an RGBA image, if the smallest value in the alpha channel is 255, all + # values in it must be 255, meaning that the image is opaque. If so, + # discard the alpha channel so that it may compare equal to an RGB image. + if img.mode != "RGBA" or img.getextrema()[3][0] == 255: + img = img.convert("RGB") + return np.asarray(img) + + def compare_images(expected, actual, tol, in_decorator=False): """ Compare two "image" files checking differences within a tolerance. @@ -435,9 +445,9 @@ def compare_images(expected, actual, tol, in_decorator=False): actual = convert(actual, cache=True) expected = convert(expected, cache=True) - # open the image files and remove the alpha channel (if it exists) - expected_image = np.asarray(Image.open(expected).convert("RGB")) - actual_image = np.asarray(Image.open(actual).convert("RGB")) + # open the image files + expected_image = _load_image(expected) + actual_image = _load_image(actual) actual_image, expected_image = crop_to_same( actual, actual_image, expected, expected_image) @@ -486,9 +496,8 @@ def save_diff_image(expected, actual, output): output : str File path to save difference image to. """ - # Drop alpha channels, similarly to compare_images. - expected_image = np.asarray(Image.open(expected).convert("RGB")) - actual_image = np.asarray(Image.open(actual).convert("RGB")) + expected_image = _load_image(expected) + actual_image = _load_image(actual) actual_image, expected_image = crop_to_same( actual, actual_image, expected, expected_image) expected_image = np.array(expected_image).astype(float) diff --git a/lib/matplotlib/tests/baseline_images/test_bbox_tight/bbox_inches_tight_suptile_legend.svg b/lib/matplotlib/tests/baseline_images/test_bbox_tight/bbox_inches_tight_suptile_legend.svg index c99489ca7dfb..5cf932d60cb7 100644 --- a/lib/matplotlib/tests/baseline_images/test_bbox_tight/bbox_inches_tight_suptile_legend.svg +++ b/lib/matplotlib/tests/baseline_images/test_bbox_tight/bbox_inches_tight_suptile_legend.svg @@ -1,21 +1,32 @@ - -