mmcv/tests/test_image.py

312 lines
13 KiB
Python

import os
import os.path as osp
import tempfile
import cv2
import mmcv
import numpy as np
import pytest
from numpy.testing import assert_array_equal, assert_array_almost_equal
class TestImage(object):
@classmethod
def setup_class(cls):
# the test img resolution is 400x300
cls.img_path = osp.join(osp.dirname(__file__), 'data/color.jpg')
cls.gray_img_path = osp.join(
osp.dirname(__file__), 'data/grayscale.jpg')
cls.img = cv2.imread(cls.img_path)
def assert_img_equal(self, img, ref_img, ratio_thr=0.999):
assert img.shape == ref_img.shape
assert img.dtype == ref_img.dtype
area = ref_img.shape[0] * ref_img.shape[1]
diff = np.abs(img.astype('int32') - ref_img.astype('int32'))
assert np.sum(diff <= 1) / float(area) > ratio_thr
def test_imread(self):
img = mmcv.imread(self.img_path)
assert img.shape == (300, 400, 3)
img = mmcv.imread(self.img_path, 'grayscale')
assert img.shape == (300, 400)
img = mmcv.imread(self.gray_img_path)
assert img.shape == (300, 400, 3)
img = mmcv.imread(self.gray_img_path, 'unchanged')
assert img.shape == (300, 400)
img = mmcv.imread(img)
assert_array_equal(img, mmcv.imread(img))
with pytest.raises(TypeError):
mmcv.imread(1)
def test_imfrombytes(self):
with open(self.img_path, 'rb') as f:
img_bytes = f.read()
img = mmcv.imfrombytes(img_bytes)
assert img.shape == (300, 400, 3)
def test_imwrite(self):
img = mmcv.imread(self.img_path)
out_file = osp.join(tempfile.gettempdir(), 'mmcv_test.jpg')
mmcv.imwrite(img, out_file)
rewrite_img = mmcv.imread(out_file)
os.remove(out_file)
self.assert_img_equal(img, rewrite_img)
def test_bgr2gray(self):
in_img = np.random.rand(10, 10, 3).astype(np.float32)
out_img = mmcv.bgr2gray(in_img)
computed_gray = (in_img[:, :, 0] * 0.114 + in_img[:, :, 1] * 0.587 +
in_img[:, :, 2] * 0.299)
assert_array_almost_equal(out_img, computed_gray, decimal=4)
out_img_3d = mmcv.bgr2gray(in_img, True)
assert out_img_3d.shape == (10, 10, 1)
assert_array_almost_equal(out_img_3d[..., 0], out_img, decimal=4)
def test_gray2bgr(self):
in_img = np.random.rand(10, 10).astype(np.float32)
out_img = mmcv.gray2bgr(in_img)
assert out_img.shape == (10, 10, 3)
for i in range(3):
assert_array_almost_equal(out_img[..., i], in_img, decimal=4)
def test_bgr2rgb(self):
in_img = np.random.rand(10, 10, 3).astype(np.float32)
out_img = mmcv.bgr2rgb(in_img)
assert out_img.shape == in_img.shape
assert_array_equal(out_img[..., 0], in_img[..., 2])
assert_array_equal(out_img[..., 1], in_img[..., 1])
assert_array_equal(out_img[..., 2], in_img[..., 0])
def test_rgb2bgr(self):
in_img = np.random.rand(10, 10, 3).astype(np.float32)
out_img = mmcv.rgb2bgr(in_img)
assert out_img.shape == in_img.shape
assert_array_equal(out_img[..., 0], in_img[..., 2])
assert_array_equal(out_img[..., 1], in_img[..., 1])
assert_array_equal(out_img[..., 2], in_img[..., 0])
def test_bgr2hsv(self):
in_img = np.random.rand(10, 10, 3).astype(np.float32)
out_img = mmcv.bgr2hsv(in_img)
argmax = in_img.argmax(axis=2)
computed_hsv = np.empty_like(in_img, dtype=in_img.dtype)
for i in range(in_img.shape[0]):
for j in range(in_img.shape[1]):
b = in_img[i, j, 0]
g = in_img[i, j, 1]
r = in_img[i, j, 2]
v = max(r, g, b)
s = (v - min(r, g, b)) / v if v != 0 else 0
if argmax[i, j] == 0:
h = 240 + 60 * (r - g) / (v - min(r, g, b))
elif argmax[i, j] == 1:
h = 120 + 60 * (b - r) / (v - min(r, g, b))
else:
h = 60 * (g - b) / (v - min(r, g, b))
if h < 0:
h += 360
computed_hsv[i, j, :] = [h, s, v]
assert_array_almost_equal(out_img, computed_hsv, decimal=2)
def test_scale_size(self):
assert mmcv.scale_size((300, 200), 0.5) == (150, 100)
assert mmcv.scale_size((11, 22), 0.7) == (8, 15)
def test_imresize(self):
resized_img = mmcv.imresize(self.img, (1000, 600))
assert resized_img.shape == (600, 1000, 3)
resized_img, w_scale, h_scale = mmcv.imresize(self.img, (1000, 600),
True)
assert (resized_img.shape == (600, 1000, 3) and w_scale == 2.5
and h_scale == 2.0)
for mode in ['nearest', 'bilinear', 'bicubic', 'area', 'lanczos']:
resized_img = mmcv.imresize(
self.img, (1000, 600), interpolation=mode)
assert resized_img.shape == (600, 1000, 3)
def test_imresize_like(self):
a = np.zeros((100, 200, 3))
resized_img = mmcv.imresize_like(self.img, a)
assert resized_img.shape == (100, 200, 3)
def test_imrescale(self):
# rescale by a certain factor
resized_img = mmcv.imrescale(self.img, 1.5)
assert resized_img.shape == (450, 600, 3)
resized_img = mmcv.imrescale(self.img, 0.934)
assert resized_img.shape == (280, 374, 3)
# rescale by a certain max_size
# resize (400, 300) to (max_1000, max_600)
resized_img = mmcv.imrescale(self.img, (1000, 600))
assert resized_img.shape == (600, 800, 3)
resized_img, scale = mmcv.imrescale(
self.img, (1000, 600), return_scale=True)
assert resized_img.shape == (600, 800, 3) and scale == 2.0
# resize (400, 300) to (max_200, max_180)
resized_img = mmcv.imrescale(self.img, (180, 200))
assert resized_img.shape == (150, 200, 3)
resized_img, scale = mmcv.imrescale(
self.img, (180, 200), return_scale=True)
assert resized_img.shape == (150, 200, 3) and scale == 0.5
# test exceptions
with pytest.raises(ValueError):
mmcv.imrescale(self.img, -0.5)
with pytest.raises(TypeError):
mmcv.imrescale(self.img, [100, 100])
def test_limit_size(self):
# limit to 800
resized_img = mmcv.limit_size(self.img, 800)
assert resized_img.shape == (300, 400, 3)
resized_img, scale = mmcv.limit_size(self.img, 800, True)
assert resized_img.shape == (300, 400, 3) and scale == 1
# limit to 200
resized_img = mmcv.limit_size(self.img, 200)
assert resized_img.shape == (150, 200, 3)
resized_img, scale = mmcv.limit_size(self.img, 200, True)
assert resized_img.shape == (150, 200, 3) and scale == 0.5
# test with img rather than img path
img = mmcv.imread(self.img)
resized_img = mmcv.limit_size(img, 200)
assert resized_img.shape == (150, 200, 3)
resized_img, scale = mmcv.limit_size(img, 200, True)
assert resized_img.shape == (150, 200, 3) and scale == 0.5
def test_imflip(self):
# test horizontal flip (color image)
img = np.random.rand(80, 60, 3)
h, w, c = img.shape
flipped_img = mmcv.imflip(img)
assert flipped_img.shape == img.shape
for i in range(h):
for j in range(w):
for k in range(c):
assert flipped_img[i, j, k] == img[i, w - 1 - j, k]
# test vertical flip (color image)
flipped_img = mmcv.imflip(img, direction='vertical')
assert flipped_img.shape == img.shape
for i in range(h):
for j in range(w):
for k in range(c):
assert flipped_img[i, j, k] == img[h - 1 - i, j, k]
# test horizontal flip (grayscale image)
img = np.random.rand(80, 60)
h, w = img.shape
flipped_img = mmcv.imflip(img)
assert flipped_img.shape == img.shape
for i in range(h):
for j in range(w):
assert flipped_img[i, j] == img[i, w - 1 - j]
# test vertical flip (grayscale image)
flipped_img = mmcv.imflip(img, direction='vertical')
assert flipped_img.shape == img.shape
for i in range(h):
for j in range(w):
assert flipped_img[i, j] == img[h - 1 - i, j]
def test_imcrop(self):
# yapf: disable
bboxes = np.array([[100, 100, 199, 199], # center
[0, 0, 150, 100], # left-top corner
[250, 200, 399, 299], # right-bottom corner
[0, 100, 399, 199], # wide
[150, 0, 299, 299]]) # tall
# yapf: enable
# crop one bbox
patch = mmcv.imcrop(self.img, bboxes[0, :])
patches = mmcv.imcrop(self.img, bboxes[[0], :])
assert patch.shape == (100, 100, 3)
patch_path = osp.join(osp.dirname(__file__), 'data/patches')
ref_patch = np.load(patch_path + '/0.npy')
self.assert_img_equal(patch, ref_patch)
assert isinstance(patches, list) and len(patches) == 1
self.assert_img_equal(patches[0], ref_patch)
# crop with no scaling and padding
patches = mmcv.imcrop(self.img, bboxes)
assert len(patches) == bboxes.shape[0]
for i in range(len(patches)):
ref_patch = np.load(patch_path + '/{}.npy'.format(i))
self.assert_img_equal(patches[i], ref_patch)
# crop with scaling and no padding
patches = mmcv.imcrop(self.img, bboxes, 1.2)
for i in range(len(patches)):
ref_patch = np.load(patch_path + '/scale_{}.npy'.format(i))
self.assert_img_equal(patches[i], ref_patch)
# crop with scaling and padding
patches = mmcv.imcrop(self.img, bboxes, 1.2, pad_fill=[255, 255, 0])
for i in range(len(patches)):
ref_patch = np.load(patch_path + '/pad_{}.npy'.format(i))
self.assert_img_equal(patches[i], ref_patch)
patches = mmcv.imcrop(self.img, bboxes, 1.2, pad_fill=0)
for i in range(len(patches)):
ref_patch = np.load(patch_path + '/pad0_{}.npy'.format(i))
self.assert_img_equal(patches[i], ref_patch)
def test_impad(self):
img = np.random.rand(10, 10, 3).astype(np.float32)
padded_img = mmcv.impad(img, (15, 12), 0)
assert_array_equal(img, padded_img[:10, :10, :])
assert_array_equal(
np.zeros((5, 12, 3), dtype='float32'), padded_img[10:, :, :])
assert_array_equal(
np.zeros((15, 2, 3), dtype='float32'), padded_img[:, 10:, :])
img = np.random.randint(256, size=(10, 10, 3)).astype('uint8')
padded_img = mmcv.impad(img, (15, 12, 3), [100, 110, 120])
assert_array_equal(img, padded_img[:10, :10, :])
assert_array_equal(
np.array([100, 110, 120], dtype='uint8') * np.ones(
(5, 12, 3), dtype='uint8'), padded_img[10:, :, :])
assert_array_equal(
np.array([100, 110, 120], dtype='uint8') * np.ones(
(15, 2, 3), dtype='uint8'), padded_img[:, 10:, :])
with pytest.raises(AssertionError):
mmcv.impad(img, (15, ), 0)
with pytest.raises(AssertionError):
mmcv.impad(img, (5, 5), 0)
with pytest.raises(AssertionError):
mmcv.impad(img, (5, 5), [0, 1])
def test_impad_to_multiple(self):
img = np.random.rand(11, 14, 3).astype(np.float32)
padded_img = mmcv.impad_to_multiple(img, 4)
assert padded_img.shape == (12, 16, 3)
img = np.random.rand(20, 12).astype(np.float32)
padded_img = mmcv.impad_to_multiple(img, 5)
assert padded_img.shape == (20, 15)
img = np.random.rand(20, 12).astype(np.float32)
padded_img = mmcv.impad_to_multiple(img, 2)
assert padded_img.shape == (20, 12)
def test_imrotate(self):
img = np.array([[1, 2, 3], [4, 5, 6], [7, 8, 9]]).astype(np.uint8)
assert_array_equal(mmcv.imrotate(img, 0), img)
img_r = np.array([[7, 4, 1], [8, 5, 2], [9, 6, 3]])
assert_array_equal(mmcv.imrotate(img, 90), img_r)
img_r = np.array([[3, 6, 9], [2, 5, 8], [1, 4, 7]])
assert_array_equal(mmcv.imrotate(img, -90), img_r)
img = np.array([[1, 2, 3, 4], [5, 6, 7, 8]]).astype(np.uint8)
img_r = np.array([[0, 6, 2, 0], [0, 7, 3, 0]])
assert_array_equal(mmcv.imrotate(img, 90), img_r)
img_r = np.array([[1, 0, 0, 0], [2, 0, 0, 0]])
assert_array_equal(mmcv.imrotate(img, 90, center=(0, 0)), img_r)
img_r = np.array([[255, 6, 2, 255], [255, 7, 3, 255]])
assert_array_equal(mmcv.imrotate(img, 90, border_value=255), img_r)
img_r = np.array([[5, 1], [6, 2], [7, 3], [8, 4]])
assert_array_equal(mmcv.imrotate(img, 90, auto_bound=True), img_r)
with pytest.raises(ValueError):
mmcv.imrotate(img, 90, center=(0, 0), auto_bound=True)