# Copyright (C) 2023 Deforum LLC | |
# | |
# This program is free software: you can redistribute it and/or modify | |
# it under the terms of the GNU Affero General Public License as published by | |
# the Free Software Foundation, version 3 of the License. | |
# | |
# This program is distributed in the hope that it will be useful, | |
# but WITHOUT ANY WARRANTY; without even the implied warranty of | |
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
# GNU General Public License for more details. | |
# | |
# You should have received a copy of the GNU Affero General Public License | |
# along with this program. If not, see <https://www.gnu.org/licenses/>. | |
# Contact the authors: https://deforum.github.io/ | |
import cv2 | |
import numpy as np | |
def unsharp_mask(img, kernel_size=(5, 5), sigma=1.0, amount=1.0, threshold=0, mask=None): | |
if amount == 0: | |
return img | |
# Return a sharpened version of the image, using an unsharp mask. | |
# If mask is not None, only areas under mask are handled | |
blurred = cv2.GaussianBlur(img, kernel_size, sigma) | |
sharpened = float(amount + 1) * img - float(amount) * blurred | |
sharpened = np.maximum(sharpened, np.zeros(sharpened.shape)) | |
sharpened = np.minimum(sharpened, 255 * np.ones(sharpened.shape)) | |
sharpened = sharpened.round().astype(np.uint8) | |
if threshold > 0: | |
low_contrast_mask = np.absolute(img - blurred) < threshold | |
np.copyto(sharpened, img, where=low_contrast_mask) | |
if mask is not None: | |
mask = np.array(mask) | |
masked_sharpened = cv2.bitwise_and(sharpened, sharpened, mask=mask) | |
masked_img = cv2.bitwise_and(img, img, mask=255-mask) | |
sharpened = cv2.add(masked_img, masked_sharpened) | |
return sharpened |