我发现以下答案使用 PIL 在本地模糊图像: 使用 PIL、python 过滤部分图像。提议的答案裁剪图像的一部分,对其进行模糊处理并将其复制回原始图像。这会在模糊部分和原始图像之间创建锐利边缘(请参见下面的示例)。
我想避免这种影响。
要避免此问题,可以使用以下过程:
下面是一些使用 scipy 的示例代码:
import numpy as np
import matplotlib.pyplot as plt
from scipy import misc
import scipy.ndimage
def gaussian_blur(sharp_image, sigma):
# Filter channels individually to avoid gray scale images
blurred_image_r = scipy.ndimage.filters.gaussian_filter(sharp_image[:, :, 0], sigma=sigma)
blurred_image_g = scipy.ndimage.filters.gaussian_filter(sharp_image[:, :, 1], sigma=sigma)
blurred_image_b = scipy.ndimage.filters.gaussian_filter(sharp_image[:, :, 2], sigma=sigma)
blurred_image = np.dstack((blurred_image_r, blurred_image_g, blurred_image_b))
return blurred_image
def uniform_blur(sharp_image, uniform_filter_size):
# The multidimensional filter is required to avoid gray scale images
multidim_filter_size = (uniform_filter_size, uniform_filter_size, 1)
blurred_image = scipy.ndimage.filters.uniform_filter(sharp_image, size=multidim_filter_size)
return blurred_image
def blur_image_locally(sharp_image, mask, use_gaussian_blur, gaussian_sigma, uniform_filter_size):
one_values_f32 = np.full(sharp_image.shape, fill_value=1.0, dtype=np.float32)
sharp_image_f32 = sharp_image.astype(dtype=np.float32)
sharp_mask_f32 = mask.astype(dtype=np.float32)
if use_gaussian_blur:
blurred_image_f32 = gaussian_blur(sharp_image_f32, sigma=gaussian_sigma)
blurred_mask_f32 = gaussian_blur(sharp_mask_f32, sigma=gaussian_sigma)
else:
blurred_image_f32 = uniform_blur(sharp_image_f32, uniform_filter_size)
blurred_mask_f32 = uniform_blur(sharp_mask_f32, uniform_filter_size)
blurred_mask_inverted_f32 = one_values_f32 - blurred_mask_f32
weighted_sharp_image = np.multiply(sharp_image_f32, blurred_mask_f32)
weighted_blurred_image = np.multiply(blurred_image_f32, blurred_mask_inverted_f32)
locally_blurred_image_f32 = weighted_sharp_image + weighted_blurred_image
locally_blurred_image = locally_blurred_image_f32.astype(dtype=np.uint8)
return locally_blurred_image
if __name__ == '__main__':
sharp_image = misc.face()
height, width, channels = sharp_image.shape
sharp_mask = np.full((height, width, channels), fill_value=1)
sharp_mask[int(height / 4): int(3 * height / 4), int(width / 4): int(3 * width / 4), :] = 0
result = blur_image_locally(
sharp_image,
sharp_mask,
use_gaussian_blur=True,
gaussian_sigma=31,
uniform_filter_size=201)
plt.imshow(result)
plt.show()
我也在寻找解决这个问题的优雅方法。 ChatGPT 只提供了部分帮助,我需要想出一种自己的方法,主要受 https://note.nkmk.me/en/python-pillow-composite/.
的影响总而言之:
from PIL import Image, ImageFilter, ImageDraw
def apply_blur_with_gradient(image_path, output_path, blur_area, blur_radius, gradient_width):
# Load the original image
image = Image.open(image_path)
# Create the blurred area
blurred_image = image.filter(ImageFilter.GaussianBlur(blur_radius))
# Create the gradient mask
mask = Image.new("L", image.size, 255)
draw = ImageDraw.Draw(mask)
draw.rectangle(blur_area, fill=0)
mask = mask.filter(ImageFilter.GaussianBlur(gradient_width))
# Composite the images using Image.composite
output = Image.composite(image, blurred_image, mask)
# Alternatively, you can use the paste method
# output = blurred_image.copy()
# output.paste(image, mask)
# Save the output image
output.save(output_path)
# Usage
image_path = 'path/to/your/image.jpg'
output_path = 'output_image.jpg'
blur_area = (100, 150, 300, 400) # x1, y1, x2, y2
blur_radius = 10 # Gaussian blur radius
gradient_width = 20 # Gradient width for smooth transition
apply_blur_with_gradient(image_path, output_path, blur_area, blur_radius, gradient_width)
print("Task completed! Check 'output_image.jpg'.")
这最终也应该满足“优雅”的要求,至少我试图让它尽可能简单,并且用尽可能少的代码行。