"""
Wraps all the functionality required for applying blurring techniques to an image.
"""
import cv2
__authors__ = "Stephan Nell, Nicolai van Niekerk"
__copyright__ = "Copyright 2017, Java the Hutts"
__license__ = "BSD"
__maintainer__ = "Stephan Nell"
__email__ = "nellstephanj@gmail.com"
__status__ = "Development"
[docs]class BlurManager:
"""
The blur is responsible for applying different blur techniques to the images passed.
"""
def __init__(self, blur_type, kernel_size):
"""
Initialise Blur Manager.
:param blur_type (str): Indicates the type of blur operation that should be applied to the image.
:param kernel_size (int tuple): Indicates the kernel size for blurring operations.
Raises:
- TypeError: If a none string value is passed for blur_type.
"""
if not isinstance(blur_type, str):
raise TypeError(
'Bad type for arg blur_type - expected string. Received type "%s".' %
type(blur_type).__name__
)
self.blur_type = blur_type
self.kernel_size = kernel_size
[docs] def apply(self, image):
"""
This performs the blurring.
:param image: The image to be blurred.
Raises:
- NameError: If invalid blur type is provided i.e. Normal, Gaussian or Median.
Returns:
- (obj): The blurred OpenCV image.
"""
if self.blur_type == "gaussian":
return self.gaussianBlur(image, self.kernel_size)
elif self.blur_type == "normal":
return self.blur(image, self.kernel_size)
elif self.blur_type == "median":
return self.medianBlur(image, self.kernel_size)
else:
raise NameError('Invalid Blur Selection! Try "normal", "gaussian" or "median" thresholding types.')
[docs] def blur(self, image, blur_kernel=[(3, 3)]):
"""
This function applies basic blurring to the image passed.
:param image (obj): OpenCV image to which basic blurring should be applied to.
:param blur_kernel (int list): Represent the kernel dimension by which basic blurring should be applied to.
Raises:
- ValueError: If a blur_kernel with an invalid length is provided.
- TypeError: If a blur_kernel is not of type list.
Returns:
- (obj): A modified copy of the OpenCV image where basic blurring was applied to the image.
"""
if not (isinstance(blur_kernel, list)):
raise TypeError('Invalid kernel type provided for normal blurring. Blur kernel supports list type')
if not len(blur_kernel[0]) == 2:
raise ValueError('Invalid kernel size - blur_kernel list can only contain 2 items.')
for (kX, kY) in blur_kernel:
blurred = cv2.blur(image, (kX, kY))
return blurred
[docs] def gaussianBlur(self, image, blur_kernel=[(7, 7)]):
"""
This function applies Gaussian blurring to the image passed.
:param image (obj): OpenCV image to which Gaussian blurring should be applied to.
:param blur_kernel (Integer list): Represent the kernel dimension by which basic blurring
should be applied to.
Raises:
- ValueError: If a blur_kernel with an invalid length is provided.
- TypeError: If a blur_kernel is not of type list.
Returns:
- (obj): A modified copy of the OpenCV image where Gaussian blurring was applied to the image.
"""
if not (isinstance(blur_kernel, list)):
raise TypeError('Invalid kernel type provided for gaussian blur. Blur kernel supports list type.')
if not len(blur_kernel[0]) == 2:
raise ValueError('Invalid kernel size - blur_kernel list can only contain 2 items.')
for (kX, kY) in blur_kernel:
blurred = cv2.GaussianBlur(image, (kX, kY), 0)
return blurred