pycharmers.opencv.binary module

pycharmers.opencv.binary.binarizer_creator(method, maxval=255, thresh=127, thresholdType=0, blockSize=11, const=2)[source]

Returns a function which performs advanced morphological transformations.

Parameters
  • method (str/int) – The identifier of binarization.

  • thresh (int) – Threshold value used in "fixed" binarizer.

  • maxval (int) – The maximum value.

  • thresholdType (int) – Thresholding type.

  • blockSize (odd) – Size of a pixel neighborhood that is used to calculate a threshold value for the pixel: 3 , 5 , 7 , and so on.

  • const (int) – Constant subtracted from the mean or weighted mean (see the details below). Normally, it is positive but may be zero or negative as well.

Returns

Binarizer.

Return type

function

Examples

>>> import cv2
>>> from pycharmers.opencv import binarizer_creator, SAMPLE_LENA_IMG, vconcat_resize_min, cv2plot
>>> from pycharmers.opencv.binary import OPENCV_BINARYZATIONS
>>> gray = cv2.imread(SAMPLE_LENA_IMG, 0)
>>> images = [gray]
>>> images.extend([binarizer_creator(key)(gray) for key in OPENCV_BINARYZATIONS.keys()])
>>> ax = cv2plot(vconcat_resize_min(*images), cmap="binary", figkeywargs={"figsize": (10,10)})
pycharmers.opencv.binary.findBiggestContour(contours, eta=0.1)[source]
Parameters

contours (list) – Contours. (e.g. The return of cv2.findContours )

Returns

Countour of the biggest area. max_area (int) : Area of the biggest area.

Return type

biggest (np.ndarray)

Examples

>>> import cv2
>>> from pycharmers.opencv import findBiggestContour, SAMPLE_LENA_IMG
>>> img_gray = cv2.imread(SAMPLE_LENA_IMG, 0)
>>> img_th = cv2.Canny(img_gray, 100, 100)
>>> contours, hierarchy = cv2.findContours(image=img_th, mode=cv2.RETR_EXTERNAL, method=cv2.CHAIN_APPROX_SIMPLE)
>>> biggest, max_area = findBiggestContour(contours, eta=0.2)
>>> max_area
0 # There is no closed countour.
pycharmers.opencv.binary.reorder_contour(points)[source]

Reorder the points created by cv2.approxPolyDP

Parameters

points (np.ndarray) – Points.

Returns

Reordered Points.

Return type

ret (np.ndarray)