machinevisiontoolbox.Image.normhist

Image.normhist()

Histogram normalisaton

Returns:

normalised image

Return type:

Image instance

Return a histogram normalized version of the image which highlights image detail in low-contrast areas of an image.

Example:

>>> from machinevisiontoolbox import Image
>>> img = Image([[10, 20, 30], [40, 41, 42], [70, 80, 90]])
>>> img.normhist().A
array([[  0,  32,  64],
       [ 96, 128, 159],
       [191, 223, 255]], dtype=uint8)
Note:

  • The histogram of the normalized image is approximately uniform, that is, all grey levels ae equally likely to occur.

  • Color images automatically converted to grayscale

References:

  • Robotics, Vision & Control for Python, Section 11.3, P. Corke, Springer 2023.

Seealso:

cv2.equalizeHist