White Balance¶
Corrects the exposure of an image. A color standard can be specified.
plantcv.white_balance(img, mode='hist', roi=None)
returns corrected_img
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Parameters:
- img - RGB (or grayscale, though not recommended) image data on which to perform the correction
- mode - either 'hist' or 'max'. If 'hist' (default) method is used a histogram for the whole image or the specified ROI is calculated, and the bin with the most pixels is used as a reference point to shift image values. If 'max' is used as a method, then the pixel with the maximum value in the whole image or the specified ROI is used as a reference point to shift image values.
- roi - A list of 4 points (x, y, width, height) that form the rectangular ROI of the white color standard. If a list of 4 points is not given, the whole image is used (default: None)
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Context:
- Used to standardize exposure of images before thresholding
Original image
from plantcv import plantcv as pcv
# Set global debug behavior to None (default), "print" (to file), or "plot" (Jupyter Notebooks or X11)
pcv.params.debug = "print"
# Corrects image based on color standard and stores output as corrected_img
corrected_img = pcv.white_balance(img, mode='hist', roi=(5, 5, 80, 80))
Corrected image
Source Code: Here