Adaptive Threshold¶

Creates a binary image from a gray image using adaptive thresholding.

adaptive_threshold(img, maxValue, thres_type, object_type, device, debug=None)

returns device, thresholded image

• Parameters:
  • img - grayscale img object
  • maxValue - value to apply above threshold (255 = white)
  • thres_type = type of thresholding ('gaussian' or 'mean')
  • objecttype - 'light' or 'dark', is target image light or dark?
  • device- Counter for image processing steps
  • debug- None, "print", or "plot". Print = save to file, Plot = print to screen. Default = None
• Context:
  • Used to help differentiate plant and background

Grayscale image (green-magenta channel)

import plantcv as pcv

# Create binary image from a gray image based
device, threshold_gaussian = pcv.adaptive_threshold(img, 255, 'gaussian','dark', device, debug="print")

Auto-Thresholded image (gaussian)

import plantcv as pcv

# Create binary image from a gray image based 
device, threshold_mean = pcv.adaptive_threshold(img, 255, 'mean','dark', device, debug="print")

Auto-Thresholded image (mean)