Another important technique in image processing is thresholding. With the goal of categorizing each pixel in a digital image into different groups (also known as image segmentation), thresholding provides a quick and intuitive way to create binary images (with just black and white pixels).

The idea behind thresholding is to replace each pixel in an image with a white pixel if the pixel's intensity is greater than a previously specified threshold, and with a black pixel if the pixel's intensity is less than that threshold. Similar to the goal of grayscaling, thresholding amplifies the differences between high- and low-intensity pixels, and from that important features and patterns in an image can be recognized and extracted.

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