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              "value": "The Scharr operator has a better rotation invariance than other edge filters such as the Sobel or the Prewitt operators."
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                      "value": "The Scharr edge map."
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              "value": "Find the edge magnitude using the Scharr transform."
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    ".. [1] D. Kroon, 2009, Short Paper University Twente, Numerical",
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