Gradients and Detail

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1. Which explanation matches horizontal and vertical image gradients?A. Nonmaximum suppression keeps a local peak along the gradient direction.B. Canny detection smooths, measures gradients, thins responses, and uses two linked thresholds.C. Horizontal and vertical derivatives measure intensity change across each axis.D. Sharpening boosts high-frequency contrast, often by adding a scaled detail component.

2. Which explanation matches from gradient map to thin edges?A. Horizontal and vertical derivatives measure intensity change across each axis.B. Nonmaximum suppression keeps a local peak along the gradient direction.C. Canny detection smooths, measures gradients, thins responses, and uses two linked thresholds.D. Sharpening boosts high-frequency contrast, often by adding a scaled detail component.

3. Which explanation matches canny thresholds in different scenes?A. Canny detection smooths, measures gradients, thins responses, and uses two linked thresholds.B. Horizontal and vertical derivatives measure intensity change across each axis.C. Nonmaximum suppression keeps a local peak along the gradient direction.D. Sharpening boosts high-frequency contrast, often by adding a scaled detail component.

4. For from gradient map to thin edges, which result or action fits this practical case: A thick gradient band covers several pixels beside a sharp boundary.A. Combine horizontal and vertical responses to estimate edge strength and direction.B. Retain a weak edge connected to a strong edge while rejecting an isolated weak speck.C. Compare moderate unsharp masking with an excessive setting near a high-contrast line.D. Thin a wide response before treating it as a final edge map.

5. For sharpen without creating halos, which result or action fits this practical case: A sharpened scan develops pale outlines around dark details.A. Combine horizontal and vertical responses to estimate edge strength and direction.B. Thin a wide response before treating it as a final edge map.C. Compare moderate unsharp masking with an excessive setting near a high-contrast line.D. Retain a weak edge connected to a strong edge while rejecting an isolated weak speck.

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Gradients and Detail

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