Structure and Segmentation

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1. Which explanation matches edges and sharpening are not the same?A. Gradient filters estimate how strongly intensity changes in horizontal and vertical directions.B. A global threshold applies the same cutoff everywhere.C. For a binary foreground mask, erosion tends to shrink foreground regions, while dilation tends to expand them.D. With four-connectivity, pixels connect through their left, right, upper, and lower neighbors.

2. Which explanation matches thresholding: turn intensities into a mask?A. Gradient filters estimate how strongly intensity changes in horizontal and vertical directions.B. For a binary foreground mask, erosion tends to shrink foreground regions, while dilation tends to expand them.C. With four-connectivity, pixels connect through their left, right, upper, and lower neighbors.D. A global threshold applies the same cutoff everywhere.

3. Which explanation matches morphology: clean a binary mask carefully?A. Gradient filters estimate how strongly intensity changes in horizontal and vertical directions.B. A global threshold applies the same cutoff everywhere.C. For a binary foreground mask, erosion tends to shrink foreground regions, while dilation tends to expand them.D. With four-connectivity, pixels connect through their left, right, upper, and lower neighbors.

4. For a document with a bright center and dark corners, explain one reason to compare global and adaptive thresholding.A. No. Both can produce strong gradients. Distinguishing their meanings requires additional context or a more complete model.B. A single global cutoff may lose faint central text or include dark corner backgrounds. Local thresholds may handle the illumination variation more consistently.C. Opening may remove small specks. It could also remove a thin cable, a small grain, or another narrow foreground structure.D. Four-connectivity produces two components; eight-connectivity produces one.

5. Two pixels touch only at a corner. How many components do four-connectivity and eight-connectivity produce?A. Four-connectivity produces two components; eight-connectivity produces one.B. No. Both can produce strong gradients. Distinguishing their meanings requires additional context or a more complete model.C. A single global cutoff may lose faint central text or include dark corner backgrounds. Local thresholds may handle the illumination variation more consistently.D. Opening may remove small specks. It could also remove a thin cable, a small grain, or another narrow foreground structure.

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Structure and Segmentation

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