Which factor affects displayed image contrast during post-processing by altering the range of gray values?

Which factor affects displayed image contrast during post-processing by altering the range of gray values?

• A. Histogram analysis
• B. Window width (WW)
• C. Grayscale standard display function (GSDF)
• D. Automatic brightness control (ABC)

Answer: (B)

Window width controls the range of gray values that are mapped to the display. By narrowing that range, fewer gray shades are used and subtle differences between tissues become more distinct, increasing image contrast. Widening the range spreads many gray values across the display, which smooths differences and lowers contrast. The window level simply centers this range and affects brightness, not the width of the range. Histogram analysis helps choose window/level values by examining the image’s data distribution, GSDF defines a standardized perceptual display response rather than a user-controlled range, and automatic brightness control adjusts overall brightness without changing the width of the mapped gray-scale range.

Window width controls the range of gray values that are mapped to the display. By narrowing that range, fewer gray shades are used and subtle differences between tissues become more distinct, increasing image contrast. Widening the range spreads many gray values across the display, which smooths differences and lowers contrast. The window level simply centers this range and affects brightness, not the width of the range.

Histogram analysis helps choose window/level values by examining the image’s data distribution, GSDF defines a standardized perceptual display response rather than a user-controlled range, and automatic brightness control adjusts overall brightness without changing the width of the mapped gray-scale range.