For a local enhancement using mean and variance, there is one condition: σs(x, y) ≤ k2DG, where, MDG is global standard deviation, k2 a positive constant and σs(x, y) a measure of contrast at point (x, y). Then, which fact is true for k2 if its values is greater than 1.0?

Question

For a local enhancement using mean and variance, there is one condition:

Answer 1

For local enhancement using mean and variance, the condition is:

The local variance must be higher than a certain threshold to apply enhancement effectively.

Explanation:

• Mean: The local mean calculates the average pixel intensity in a given neighborhood.
• Variance: The local variance measures how much the pixel intensities deviate from the mean. High variance indicates regions with detailed features (like edges or textures), while low variance indicates smooth, uniform regions.

Key Condition:

• High Variance: Effective enhancement is typically applied when the variance in the local region is high. This means that the region contains more detailed features that can be enhanced (e.g., edges or textures).
• Low Variance: Regions with low variance are smooth and featureless, so enhancement is usually not needed or is applied minimally.

This condition ensures that local enhancement focuses on regions with noticeable texture or contrast, avoiding unnecessary enhancement of uniform areas.