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 variance in the local neighborhood must be non-zero.

Explanation:

• Mean: The local mean is used to adjust the brightness or average intensity within a specific neighborhood of pixels.
• Variance: The variance measures the spread or contrast of pixel intensities in the local region. Higher variance indicates more contrast or texture, while lower variance suggests a smoother or more uniform region.

Condition:

• Non-zero Variance: Enhancement is effective only when the variance is greater than zero. If the variance is zero, the region is uniform (i.e., all pixels have the same intensity), and no meaningful enhancement can be applied.

In summary, local enhancement using mean and variance is applied when the local variance is non-zero, ensuring that only regions with meaningful variation (contrast or texture) are enhanced.