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 less 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 sufficiently large to detect significant features and apply enhancement.

Explanation:

• Mean helps adjust the brightness of a region, while variance captures the amount of contrast or texture within a local window.
• High variance indicates areas with significant detail (e.g., edges or textures), which are ideal for enhancement.
• Low variance corresponds to smooth, uniform areas, where enhancement may not be necessary or could result in noise amplification.

Therefore, the condition for local enhancement is that the variance must exceed a certain threshold to ensure the enhancement is applied only to regions that contain meaningful detail, improving the image contrast where it's needed most.