Question

A 4 × 4 digital image has pixel intensities (U) as shown in the figure. The number of pixels with \( U \leq 4 \) is:

 

• A. 3
• B. 8
• C. 11
• D. 9

Hint:

In digital images, when analyzing pixel intensities, always look for the specific threshold conditions (like \( U \leq 4 \)) and count the pixels that satisfy the condition across the entire matrix.

Answer 1

The Correct Option is C

We are asked to find how many pixels have intensities less than or equal to 4. 
Let’s go through the matrix and count the number of pixels that satisfy \( U \leq 4 \).
The given matrix of pixel intensities is:

• Row 1: 0, 1, 0, 2 (all are \( \leq 4 \)) - Count: 4
• Row 2: 4, 7, 3, 3 (4, 3, 3 are \( \leq 4 \)) - Count: 3
• Row 3: 5, 5, 4, 4 (4, 4 are \( \leq 4 \)) - Count: 2
• Row 4: 6, 7, 3, 2 (3, 2 are \( \leq 4 \)) - Count: 2

Total count: \( 4 + 3 + 2 + 2 = 11 \)