A 4 × 4 digital image has pixel intensities (𝑈) as shown in the figure. The number of pixels with 𝑈 ≤ 4 is:
A.
3
B.
8
C.
11
D.
9
Solution:
We are given a 4 × 4 digital image with pixel intensities, and asked to count how many pixels have intensity U ≤ 4.
Let’s read the matrix from the image:
0 1 0 2
4 7 3 3
5 5 4 4
6 7 3 2
Now, count the number of values ≤ 4:
Row 1: 0, 1, 0, 2 → ✅ all 4
Row 2: 4, 7, 3, 3 → ✅ 4, 3, 3 → 3
Row 3: 5, 5, 4, 4 → ✅ 4, 4 → 2
Row 4: 6, 7, 3, 2 → ✅ 3, 2 → 2