EP03_01 — ➕ Saturated Addition of a Constant

3.14.1 EP03_01 ➕ Saturated Addition of a Constant

In video surveillance systems, cameras in environments with variable lighting produce underexposed images. Adjusting brightness by saturated addition of a constant is the simplest operation for immediate correction, being applied in real time on embedded camera chips and in preprocessing pipelines of mobile robots.

See Figure 3.26 for a simulation of this EP.

3.14.1.1 📋 Implementation Guidelines

Dimensions: Read the integers \(L\) (rows) and \(C\) (columns).
Constant: Read the integer \(k\) (value to be added).
Data: Read the integer values of the original matrix row by row.
Mapping: For each pixel \(p\), compute the new value using the equation:

\[p' = \text{clip}(p + k)\]

Output: Display the resulting matrix with dimensions \(L \times C\).

3.14.1.2 📌 Computational Constraints

Saturation (Clipping): Values must be confined to the interval \([0, 255]\): \[\text{clip}(x) = \max(0, \min(255, x))\]
Type: The final result must be an integer (no decimal places).
\(k\) can be negative: negative values darken the image; positive values lighten it.

3.14.1.3 🧠 Theoretical Background

Parameter	Type	Visual Impact
\(k > 0\)	Integer	Lightens the image; pixels near 255 saturate to white
\(k < 0\)	Integer	Darkens the image; pixels near 0 saturate to black
\(k = 0\)	Integer	Image unchanged

3.14.1.4 📦 Input and Output Specification (VPL)

Input:

Line 1: Integer \(L\).
Line 2: Integer \(C\).
Line 3: Integer \(k\).
Following lines: Integer elements of the original matrix.

Output:

Transformed matrix with \(L\) rows and \(C\) columns, integer values separated by spaces.

3.14.1.5 📌 Examples

Input	Output	Observation
2 3 50 0 100 200 210 240 255	50 150 250 255 255 255	Saturation at 255 for high pixels
1 4 -30 0 20 200 255	0 0 170 225	Saturation at 0 for low pixels

➕ Simulator EP03_01: Constant Saturated Addition p' = clip(p + k)

Adjust the constant value k to observe the image brightness shift and saturation truncation in the range [0, 255].

Constant (k) 0

Original Input (p)

Transformed Result (p')

      Formula applied: clip(p + (0))

Figure 3.26: Simulador EP03_01: Saturated Addition of Constant (p’ = clip(p + k))

%%writefile EP03_01.py
# Python code

Overwriting EP03_01.py

TestSuite("EP03_01.py").run()

✔️ EP03_01.cases already exists in casos/
📋 5 case(s) loaded from casos/EP03_01.cases

🔍 Testing Python: EP03_01.py
⚠️ EP03_01.py: Empty file (fewer than 3 lines). Tests skipped.