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Gamma Correction

Implement a point operator to apply gamma correction to an image. This process transforms the image's intensity values to adjust its brightness and contrast.

Gamma correction is a non-linear operation that modifies the image's pixel values based on a power-law relationship, which can brighten or darken regions. The gamma value determines the amount of correction, where values less than 1 increase the brightness of dark areas and values greater than 1 decrease the brightness.

Here are the steps to perform gamma correction:

Normalize the input image intensity values to the range [0,1].
Raise each normalized value to the power of gamma.
Scale the result back to the original range [0,255].

I_{out} = 255 \cdot \left(\frac{I_{in}}{255}\right)^\gamma

This technique is widely used in image and video processing applications to adjust the display's brightness and contrast.

Example:

Input:

gamma_correct([[64, 128]], 0.5)

Output:

[[128, 181]]

Reasoning:

First, apply the formula $I_{out} = 255 \cdot \left(\frac{I_{in}}{255}\right)^{0.5}$ to each pixel value in $[[64, 128]]$ .
For $64$ : $\frac{64}{255} \approx 0.251$ , then $0.251^{0.5} \approx 0.501$ , and $255 \cdot 0.501 \approx 128$ .
For $128$ : $\frac{128}{255} \approx 0.502$ , then $0.502^{0.5} \approx 0.708$ , and $255 \cdot 0.708 \approx 181$ .
Rounding these results gives the output $[[128, 181]]$ .

Constraints:

gamma > 0
Output rounded to nearest integer

Editor

Python 3.13.1

Test Results

0/0

Run code to see test results.

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