Description:

This PR introduces two new image processing functions to the PIL.ImageOps module:

sepia

Applies a classic sepia tone effect to RGB images.

Converts the image to RGB if necessary.

Computes new pixel values using the standard sepia formula and clamps results to [0, 255].

Preserves the original image size and mode.

Practical use: adds a warm, vintage look to images with minimal processing overhead.

neon_effect

Applies a neon/glow effect to an image.

Internally uses a Sobel edge-detection filter , Gaussian blur, and colorization.

Combines the neon layer with the original image using alpha blending.

Supports RGB images and customizable neon color.

Practical use: highlights edges and details in a visually striking, glowing style.

Benefits:

Expands Pillow’s “ready-made” filters with two highly requested effects.

Provides developers with visually appealing filters without third-party dependencies.

Results

Image after sepia effect:

Image after neon-glow effect:

Notes

There are tests for all functions created in this PR covering the main basic behaviors