Hi and welcome
This may help
https://funprogramming.org/90-Change-pixel-hue-saturation-and-brightness.html
https://funprogramming.org/89-Create-your-own-photo-filters.html
https://funprogramming.org/88-Change-pixels-using-the-pixels-array.html
https://funprogramming.org/81-How-to-read-the-color-of-a-pixel.html