ImageApply

ImageApply[f, image] applies the function f to the list of channel values for each pixel in image.

ImageApply[f, {image1, image2, ...}] applies f to corresponding pixel values from each image.

Examples

Invert an image:

img = ExampleData[{"TestImage", "Lena"}];
ImageApply[1 - # &, img]

Apply to multiple images:

ImageApply[Mean, {img, ColorNegate[img]}]

Please visit the official Wolfram Language Reference for more details.