voluptasquisquam/src/image/filter/invertApply.js

Image processing and manipulation in JavaScript

// this code gives the same result as invert()
// but is based on a matrix of pixels
// may be easier to implement some algorithm
// but it will likely be much slower

// this method is 50 times SLOWER than invert !!!!!!

export default function invertApply() {


    if (this.bitDepth === 1) {
        // we simply invert all the integers value
        // there could be a small mistake if the number of points
        // is not a multiple of 8 but it is not important
        let data = this.data;
        for (let i = 0; i < data.length; i++) {
            data[i] = ~data[i];
        }
    } else {
        this.checkProcessable('invertApply', {
            bitDepth: [8, 16]
        });
        this.apply(function (index) {
            for (let k = 0; k < this.components; k++) {
                this.data[index + k] = this.maxValue - this.data[index + k];
            }
        });
    }
}