voluptasquisquam/src/image/utility/getColumn.js

Image processing and manipulation in JavaScript

/**
 * @memberof Image
 * @instance
 * @param {number} column
 * @param {number} [channel=0]
 * @return {number[]}
 */
export default function getColumn(column, channel = 0) {

    this.checkProcessable('getColumn', {
        bitDepth: [8, 16]
    });

    this.checkColumn(column);
    this.checkChannel(channel);

    let array = new Array(this.height);
    let ptr = 0;
    let step = this.width * this.channels;
    for (let j = channel + column * this.channels; j < this.data.length; j += step) {
        array[ptr++] = this.data[j];
    }
    return array;
}