image-js/lib/image/utility/getColumn.js

Image processing and manipulation in JavaScript

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = getColumn;
var _checks = require("../internal/checks");
/**
 * @memberof Image
 * @instance
 * @param {number} column
 * @param {number} [channel=0]
 * @return {number[]}
 */
function getColumn(column, channel = 0) {
  this.checkProcessable('getColumn', {
    bitDepth: [8, 16]
  });
  (0, _checks.checkColumn)(this, column);
  (0, _checks.checkChannel)(this, 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;
}