refactored resize (#1562)

Co-authored-by: h <f>
Co-authored-by: Harsh Khandeparkar <34770591+HarshKhandeparkar@users.noreply.github.com>
Co-authored-by: Jeffrey Warren <jeff@unterbahn.com>

src/modules/Resize/Module.js

@@ -1,6 +1,3 @@
-const imagejs = require('imagejs'),
-  pixelSetter = require('../../util/pixelSetter'),
-  ndarray = require('ndarray');
 /*
  * Resize the image by given percentage value
  */
@@ -19,44 +16,7 @@ module.exports = function Resize(options, UI) {
     const step = this;
 
     function extraManipulation(pixels) {
-      // Value above 100% scales up, and below 100% scales down
-      const resize_value = parseInt(options.resize.slice(0, -1));
-
-      if (resize_value == 100) return pixels;
-
-
-      const new_width = Math.round(pixels.shape[0] * (resize_value / 100)),
-        new_height = Math.round(pixels.shape[1] * (resize_value / 100));
-
-      const bitmap = new imagejs.Bitmap({ width: pixels.shape[0], height: pixels.shape[1] });
-
-      for (let x = 0; x < pixels.shape[0]; x++) {
-        for (let y = 0; y < pixels.shape[1]; y++) {
-          let r = pixels.get(x, y, 0),
-            g = pixels.get(x, y, 1),
-            b = pixels.get(x, y, 2),
-            a = pixels.get(x, y, 3);
-
-          bitmap.setPixel(x, y, r, g, b, a);
-        }
-      }
-
-      const resized = bitmap.resize({
-        width: new_width,
-        height: new_height,
-        algorithm: 'bicubicInterpolation'
-      });
-
-      const newPix = new ndarray([], [new_width, new_height, 4]);
-
-      for (let x = 0; x < new_width; x++) {
-        for (let y = 0; y < new_height; y++) {
-          const {r, g, b, a} = resized.getPixel(x, y);
-          pixelSetter(x, y, [r, g, b, a], newPix);
-        }
-      }
-
-      return newPix;
+      return require('./Resize')(pixels, options);
     }
 
     function output(image, datauri, mimetype, wasmSuccess) {

src/modules/Resize/Resize.js

@@ -0,0 +1,44 @@
+const imagejs = require('imagejs'),
+  pixelSetter = require('../../util/pixelSetter'),
+  ndarray = require('ndarray');
+module.exports = function Resize(pixels, options) {
+  const resize_value = parseInt(options.resize.slice(0, -1));
+
+  if (resize_value == 100) return pixels;
+
+  const new_width = Math.round(pixels.shape[0] * (resize_value / 100)),
+    new_height = Math.round(pixels.shape[1] * (resize_value / 100));
+
+  const bitmap = new imagejs.Bitmap({
+    width: pixels.shape[0],
+    height: pixels.shape[1]
+  });
+
+  for (let x = 0; x < pixels.shape[0]; x++) {
+    for (let y = 0; y < pixels.shape[1]; y++) {
+      let r = pixels.get(x, y, 0),
+        g = pixels.get(x, y, 1),
+        b = pixels.get(x, y, 2),
+        a = pixels.get(x, y, 3);
+
+      bitmap.setPixel(x, y, r, g, b, a);
+    }
+  }
+
+  const resized = bitmap.resize({
+    width: new_width,
+    height: new_height,
+    algorithm: 'bicubicInterpolation'
+  });
+
+  const newPix = new ndarray([], [new_width, new_height, 4]);
+
+  for (let x = 0; x < new_width; x++) {
+    for (let y = 0; y < new_height; y++) {
+      const { r, g, b, a } = resized.getPixel(x, y);
+      pixelSetter(x, y, [r, g, b, a], newPix);
+    }
+  }
+
+  return newPix;
+};