Merge pull request #112 from raccoonback/specify-max-canvas-size

[bug] specify the maximum size of Canvas supported by each browser

README.md

@@ -52,6 +52,8 @@ or
 const options = { 
   maxSizeMB: number,          // (default: Number.POSITIVE_INFINITY)
   maxWidthOrHeight: number,   // compressedFile will scale down by ratio to a point that width or height is smaller than maxWidthOrHeight (default: undefined)
+                              // but, automatically reduce the size to smaller than the maximum Canvas size supported by each browser.
+                              // Please check the Cabeat part for details.
   onProgress: Function,       // optional, a function takes one progress argument (percentage from 0 to 100) 
   useWebWorker: boolean,      // optional, use multi-thread web worker, fallback to run in main-thread (default: true)
 
@@ -64,6 +66,20 @@ const options = {
 
 imageCompression(file: File, options): Promise<File>
 ```
+
+#### Caveat ####
+Each browser limits [the maximum size](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/canvas#maximum_canvas_size) of a Canvas object. <br/>
+So, we resize the image to less than the maximum size that each browser restricts. <br/>
+(However, the `proportion/ratio` of the image remains.)
+
+| Browser | Maximum height | Maximum width | Maximum area |
+|---|---|---|---|
+| Chrome | 32,767 pixels | 32,767 pixels | 268,435,456 pixels (i.e., 16,384 x 16,384) |
+| Firefox | 32,767 pixels | 32,767 pixels | 472,907,776 pixels (i.e., 22,528 x 20,992) |
+| Safari | 32,767 pixels | 32,767 pixels | 268,435,456 pixels (i.e., 16,384 x 16,384) |
+| IE | 8,192 pixels | 8,192 pixels | ? |
+| Etc | ? | ? | ? |
+
 ### Helper function ###
 - for advanced users only, most users won't need to use the helper functions
 ```javascript

lib/config/max-canvas-size.js

@@ -0,0 +1,8 @@
+// https://developer.mozilla.org/en-US/docs/Web/HTML/Element/canvas#maximum_canvas_size
+export default {
+    "chrome": 16384,
+    "firefox": 22528,
+    "safari": 16384,
+    "internet explorer": 8192,
+    "etc": 8192
+}

lib/utils.js

@@ -1,4 +1,6 @@
 import UPNG from './UPNG'
+import Bowser  from "bowser";
+import MaxCanvasSize from './config/max-canvas-size'
 
 const isBrowser = typeof window !== 'undefined' // change browser environment to support SSR
 
@@ -102,14 +104,54 @@ export function loadImage (src) {
   })
 }
 
+/**
+ * approximateBelowCanvasMaximumSizeOfBrowser
+ *
+ * it uses binary search to converge below the browser's maximum Canvas size.
+ *
+ * ref: https://developer.mozilla.org/en-US/docs/Web/HTML/Element/canvas#maximum_canvas_size
+ *
+ * @param {number} initWidth
+ * @param {number} initHeight
+ * @returns {object}
+ */
+function approximateBelowMaximumCanvasSizeOfBrowser(initWidth, initHeight) {
+  const browserName = getBrowserName()
+  const maximumCanvasSize = MaxCanvasSize[browserName]
+
+  let width = initWidth;
+  let height = initHeight
+  let size = width * height
+  const ratio = width > height ? height / width : width / height
+
+  while(size > maximumCanvasSize * maximumCanvasSize) {
+    const halfSizeWidth = (maximumCanvasSize + width) / 2;
+    const halfSizeHeight = (maximumCanvasSize + height) / 2;
+    if(halfSizeWidth < halfSizeHeight) {
+      height = halfSizeHeight
+      width = halfSizeHeight * ratio
+    } else {
+      height = halfSizeWidth * ratio
+      width = halfSizeWidth
+    }
+
+    size = width * height
+  }
+
+  return {
+    width, height
+  }
+}
+
 /**
  * drawImageInCanvas
  *
  * @param {HTMLImageElement} img
  * @returns {HTMLCanvasElement | OffscreenCanvas}
  */
 export function drawImageInCanvas (img) {
-  const [canvas, ctx] = getNewCanvasAndCtx(img.width, img.height)
+  const {width, height} = approximateBelowMaximumCanvasSizeOfBrowser(img.width, img.height)
+  const [canvas, ctx] = getNewCanvasAndCtx(width, height)
   ctx.drawImage(img, 0, 0, canvas.width, canvas.height)
   return canvas
 }
@@ -350,3 +392,20 @@ if (isBrowser) {
       Math.floor(value) === value
   }
 }
+
+/**
+ * getBrowserName
+ *
+ * Extracts the browser name from the useragent.
+ *
+ * @returns {string}
+ */
+export function getBrowserName() {
+  const browserName = Bowser.parse(globalThis.navigator.userAgent).browser.name || ''
+  const lowerCasedBrowserName = browserName.toLowerCase()
+  if(['chrome', 'safari', 'firefox'].includes(lowerCasedBrowserName)) {
+    return lowerCasedBrowserName
+  }
+
+  return 'etc'
+}

package.json

@@ -38,6 +38,7 @@
     "dist"
   ],
   "dependencies": {
+    "bowser": "^2.11.0",
     "uzip": "0.20201231.0"
   },
   "devDependencies": {

rollup.config.js

@@ -10,7 +10,8 @@ import path from 'path'
 const pkg = require('./package.json')
 const notExternal = [
   // 'pako',
-  'uzip'
+  'uzip',
+  'bowser',
 ]
 const external = Object.keys(pkg.dependencies).filter(value => !notExternal.includes(value))
 
@@ -19,7 +20,7 @@ let plugins = [
   babel(),
   terser({
     keep_fnames: true,
-    mangle: { reserved: ['CustomFile', 'CustomFileReader', 'UPNG', 'UZIP'] }
+    mangle: { reserved: ['CustomFile', 'CustomFileReader', 'UPNG', 'UZIP', 'bowser'] }
   }),
   license({
     sourcemap: true,
@@ -46,7 +47,8 @@ export default {
       sourcemap: true,
       globals: {
         // pako: 'pako',
-        uzip: 'UZIP'
+        uzip: 'UZIP',
+        bowser: 'bowser'
       }
     },
     {
@@ -55,8 +57,10 @@ export default {
       sourcemap: true,
       globals: {
         // pako: 'pako',
-        uzip: 'UZIP'
+        uzip: 'UZIP',
+        bowser: 'bowser'
       }
-    }
+    },
+
   ]
 }

test/setup_jsdom.js

@@ -8,9 +8,9 @@ if (typeof window.Worker === 'undefined') {
 }
 
 global.window = window
-const KEYS = ['document', 'Blob', 'File', 'URL', 'Worker', 'FileReader', 'atob', 'Uint8Array', 'Image', 'HTMLCanvasElement', 'HTMLImageElement']
+const KEYS = ['document', 'navigator', 'Blob', 'File', 'URL', 'Worker', 'FileReader', 'atob', 'Uint8Array', 'Image', 'HTMLCanvasElement', 'HTMLImageElement']
 KEYS.forEach(key => global[key] = window[key])
 
 if (typeof window.URL.createObjectURL === 'undefined') {
   Object.defineProperty(window.URL, 'createObjectURL', { value: () => {} })
-}
+}

yarn.lock

@@ -1219,6 +1219,11 @@ binary-extensions@^2.0.0:
   resolved "https://registry.yarnpkg.com/binary-extensions/-/binary-extensions-2.1.0.tgz#30fa40c9e7fe07dbc895678cd287024dea241dd9"
   integrity sha512-1Yj8h9Q+QDF5FzhMs/c9+6UntbD5MkRfRwac8DoEm9ZfUBZ7tZ55YcGVAzEe4bXsdQHEk+s9S5wsOKVdZrw0tQ==
 
+bowser@^2.11.0:
+  version "2.11.0"
+  resolved "https://registry.yarnpkg.com/bowser/-/bowser-2.11.0.tgz#5ca3c35757a7aa5771500c70a73a9f91ef420a8f"
+  integrity sha512-AlcaJBi/pqqJBIQ8U9Mcpc9i8Aqxn88Skv5d+xBX006BY5u8N3mGLHa5Lgppa7L/HfwgwLgZ6NYs+Ag6uUmJRA==
+
 brace-expansion@^1.1.7:
   version "1.1.11"
   resolved "https://registry.yarnpkg.com/brace-expansion/-/brace-expansion-1.1.11.tgz#3c7fcbf529d87226f3d2f52b966ff5271eb441dd"