support animated GIF

ui/file_manager/gallery/js/image_editor/filter.js

Index: ui/file_manager/gallery/js/image_editor/filter.js
diff --git a/ui/file_manager/gallery/js/image_editor/filter.js b/ui/file_manager/gallery/js/image_editor/filter.js
index a68fff846ab1fd2ef40eea0fb908892b1f1a923d..fdb71c062140d42ecbd6e2267a7492c1ecbbef5f 100644
--- a/ui/file_manager/gallery/js/image_editor/filter.js
+++ b/ui/file_manager/gallery/js/image_editor/filter.js
@@ -26,30 +26,50 @@ filter.create = function(name, options) {
 };
 
 /**
+ * Ensures argument is canvas. If it's not, creates new canvas and copy.
+ *
+ * @param {!HTMLCanvasElement|!HTMLImageElement} imgOrCanvas
+ *    imageOrCanvas
+ * @return {!HTMLCanvasElement} canvas.

[yawano, 2016/01/20 06:23:09]

nit: @private

[ryoh, 2016/01/21 03:19:55]

Done.

+ */
+filter.ensureCanvas_ = function(imgOrCanvas) {
+  if(imgOrCanvas.tagName === 'canvas') {
+    return assertInstanceof(imgOrCanvas, HTMLCanvasElement);
+  }
+  var canvas = assertInstanceof(document.createElement('canvas'),
+      HTMLCanvasElement);
+  canvas.width = imgOrCanvas.width;
+  canvas.height = imgOrCanvas.height;
+  var context = canvas.getContext('2d');
+  context.drawImage(imgOrCanvas, 0, 0);
+  return canvas;
+};
+
+/**
  * Apply a filter to a image by splitting it into strips.
  *
  * To be used with large images to avoid freezing up the UI.
  *
  * @param {!HTMLCanvasElement} dstCanvas Destination canvas.
- * @param {!HTMLCanvasElement} srcCanvas Source canvas.
+ * @param {!HTMLCanvasElement|!HTMLImageElement} srcImage Source image.
  * @param {function(!ImageData,!ImageData,number,number)} filterFunc Filter.
  * @param {function(number, number)} progressCallback Progress callback.
  * @param {number=} opt_maxPixelsPerStrip Pixel number to process at once.
  */
 filter.applyByStrips = function(
-    dstCanvas, srcCanvas, filterFunc, progressCallback, opt_maxPixelsPerStrip) {
+    dstCanvas, srcImage, filterFunc, progressCallback, opt_maxPixelsPerStrip) {
   // 1 Mpix is a reasonable default.
   var maxPixelsPerStrip = opt_maxPixelsPerStrip || 1000000;
 
   var dstContext = dstCanvas.getContext('2d');
-  var srcContext = srcCanvas.getContext('2d');
-  var source = srcContext.getImageData(0, 0, srcCanvas.width, srcCanvas.height);
+  var srcContext = filter.ensureCanvas_(srcImage).getContext('2d');
+  var source = srcContext.getImageData(0, 0, srcImage.width, srcImage.height);
 
-  var stripCount = Math.ceil(srcCanvas.width * srcCanvas.height /
+  var stripCount = Math.ceil(srcImage.width * srcImage.height /
       maxPixelsPerStrip);
 
   var strip = srcContext.getImageData(0, 0,
-      srcCanvas.width, Math.ceil(srcCanvas.height / stripCount));
+      srcImage.width, Math.ceil(srcImage.height / stripCount));
 
   var offset = 0;