SO example

application.controller.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle'
});

application.template.hbs

<h1>Welcome to {{appName}}</h1>
<br>
<br>
{{thumbnail-image 
  image="https://upload.wikimedia.org/wikipedia/commons/d/d4/Wikipedesketch1.png"  
  alt="some text" 
  thumbnailWidth="40" 
  thumbnailHeight="40" 
  imageWidth="230" 
  imageHeight="230"}}
<br>
<br>

thumbnail-image.component.js

import Ember from 'ember';

export default Ember.Component.extend({
  tagName:'img',
  attributeBindings:['src','alt','width','height'],
  isThumbnail:true,
  didReceiveAttrs(){
    this.set('src',this.get('image'));
    this.set('width',this.get('thumbnailWidth'));
    this.set('height',this.get('thumbnailHeight'));
  },
  click(){
    if(this.get('isThumbnail')){
      this.set('width',this.get('imageWidth'));
      this.set('height',this.get('imageHeight'));
    } else {
      this.set('width',this.get('thumbnailWidth'));
      this.set('height',this.get('thumbnailHeight'));
    }
    this.toggleProperty('isThumbnail');  	
  }
});

twiddle.json

{
  "version": "0.6.1",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "https://cdnjs.cloudflare.com/ajax/libs/ember.js/2.3.1/ember.debug.js",
    "ember-data": "https://cdnjs.cloudflare.com/ajax/libs/ember-data.js/2.3.3/ember-data.js",
    "ember-template-compiler": "https://cdnjs.cloudflare.com/ajax/libs/ember.js/2.2.0/ember-template-compiler.js"
  }
}