SOURCE

var canvas = document.getElementById('myCanvas');
var context = canvas.getContext('2d');
var imageObj = new Image();
imageObj.src = 'http://static2.wikia.nocookie.net/__cb20120812082361/adventuretimewithfinnandjake/images/0/06/Pig_trans.png';
var pigs = [];
for(var i = 0; i < 200; i++)
{        pigs.push({scale:Math.random()*100,y:Math.random()*450,x:Math.random()*1000});            
}
pigs.sort(function(a, b) {
    return a.scale - b.scale;
});
            
function update()
{
  context.clearRect(0,0,1000,500); 
  for(var i=0;i<pigs.length;i++)
  {
      context.restore();
      pigs[i].x += .1 * pigs[i].scale;
      context.drawImage(imageObj, (pigs[i].x%1300) - 300, pigs[i].y + Math.sin(pigs[i].x/100) * 15,pigs[i].scale,pigs[i].scale);
  }  
}
setInterval(update,1000/60);

<canvas id="myCanvas" width="1000" height="500" style="background-color:black;"></canvas>

body {
        margin: 0px;
        padding: 0px;
      }