function convertImgToBase64(url)
{
    var canvas = document.createElement('canvas');
    var ctx = canvas.getContext('2d');
    img = document.createElement('img'),
    img.src = url;
    canvas.height = img.height;
    canvas.width = img.width;
    var dataURL = canvas.toDataURL('image/jpeg')
    alert(dataURL);
    canvas = null; 
    return dataURL;
  }
var imageurl = 'http://qph.is.quoracdn.net/main-qimg-ca033a73e2ea858908c44905d4c25f4b?convert_to_webp=true';
var som =convertImgToBase64(imageurl);
doc.addImage(som, 'JPEG', 15, 40, 180, 180);
doc.output('datauristring');
but nothing happens no pdf is generated ? I am getting the correct base64 code in alert box but image is not generated?
 
     
     
    