Image fetch in Gallery

function imgFetchMedia(){
  var querycontext = {mimetype:"image/*"};
  var Status = kony.phone.openMediaGallery(onselectioncallback, querycontext);

  function onselectioncallback(rawBytes)
  {


    if (rawBytes === null){
      alert("please select images");
    }else{
      var base64Str = kony.convertToBase64(rawBytes);
      frmRegistor.imageshow.base64 = base64Str;

      frmDetailofRegistor.imageofuser.base64 = base64Str;
    }

  }

}