var currentImg = -1;

function scrollDown() {
    var elem = document.getElementById("middleContainer");
    elem.scrollTop += 40;
  }
function scrollUp() {
    var elem = document.getElementById("middleContainer");
    if (elem.scrollTop < 40) {
      elem.scrollTop = 0;
    } else {
      elem.scrollTop -= 40;
    }
}

function refreshCaptcha(img) {
	var image = img.src + "?x=" + Math.random();
	img.src = image;
}

function submitForm() {
	document.forms[0].submit();
}

function preloadImages() {
      for (var i=0; i < imgs.length; i++) {
        var im = new Image();
        im.src = imgs[i].src;
      }
      changeImage();
    }


function changeImage() {
      if (currentImg == imgs.length - 1) {
        currentImg = 0;
      } else {
        currentImg++;
      }
      /*console.log(currentImg);*/
      var img = document.getElementById('pic');
      img.src = imgs[currentImg].src;
      var descriptionDiv = document.getElementById('descriptionContainer');
      if (descriptionDiv) {
        descriptionDiv.innerHTML = imgs[currentImg].description;
      }
      setTimeout('changeImage()', 4000);
    }