function galeria() 
{
    var index1 = document.getElementById('select1').selectedIndex;
    var value1 = document.getElementById('select1').options[index1].value;
    var index2 = document.getElementById('select2').selectedIndex;
    var value2 = document.getElementById('select2').options[index2].value;
    document.getElementById('picture').src = "pictures/" + value1 + "/" + value2 + ".jpg"

}