function hideAll() {
    document.itemDetailsBlock = document.getElementById("thumbnail-photos");
    document.itemDetails = document.itemDetailsBlock.getElementsByTagName("img");
    for (var ti=0;ti<document.itemDetails.length;ti++) {
        var itemDetail = document.itemDetails[ti];
        itemDetail.className = "inactive";
    }
}

function showPhoto(ID) {
    hideAll();
    document.getElementById("thumbnail-photo-"+ID).className = "active";
    document.getElementById("large-photo").src = "images/gallery/" + gallery + "-" + ID + "-lg.jpg";
}