var cur

function ch(what, src, video) {

    if (video == 'false') {
        document.getElementById('photo').className = 'display';
        document.getElementById('video').className = 'displaynot';
        if (typeof (what) == 'string') what = document.getElementById(what);
        if (cur) cur.className = '';
        cur = what;
        what.className = 'current';

        document.getElementById('Preview').href = src + '?h=800';
        document.getElementsByName('LargeImage')[0].src = src + '?h=400';

        fb.tagOneAnchor(document.getElementById('Preview'));
    }
    if (video == 'true') {
        document.getElementById('photo').className = 'displaynot';
        document.getElementById('video').className = 'display';
        if (cur) cur.className = '';
        cur = what;
        what.className = 'current';
    }

}