How to show full resolution image at clicking on thumnail

var epsg4326 = new OpenLayers.Projection("EPSG:4326");
var OSVMain = (function() {
var map, markers, map_move_timeout;
var photos = {};
function mapChange() {
if( map_move_timeout )
clearTimeout(map_move_timeout);
map_move_timeout = setTimeout(mapChangeTimeout, 500);
updateLinks();
}
function updateLinks() {
var center = OSV.getMapCenter(map);
var zoom = map.getZoom();
$('#permalink').attr('href',OSV.getURLBase()+'?lat ='+center.lat+'&lon='+center.lon+'&zoom='+zoom);
$('#kmllink').attr('href',getLocateLink('kml'));
}
function getLocateLink(format) {
var extent = OSV.getMapExtent(map);
var url = OSV.getURLBase()+'/api/photos/locate.'+format+'?bbox=';
url += [ extent.left, extent.bottom, extent.right, extent.top].join(',');
return url;
}
function mapChangeTimeout() {
map_move_timeout = null;
var url = getLocateLink('json');
$.get( url, null, photosLoaded, 'json' );
}
function photosLoaded(json) {
var new_photos = {};
var size = new OpenLayers.Size(50, 50);
var offset = new OpenLayers.Pixel(-25, -25);
for( var i = 0, l = json.length; i < l; ++i ) {
var p = new OSVPhoto(json[i]);
if( photos[p.data.id] ) {
new_photos[p.data.id] = photos[p.data.id];
photos[p.data.id] = null;
} else {
var position = new OpenLayers.LonLat(p.data.lon,p.data.lat);
var icon = new OpenLayers.Icon(p.url('square'), size, offset);
p.marker = new OpenLayers.Marker(position.clone().transform(epsg4 326, map.getProjectionObject()), icon);
new_photos[p.data.id] = p;
markers.addMarker(p.marker);

}
}
for( var k in photos ) {
var p = photos[k];
if( p && p.marker )
markers.removeMarker(p.marker);
}
photos = new_photos;
}
function setup() {
var vectors;
var popup;

map = new OpenLayers.Map($('#map').get(0), {
controls: [
new OpenLayers.Control.ArgParser(),
new OpenLayers.Control.Attribution(),
new OpenLayers.Control.LayerSwitcher(),
new OpenLayers.Control.Navigation(),
new OpenLayers.Control.PanZoomBar()
],
units: "m",
maxResolution: 156543.0339,
numZoomLevels: 20,
displayProjection: new OpenLayers.Projection("EPSG:4326")
});

var mapnik = new OpenLayers.Layer.OSM.Mapnik("Mapnik", {
displayOutsideMaxExtent: true,
wrapDateLine: true
});
map.addLayer(mapnik);

var osmarender = new OpenLayers.Layer.OSM.Osmarender("Osmarender", {
displayOutsideMaxExtent: true,
wrapDateLine: true
});
map.addLayer(osmarender);

var numZoomLevels = Math.max(mapnik.numZoomLevels, osmarender.numZoomLevels);

var start = OSV.getStartLocation();
var numzoom = map.getNumZoomLevels();
if (start.zoom >= numzoom) start.zoom = numzoom - 1;
map.setCenter(start.pos.clone().transform(epsg4326 , map.getProjectionObject()), start.zoom);
OSV.setupMapEventHandlers(map);
map.events.register("moveend", map, mapChange);
map.events.register("zoomend", map, mapChange);
mapChange();
markers = new OpenLayers.Layer.Markers("Markers", {
displayInLayerSwitcher: false,
numZoomLevels: numZoomLevels,
maxExtent: new OpenLayers.Bounds(-20037508,-20037508,20037508,20037508),
maxResolution: 156543,
units: "m",
projection: "EPSG:900913"
});
map.addLayer(markers);

}
return {
setup: setup,
1:1
};
})();
$(function(){
OSVMain.setup();
});