var done=false;
function launchViewer(filename,x)
 {
 if (!done)
 {       
    if ( x == 375)
        {
            window.imagex=x;
            window.imagename=filename;
            viewer=window.open('bigview.html','VIEWER','scrollbars=yes,status=no,resizable=yes,width=460,height=590');
            viewer.opener=window;
            viewer.focus();
        }
     else
        {
        window.imagex=x;
            window.imagename=filename;
            viewer=window.open('bigview.html','VIEWER','scrollbars=yes,status=no,resizable=yes,width=550,height=460');
            viewer.opener=window;
            viewer.focus();
        }   
 }
 return done;
 }