owl.on('changed.owl.carousel', function(event) {
...
})function callback(event) {
// Provided by the core
var element = event.target; // DOM element, in this example .owl-carousel
var name = event.type; // Name of the event, in this example dragged
var namespace = event.namespace; // Namespace of the event, in this example owl.carousel
var items = event.item.count; // Number of items
var item = event.item.index; // Position of the current item
// Provided by the navigation plugin
var pages = event.page.count; // Number of pages
var page = event.page.index; // Position of the current page
var size = event.page.size; // Number of items per page
}