var workflow = wp.media({
		title: 'Select the images',
		// use multiple: false to disable multiple selection
		multiple: 'add',
		button: { 
			text: 'Add selected images'
		},
		library: {
			type: 'image'
		}
	});

function getAttachment(attachment) {
	attachment = attachment.toJSON(); 
	return {id:attachment.id,url:attachment.url};
}

function select() {
	// use this to unbind the event
	// workflow.off("select");
	// get all selected images (id/url attributes only)
	console.log(workflow.state().get('selection').map(getAttachment));
}

function reset() {
	// called when dialog is closed by "close" button / "ESC" key
	// use the following line unbind the event
	// workflow.off("select");
}

// bind event handlers
workflow.on("select",select); 
workflow.on("escape",reset);

// open the dialog
workflow.open();