XML tag count in PHP

<videos><video><title1>Title1</title1><title2>Title2</title2><title3>Title3</title3><title4>Title4</title4><desc> desc</desc><img> img</img></video><video><title1>Title1</title1><title2>Title2</title2><title3>Title3</title3><desc> desc</desc><img> img</img></video><video><title1>Title1</title1><title2>Title2</title2><title3>Title3</title3> <title4>Title3</title4> <title5>Title3</title5><desc> desc</desc><img> img</img></video></videos>

I have this type of xml. I want to count titles into one video tag.

also want to create text slide show. How can i do it?

Thanks for help.