Source : http://www.alsacreations.com/article/lire/1125-introduction-balise-video-html5-mp4-h264-webm-ogg-theora.html

Mon code :

<video controls="controls" width="640" height="480">
    <source src="img/lightbox/full-size/animationcompleteV3.mp4" type="video/mp4" />
    <source src="img/lightbox/full-size/animationcompleteV3.webmsd.webm" type="video/webm" />
    <source src="img/lightbox/full-size/animationcompleteV3.oggtheora.ogv" type="video/ogv" />
    <a href="img/lightbox/full-size/animationcompleteV3.mp4">Animation déménagement Bleu Banquise (66 Mo)</a>
</video>

Tester ça : https://github.com/sampotts/plyr