Please be aware that there must be a legitimate image for the poster image. For some reason, the autoplay parameter will be ignored, my theory behind this is autoplay is only supported with mp4 or mov files and not streaming files. This must be enclosed in script tags and it should be put in the body of an html document.
Wherever you place the code is where the object will appear. For some reason I had no luck in running this in Firefox, this is probably because the particular stream I was using used the H.264 codec which Mozilla is apparently prohibited to use because of its open-source nature. However, it worked well in Safari and in Chrome.