Skip to main content

Day 89 of 100DaysOfSpec, param and video elements

I am reading and taking notes on the HTML specifications for 100 days as part of #The100DayProject. Read the initial intent/backstory. I am a Microsoft employee but all opinions, comments, etc on this site are my own. I do not speak on behalf of my employer, and thus no comments should be taken as representative of Microsoft's official opinion of the spec. Subsections not listed below were read without comment.

Currently reading in 4.7 Embedded content

UAs = user agents = browsers, etc.

4.7.5 The param element

“The param element defines parameters for plugins invoked by object elements. It does not represent anything on its own.”

  • Is a child of an object element, before flow content.
  • Both possible attributes (name and value) need to be applied. Either one can have any value! When this condition is met, the param defines a parameter for its parent object element.
  • You can have any number of param elements as children of object elements (0+).

4.7.6 The video element

“A video element is used for playing videos or movies, and audio files with captions.”

Attributes besides globals:

  • src
  • crossorigin: how it handles requests from other origins
  • poster: frame to show before the video plays. Pretty neat. Value is a URL.
  • preload: “hints how much buffering the media resource will likely need”
  • autoplay: whether the video can be played on page load. The word used in the spec is “hint”. Which means that the UA has flexibility in whether or not to honor the autoplay…
  • mediagroup “groups media elements together with an implicit MediaController”
  • loop: boolean
  • muted: also a boolean
  • controls: show UA controls
  • width
  • height
  • Only one ARIA role available: application.
  • Fallback content is allowed for old browsers. Specifically not meant to fix accessibility (a11y) problems.

Strategies for a11y

  • Captions embedded in the video or in external files using the track element
  • Sign-language tracks embedded or provided in additional synced-up video elements
  • Audio descriptions, embedded in video, or in an audio element “slaved” to the video element. And here we have bias baked into technical jargon. -__-
  • Text in a WebVTT file referenced by a track element, “synthesized” into speech by the UA. This tech can also provide chapter titles.
  • Can also link to or display text transcripts close to the video element.


My blog uses Webmentions. Responses from Mastodon and other sites that send Webmentions will show up here.

No Webmentions have been sent to this post yet.