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HTML video is a subject of the HTML specification as the standard way of playing video via the web. Introduced in HTML5, it is designed to partially replace the object element and the previous de facto standard of using the proprietary Adobe Flash plugin, though early adoption was hampered by lack of agreement as to which video coding formats and audio coding formats should be supported in web browsers. As of 2020, HTML video is the only widely supported video playback technology in modern browsers, with the Flash plugin being phased out. History of <video> element The <video> element started being discussed by the WHATWG in October 2006. The <video> element was proposed by Opera Software in February 2007. Opera also released a preview build that was showcased the same day, and a manifesto that called for video to become a first-class citizen of the web. <video> element examples The following HTML code fragment will embed a WebM video into a web page. The "controls" attribute enables the browser's own user interface for controlling playback. Alternatively, playback can be controlled with JavaScript, which the web designer can use to create a custom user interface. The optional "poster" attribute specifies an image to show in the video's place before playback is started. Its purpose is to be representative of the video. Multiple sources Video format support varies among browsers (see below), so a web page can provide video in multiple formats. For other features, browser sniffing is used sometimes, which may be error-prone: any web developer's knowledge of browsers will inevitably be incomplete or not up-to-date. The browser in question "knows best" what formats it can use. The "video" element supports fallback through specification of multiple sources. Using any number of <source> elements, as shown below, the browser will choose automatically which file to download. Alternatively, the JavaScript canPlayType() function can be used to achieve the same. The "type" attribute specifies the MIME type and possibly a list of codecs, which helps the browser to determine whether it can decode the file without beginning to download it. The MIME type denotes the container format of the file, and the container format defines the interpretation of the codec string. Supported video and audio formats The HTML specification does not specify which video and audio formats browsers should support. User agents are free to support any video formats they feel are appropriate, but content authors cannot assume that any video will be accessible by all complying user agents, since user agents have no minimal set of video and audio formats to support. The HTML5 Working Group considered it desirable to specify at least one video format which all user agents (browsers) should support. The ideal format in this regard would: Have good compression, good image quality, and low decode processor use. Be royalty-free. In addition to software decoders, a hardware video decoder should exist for the format, as many embedded processors do not have the performance to decode video. Initially, Ogg Theora was the recommended standard video format in HTML5, because it was not affected by any known patents. But on 10 December 2007, the HTML5 specification was updated, replacing the reference to concrete formats: User agents should support Theora video and Vorbis audio, as well as the Ogg container format. with a placeholder: It would be helpful for interoperability if all browsers could support the same codecs. However, there are no known codecs that satisfy all the current players: we need a codec that is known to not require per-unit or per-distributor licensing, that is compatible with the open source development model, that is of sufficient quality as to be usable, and that is not an additional submarine patent risk for large companies. This is an ongoing issue and this section will be updated once more information is available. The result was a polarisation of HTML video between industry-standard, ISO-defined but patent-encumbered formats, and open formats. The new AV1 format by Alliance for Open Media aims to be both industry standard, royalty-free, and open, and has wide industry support. Free formats Although Theora is not affected by known non-free patents, Apple has expressed concern about unknown patents that might affect it, whose owners might be waiting for a corporation with extensive financial resources to use the format before suing. Formats like H.264 might also be subject to unknown patents in principle, but they have been deployed much more widely and so it is presumed that any patent-holders would have already made themselves known. Apple has also opposed requiring Ogg format support in the HTML standard (even as a "should" requirement) on the grounds that some devices might support other formats much more easily, and that HTML has historically not required particular formats for anything. Some web developers criticized the removal of the Ogg formats from the specification. A follow-up discussion also occurred on the W3C questions and answers blog. Mozilla and Opera support only the open formats of Theora and WebM. Google stated its intention to remove support for H.264 in 2011, specifically for the HTML video tag. Although it has been removed from Chromium, as of January 2021 it has yet to be removed from Google Chrome ten years later. MPEG-DASH Support via the Media Source Extensions (MSE) The adaptive bitrate streaming standard MPEG-DASH can be used in Web browsers via the Media Source Extensions (MSE) and JavaScript-based DASH players. Such players are, e.g., the open-source project dash.js of the DASH Industry Forum, but there are also products such as the HTML5 Video Player of Bitmovin (using HTML with JavaScript, but also a Flash-based DASH players for legacy Web browsers not supporting the MSE). Google's purchase of On2 Google's acquisition of On2 in 2010 resulted in its acquisition of the VP8 video format. Google has provided a royalty-free license to use VP8. Google also started WebM, which combines the standardized open source VP8 video codec with Vorbis audio in a Matroska based container. The opening of VP8 was welcomed by the Free Software Foundation. When Google announced in January 2011 that it would end native support of H.264 in Chrome, criticism came from many quarters including Peter Bright of Ars Technica and Microsoft web evangelist Tim Sneath, who compared Google's move to declaring Esperanto the official language of the United States. However, Haavard Moen of Opera Software strongly criticized the Ars Technica article and Google responded to the reaction by clarifying its intent to promote WebM in its products on the basis of openness. After the launch of WebM, Mozilla and Opera have called for the inclusion of VP8 in HTML. On 7 March 2013, Google Inc. and MPEG LA, LLC announced agreements covering techniques that "m.... Discover the Chris Minnick popular books. Find the top 100 most popular Chris Minnick books.