YOUTUBE SOCIAL MEDIA - Virtual Reality

Video technology

YouTube primarily uses the VP9 and H.264/MPEG-4 AVC video formats, and the Dynamic Adaptive Streaming over HTTP protocol.

Playback

Previously, viewing YouTube videos on a personal computer required the Adobe Flash Player plug-in to be installed in the browser. In January 2010,

YouTube launched an experimental version of the site that used the built-in multimedia capabilities of web browsers supporting the HTML5 standard.

This allowed videos to be viewed without requiring Adobe Flash Player or any other plug-in to be installed.

The YouTube site had a page that allowed supported browsers to opt into the HTML5 trial.

Only browsers that supported HTML5 Video using the MP4 (with H.264 video) or WebM (with VP8video) formats could play the videos, and not all videos on the site were available.

On January 27, 2015, YouTube announced that HTML5 would be the default playback method on supported browsers.

YouTube used to employ Adobe Dynamic Streaming for Flash, but with the switch to HTML5 video now streams video using Dynamic Adaptive

Streaming over HTTP (MPEG-DASH), an adaptive bit-rate HTTP-based streaming solution optimizing the bitrate and quality for the available network.

Uploading

All YouTube users can upload videos up to 15 minutes each in duration. Users who have a good track record of complying with the site's Community Guidelines may be offered

the ability to upload videos up to 12 hours in length, as well as live streams, which requires verifying the account, normally through a mobile phone.

When YouTube was launched in 2005, it was possible to upload longer videos, but a ten-minute limit was introduced in March 2006 after

YouTube found that the majority of videos exceeding this length were unauthorized uploads of television shows and films.

The 10-minute limit was increased to 15 minutes in July 2010. In the past, it was possible to upload videos longer than 12 hours.

Videos can be at most 128 GB in size. Video captions are made using speech recognition technology when uploaded.

Such captioning is usually not perfectly accurate, so YouTube provides several options for manually entering the captions for greater accuracy.

YouTube accepts videos that are uploaded in most container formats, including AVI, MP4, MPEG-PS, QuickTime File Format and FLV. It supports WebM files and also 3GP, allowing videos to be uploaded from mobile phones.

Videos with progressive scanning or interlaced scanning can be uploaded but for the best video quality,

YouTube suggests interlaced videos be deinterlaced before uploading. All the video formats on YouTube use progressive scanning.

YouTube's statistics shows that interlaced videos are still being uploaded to YouTube, and there is no sign of that actually dwindling.

YouTube attributes this to uploading of made-for-TV content.

Quality and formats

YouTube originally offered videos at only one quality level, displayed at a resolution of 320×240 pixels using the Sorenson Spark codec (a variant of H.263), with mono MP3 audio.

In June 2007, YouTube added an option to watch videos in 3GP format on mobile phones. In March 2008, a high-quality mode was added, which increased the resolution to 480×360 pixels.

In November 2008, 720p HD support was added. At the time of the 720p launch, the YouTube player was changed from a 4:3 aspect ratio to a widescreen 16:9.

With this new feature, YouTube began a switchover to H.264/MPEG-4 AVCas its default video compression format. In November 2009, 1080p HD support was added.

In July 2010, YouTube announced that it had launched a range of videos in 4K format, which allows a resolution of up to 4096×3072 pixels.

In June 2015, support for 8K resolution was added, with the videos playing at 7680×4320 pixels. In November 2016, support for HDR video

was added which can be encoded with Hybrid Log-Gamma (HLG) or Perceptual Quantizer (PQ). HDR video can be encoded with the Rec. 2020 color space.

In June 2014, YouTube introduced videos playing at 60 frames per second, in order to reproduce video games with a frame rate comparable to high-end graphics cards. The videos playback at a resolution of 720p or higher.

YouTube videos are available in a range of quality levels. The former names of standard quality (SQ), high quality (HQ), and high definition (HD) have been replaced by numerical values representing the vertical resolution of the video.

The default video stream is encoded in the VP9 format with stereo Opus audio; if VP9/WebM is not supported in the browser/device or the browser's user agent reports Windows XP, then H.264/MPEG-4 AVC video with stereo AAC audio is used instead.

Live streaming

YouTube carried out early experiments with live streaming, including a concert by U2 in 2009, and a question-and-answer session with US President Barack Obama in February 2010.

These tests had relied on technology from 3rd-party partners, but in September 2010, YouTube began testing its own live streaming infrastructure.

In April 2011, YouTube announced the rollout of YouTube Live, with a portal page at the URL "www.youtube.com/live". The creation of live streams was initially limited to select partners.

It was used for real-time broadcasting of events such as the 2012 Olympics in London. In October 2012, more than 8 million people watched Felix Baumgartner's jump from the edge of space as a live stream on YouTube.

In May 2013, the creation of live streams was opened to verified users with at least 1,000 subscribers; in August of that year the number was reduced to 100 subscribers, and in

December the limit was removed. In February 2017, live streaming was introduced to the official

YouTube mobile app. Live streaming via mobile was initially restricted to users with at least 10,000 subscribers, but as of mid-2017 it has been reduced to 100 subscribers.

Live streams can be up to 4K resolution at 60 fps, and also support 360° video. In February 2017, a live streaming feature called

Super Chat was introduced, which allows viewers to donate between $1 and $500 to have their comment highlighted.

3D videos

In a video posted on July 21, 2009,[111] YouTube software engineer Peter Bradshaw announced that YouTube users can now upload 3D videos.

The videos can be viewed in several different ways, including the common anaglyph (cyan/red lens) method which utilizes glasses worn by the viewer to achieve the 3D effect.

The YouTube Flash player can display stereoscopic content interleaved in rows, columns or a checkerboard pattern,

side-by-side or anaglyph using a red/cyan, green/magenta or blue/yellow combination. In May 2011, an HTML5 version of the

YouTube player began supporting side-by-side 3D footage that is compatible with Nvidia 3D Vision.

360-degree videos

In January 2015, Google announced that 360-degree video would be natively supported on YouTube. On March 13, 2015, YouTube-enabled 360° videos which can be viewed from Google Cardboard, a virtual reality system.

YouTube 360 can also be viewed from all other virtual reality headsets. Live streaming of 360° video at up to 4K resolution is also supported.

In 2017, YouTube began to promote an alternative stereoscopic video format known as VR180, which is limited to a 180-degree field of view but is

promoted as being easier to produce than 360-degree video and allowing more depth to be maintained by not subjecting the video to equirectangular projection

User features

Community

On September 13, 2016, YouTube launched a public beta of Community, a social media-based feature that allows users to post text, images (including GIFs), live videos and others in a separate "Community" tab on their channel.

Prior to the release, several creators had been consulted to suggest tools Community could incorporate that they would find useful; these

YouTubers included Vlogbrothers, AsapScience, Lilly Singh, The Game Theorists, Karmin, The Key of Awesome, The Kloons, Peter Hollens, Rosianna Halse Rojas, Sam Tsui, Threadbanger, and Vsauce3.

Content accessibility

YouTube offers users the ability to view its videos on web pages outside their website. Each YouTube video is accompanied by a piece of HTML that can be used to embed it on any page on the Web.

This functionality is often used to embed YouTube videos in social networking pages and blogs.

Users wishing to post a video discussing, inspired by or related to another user's video are able to make a "video response".

On August 27, 2013, YouTube announced that it would remove video responses for being an underused feature.

Embedding, rating, commenting and response posting can be disabled by the video owner.

YouTube does not usually offer a download link for its videos and intends for them to be viewed through its website interface. A small number of videos can be downloaded as MP4 files.

Numerous third-party websites, applications, and browser plug-ins allow users to download YouTube videos. In February 2009,

YouTube announced a test service, allowing some partners to offer video downloads for free or for a fee paid through Google Checkout.

In June 2012, Google sent cease and desist letters threatening legal action against several websites offering online download and conversion of

YouTube videos. In response, Zamzar removed the ability to download YouTube videos from its site.

Users retain copyright of their own work but have the option to grant certain usage rights under any public copyright license they choose.

Since July 2012, it has been possible to select a Creative Commons license as the default, allowing other users to reuse and remix the material.

Platforms

Most modern smartphones are capable of accessing YouTube videos, either within an application or through an optimized website. YouTube Mobile was launched in June 2007, using RTSP streaming for the video.

Not all of YouTube's videos are available on the mobile version of the site. Since June 2007, YouTube's videos have been available for viewing on a range of Apple products.

This required YouTube's content to be transcoded into Apple's preferred video standard, H.264, a process that took several months. YouTube videos can be viewed on devices including Apple TV, iPod Touch, and the iPhone.

In July 2010, the mobile version of the site was relaunched based on HTML5, avoiding the need to use Adobe Flash Player and optimized for use with touchscreen controls.

The mobile version is also available as an app for the Android platform. In September 2012, YouTube launched its first app for the iPhone, following the decision to drop YouTube as one of the preloaded apps in the iPhone 5 and iOS 6 operating system. According to GlobalWebIndex, YouTube was used by 35% of smartphone users between April and June 2013, making it the third most used app.

A TiVo service update in July 2008 allowed the system to search and play YouTube videos. In January 2009, YouTube launched "YouTube for TV", a version of the website tailored for set-top boxes and other TV-based media devices with web browsers, initially allowing its videos to be viewed on the PlayStation 3 and Wii video game consoles.

In June 2009, YouTube XL was introduced, which has a simplified interface designed for viewing on a standard television screen. YouTube is also available as an app on Xbox Live. On November 15, 2012, Google launched an official app for the Wii, allowing users to watch YouTube videos from the Wii channel.

An app is also available for Wii U and Nintendo 3DS, and videos can be viewed on the Wii U Internet Browser using HTML5. Google made YouTube available on the Roku player on December 17, 2013, and, in October 2014, the Sony PlayStation 4.

Localization

On June 19, 2007, Google CEO Eric Schmidt was in Paris to launch the new localization system. The interface of the website is available with localized versions in 89 countries, one territory (Hong Kong) and a worldwide version.

Countries with YouTube localization show

The YouTube interface suggests which local version should be chosen on the basis of the IP address of the user. In some cases, the message "This video is not available in your country" may appear because of copyright restrictions or inappropriate content. The interface of the

YouTube website is available in 76 language versions, including Amharic, Albanian, Armenian, Bengali, Burmese, Khmer, Kyrgyz, Laotian, Mongolian, Persian and Uzbek, which do not have local channel versions. Access to YouTube was blocked in Turkey between 2008 and 2010, following controversy over the posting of videos deemed insulting to Mustafa Kemal Atatürk and some material offensive to Muslims.

In October 2012, a local version of YouTube was launched in Turkey, with the domain youtube.com.tr. The local version is subject to the content regulations found in Turkish law. In March 2009, a dispute between YouTube and the British royalty collection agency PRS for Music led to premium music videos being blocked for

YouTube users in the United Kingdom. The removal of videos posted by the major record companies occurred after failure to reach agreement on a licensing deal. The dispute was resolved in September 2009. In April 2009, a similar dispute led to the removal of premium music videos for users in Germany