Streaming media is multimedia that is constantly received by and presented to an end-user while being delivered by a provider. The verb "to stream" refers to the process of delivering or obtaining media in this manner; the term refers to the delivery method of the medium, rather than the medium itself, and is an alternative to file downloading, a process in which the end-user obtains the entire file for the content before watching or listening to it.
A client end-user can use their media player to start playing the data file (such as a digital file of a movie or song) before the entire file has been transmitted. Distinguishing delivery method from the media distributed applies specifically to telecommunications networks, as most of the delivery systems are either inherently streaming (e.g. radio, television, streaming apps) or inherently non-streaming (e.g. books, Videotape, audio Compact Disc). For example, in the 1930s, elevator music was among the earliest popularly available streaming media; nowadays Internet television is a common form of streamed media. The term "streaming media" can apply to media other than video and audio such as live closed captioning, ticker tape, and real-time text, which are all considered "streaming text".
The term "streaming" was first used for tape drives made by Data Electronics Inc. for drives meant to slowly ramp up and run for the entire track; the slow ramp times resulted in lower drive costs, making a more competitive product. "Streaming" was applied in the early 1990s as a better description for video on demand and later live video on IP networks first by Starlight Networks for video streaming and Real Networks for audio streaming; at the time such video was usually referred to as "store and forward video", which was misleading nomenclature.
Live media is the delivery of Internet content in real-time, as events happen, much as live television broadcasts its contents over the airwaves via a television signal. Live internet streaming requires a form of source media (e.g. a video camera, an audio interface, screen capture software), an encoder to digitize the content, a media publisher, and a content delivery network to distribute and deliver the content. Live streaming does not need to be recorded at the origination point, although it frequently is.
Streaming generally refers to the situation where a user watches digital video content or listens to digital audio content on a computer screen and speakers (ranging from a smartphone, through a desktop computer to a large-screen home cinema) over the Internet. With streaming content, the user does not have to download the entire digital video or digital audio file before they start to play it.
There are challenges with streaming content on the Internet. If the user does not have enough bandwidth in their Internet connection, they may experience stops in the content and some users may not be able to stream certain content due to not having compatible computer or software systems.
Some popular streaming services are the video sharing website YouTube; Twitch and Mixer, which live stream the playing of video games; Netflix and Amazon Video, which stream Film and Television show; and Spotify, Apple Music and TIDAL, which stream music.
Microsoft Research developed a Microsoft TV application which was compiled under MS Windows Studio Suite and tested in conjunction with Connectix QuickCam. RealNetworks was also a pioneer in the streaming media markets, when it broadcast a baseball game between the New York Yankees and the Seattle Mariners over the Internet in 1995. The first symphonic concert on the Internet took place at the Paramount Theater in Seattle, Washington on November 10, 1995. The concert was a collaboration between The Seattle Symphony and various guest musicians such as Slash (Guns 'n Roses, Velvet Revolver), Matt Cameron (Soundgarden, Pearl Jam), and Barrett Martin (Screaming Trees). When Word Magazine launched in 1995, they featured the first-ever streaming soundtracks on the Internet.
Metropolitan Opera Live in HD is a program in which the Metropolitan Opera streams an opera performance "live", as the performance is taking place. In 2013–2014, 10 operas were transmitted via satellite into at least 2,000 theaters in 66 countries.Pamela McClintock, "Met Opera Standoff Threatens $60 Million Theater Business", The Hollywood Reporter (online), August 7, 2014 on hollywoodreporter.com
Microsoft developed a media player known as ActiveMovie in 1995 that allowed streaming media and included a proprietary streaming format, which was the precursor to the streaming feature later in Windows Media Player 6.4 in 1999. In June 1999 Apple also introduced a streaming media format in its QuickTime 4 application. It was later also widely adopted on websites along with RealPlayer and Windows Media streaming formats. The competing formats on websites required each user to download the respective applications for streaming and resulted in many users having to have all three applications on their computer for general compatibility.
In 2000 Industryview.com launched its "world's largest streaming video archive" website to help businesses promote themselves. Webcasting became an emerging tool for business marketing and advertising that combined the immersive nature of television with the interactivity of the Web. The ability to collect data and feedback from potential customers caused this technology to gain momentum quickly.
Around 2002, the interest in a single, unified, streaming format and the widespread adoption of Adobe Flash prompted the development of a video streaming format through Flash, which was the format used in Flash-based players on many popular video hosting sites, such as YouTube, now defaulting to HTML5 video. Increasing consumer demand for live streaming has prompted YouTube to implement a new live streaming service to users. Presently the company also offers a (secured) link returning the available connection speed of the user.
The Recording Industry Association of America (RIAA) revealed through its 2015 earnings report that streaming services were responsible for 34.3 percent of the year's total music industry's revenue, growing 29 percent from the previous year and becoming the largest source of income, pulling in around $2.4 billion. US streaming revenue grew 57 percent to $1.6 billion in the first half of 2016 and accounted for almost half of industry sales.
As of 2016, a media stream can be streamed either "live" or "on demand". Live streams are generally provided by a means called "true streaming". True streaming sends the information straight to the computer or device without saving the file to a hard disk. On-demand streaming is provided by a means called progressive streaming or progressive download. Progressive streaming saves the file to a hard disk and then is played from that location. On-demand streams are often saved to hard disks and servers for extended amounts of time; while the live streams are only available at one time only (e.g., during the football game).Grant and Meadows. (2009). Communication Technology Update and Fundamentals 11th Edition. pp.114 Streaming media is increasingly being coupled with use of social media. For example, sites such as YouTube encourage social interaction in webcasts through features such as live chat, , user posting of comments online and more. Furthermore, streaming media is increasingly being used for social business and e-learning. Due the popularity of the streaming medias, many developers have introduced free HD movie streaming apps for the people who use smaller devices such as tablets and smartphones for everyday purposes.
The Horowitz Research State of Pay TV, OTT and SVOD 2017 report said that 70 percent of those viewing content did so through a streaming service, and that 40 percent of TV viewing was done this way, twice the number from five years earlier. Millennials, the report said, streamed 60 percent of content.
If the file is stored on a server for on-demand streaming and this stream is viewed by 1,000 people at the same time using a Unicast protocol, the requirement is 300 kbit/s × 1,000 = 300,000 kbit/s = 300 Mbit/s of bandwidth. This is equivalent to around 135 gigabyte per hour. Using a multicast protocol the server sends out only a single stream that is common to all users. Therefore, such a stream would only use 300 kbit/s of serving bandwidth. See below for more information on these protocols. The calculation for live streaming is similar. Assuming that the seed at the encoder is 500 kbit/s and if the show lasts for 3 hours with 3,000 viewers, then the calculation is number of Megabyte transferred = encoder speed (in bit/s) × number of seconds × number of viewers / (8*1024*1024). The results of this calculation are as follows: number of Megabyte transferred = 500 x 1024 (bit/s) × 3 × 3,600 ( = 3 hours) × 3,000 (number of viewers) / (8*1024*1024) = 1,977,539 Megabyte
Another approach that seems to incorporate both the advantages of using a standard web protocol and the ability to be used for streaming even live content is adaptive bitrate streaming. HTTP adaptive bitrate streaming is based on HTTP progressive download, but contrary to the previous approach, here the files are very small, so that they can be compared to the streaming of packets, much like the case of using RTSP and RTP.Ch. Z. Patrikakis, N. Papaoulakis, Ch. Stefanoudaki, M. S. Nunes, "Streaming content wars: Download and play strikes back" presented at the Personalization in Media Delivery Platforms Workshop, 218, Venice, Italy, 2009. Reliable protocols, such as the Transmission Control Protocol (TCP), guarantee correct delivery of each bit in the media stream. However, they accomplish this with a system of timeouts and retries, which makes them more complex to implement. It also means that when there is data loss on the network, the media stream stalls while the protocol handlers detect the loss and retransmit the missing data. Clients can minimize this effect by buffering data for display. While delay due to buffering is acceptable in video on demand scenarios, users of interactive applications such as video conferencing will experience a loss of fidelity if the delay caused by buffering exceeds 200 ms.Krasic, C. and Li, K. and Walpole, J., The case for streaming multimedia with TCP, Lecture Notes in Computer Science, pages 213--218, Springer, 2001
Unicast protocols send a separate copy of the media stream from the server to each recipient. Unicast is the norm for most Internet connections, but does not scale well when many users want to view the same television program concurrently. Multicast protocols were developed to reduce the server/network loads resulting from duplicate data streams that occur when many recipients receive unicast content streams independently. These protocols send a single stream from the source to a group of recipients. Depending on the network infrastructure and type, multicast transmission may or may not be feasible. One potential disadvantage of multicasting is the loss of video on demand functionality. Continuous streaming of radio or television material usually precludes the recipient's ability to control playback. However, this problem can be mitigated by elements such as caching servers, digital , and buffered media players.
IP Multicast provides a means to send a single media stream to a group of recipients on a computer network. A multicast protocol, usually Internet Group Management Protocol, is used to manage delivery of multicast streams to the groups of recipients on a LAN. One of the challenges in deploying IP multicast is that routers and firewalls between LANs must allow the passage of packets destined to multicast groups. If the organization that is serving the content has control over the network between server and recipients (i.e., educational, government, and corporate ), then routing protocols such as Protocol Independent Multicast can be used to deliver stream content to multiple Local Area Network segments. As in mass delivery of content, multicast protocols need much less energy and other resources, widespread introduction of reliable multicast (broadcast-like) protocols and their preferential use, wherever possible, is a significant ecological and economic challenge. Peer-to-peer (P2P) protocols arrange for prerecorded streams to be sent between computers. This prevents the server and its network connections from becoming a bottleneck. However, it raises technical, performance, security, quality, and business issues.