How video streaming works?

Streaming is a technology used to deliver content to computers and mobile devices over the internet. Streaming transmits data – usually audio and video, but increasingly other kinds as well – as a continuous flow, which allows the recipients to begin to watch or listen almost immediately.

But, it wasn't until the late 1980s or early 1990s that computers had the hardware and software that was capable of playing audio and displaying video. The streaming video technology on the internet came a long way from popping up progress bars or buffering statuses on your screen.

Today, the video is everywhere. We all watch videos online - YouTube is the most popular video hosting platform for a reason! However, it’s not just about websites - it’s about the concept of live video streaming itself. With the availability of high-speed cellular networks and powerful phones, people are consuming video at an incredible pace, and all indications point to it continuing to grow. Speedier internet connections, enhanced decoders, and plugins, better-equipped computer machines, all contribute to putting the fun back to streaming video online. What is it, exactly, and how does it work? Let's take a closer look at it -

What is video streaming?

Streaming video is content sent in compressed form over the Internet and displayed by the viewer in real time. With streaming video or streaming media, a Web user does not have to wait to download a file to play it. Instead, the media is sent in a continuous stream of data and is played as it arrives. The user needs a player that uncompress and sends video data to the display and audio data to speakers. A player can be either an integral part of a browser or downloaded from the software maker's Website.

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. Live video on IP networks first by Starlight Networks for video streaming and Real Networks for audio streaming. Live streaming 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.

The way of the Streaming process

In a nutshell, there are three widely used ways to stream a video such as - Progressive Download, RTMP/RTSP Streaming, and Adaptive HTTP Streaming.

Progressive Download

Progressive Download is the most widely used video delivery method by far (in part because it’s what YouTube uses). It’s also easiest to implement: just put a video on your web server and point your player to the URL. Once a user hits play, the player immediately starts downloading the file. The player will start video playback as soon as it has enough data to do so, but it will continue to download until it has received the whole file (hence the progressive). Progressive Download is supported by Flash, HTML5 browsers, the iPad/iPhone and Android. On the server side, every regular web hosting supports downloads, as does every CDN (Content Delivery Network; web hosts that special in large-scale delivery). In most cases (Flash needs a small server module), it is possible to seek in a player to a not-yet-downloaded part of the video. At that point, the player re-downloads the video, starting at the seek offset instead of at the beginning. We call that feature pseudo-streaming.

Adaptive HTTP Streaming

Adaptive HTTP Streaming is a fairly new streaming format. It attempts to join the merits of RTMP/RTSP Streaming (bandwidth efficiency, quality switching) with those of Progressive Download (no special servers or protocol needed). Adaptive HTTP Streaming works by storing your videos on the server in small fragments (a few seconds each). The player then glues these fragments together into a continuous stream.

RTSP/RTMP Streaming

RTMP/RTSP Streaming is widely used by professional media organizations like Hulu. This method uses specialized web servers that only deliver the frames of a video the user is currently watching. No data is downloaded in advance and data a user has seen is immediately discarded. RTMP/RTSP Streaming works great even for long-form or live video. It has specific server and protocol requirements, which makes it less accessible and adds significant complexity and cost as compared to Progressive Download.

How does it work?

The success of streaming media is pretty recent, but the idea behind it has been around as long as people have. When someone talks to you, information travels toward you in the form of a sound wave. Your ears and brain decode this information, allowing you to understand it. This is also what happens when you watch TV or listen to the radio. Information travels to an electronic device in the form of a cable signal, a satellite signal or radio waves. The device decodes and displays the signal.

In streaming video and audio, the traveling information is a stream of data from a server. The decoder is a stand-alone player or a plugin that works as part of a Web browser. The server, information stream and decoder work together to let people watch live or prerecorded broadcasts.

Several things had to come together before streaming media could happen -

• Using your Web browser, you find a site that features streaming video or audio.

• You find the file you want to access, and you click the image, link or embedded player with your mouse.

• Then you selects a type of file to be watched on the computer, either .mov, .rm, .wmv, .flv or more.

• The Web server hosting the Web page requests the file from the streaming server.

• The software on the streaming server breaks the file into pieces and sends them to your computer using real-time protocols.

• The browser plugin, standalone player or Flash application on your computer decodes and displays the data as it arrives.

• Your computer discards the data.

• You own a player such as QuickTime, RealMedia, Adobe Flash or similar, and uses a web browser plugin, in order to successfully stream a video.

How do you upload a video or audio file?

• Creating and distributing a streaming video or audio file requires the following steps -

• You record a high-quality video or audio file using film or a digital recorder.

• You digitize this data by importing it to your computer and, if necessary, converting it with editing software.

• If you're creating a streaming video, you make the image size smaller and reduce the frame rate.

• A codec on your computer compresses the file and encodes it to the right format.

• You upload the file to a server

• The server streams the file to users' computers.