Video on Demand is a dynamic feature offered by IPTV (Internet Protocol TV) . VoD is customer driven video service where video data is transmitted through Real-Time Streaming Protocol. It enables users to select and view video content of their choice from a list of available videos . It allows them to request immediate access to video content on PC’s or TV’s featuring videos from a wide selection including educational programs and remote learning facilities , weather forecast and local news, home shopping ,sports, games , films and music.
Generally television is on broadcast technology while VoD is provided as unicast transmission and is often used for videoconferencing. Internet Television , using the internet is an increasingly popular form of video on demand .
What is Video On Demand (VoD) ?
Video on Demand is a digital feature cable that allows to rent programs and movies from the comfort of your home with the functionality of pause , fast-forward and rewind just similar to a DVD player . Charges are applied to these videos via regular VoD menu .
VoD is a great way to eliminate the need to visit video stores to buy or rent movies , it was originally introduced in 1990 in Hong Kong and ever since became the part and parcel of most cable and network systems. A type of pay per view system, it has both streaming and downloadable video on demand systems . Streaming system allows viewers to watch as the video is being downloaded to a system while in downloadable a user can only start viewing after it is fully downloaded to a set top box .
VoD has all the functionality of a DVD, companies permit to watch a movie for a certain period of time so viewers can download it and watch whenever they choose on their digital video recorder (personal video recorder) or portable media player.
Viewers can not only watch films and television programs but also music, reality television and music. Some VoD providers as part of their package even offer free access to already shown programs .
At consumer level the interactive TV technology that allows real time subscription to videos comprises of a standard TV receiver with a STB (set top box) . The service can alternatively be delivered via internet to home computers , high-end cellular telephones sets and advanced digital media devices .
Previously VoD suffered from lack of available network bandwidth leading to bottlenecks and huge download pauses and delays . It works well over wide geographic region or on a satellite based network when there is a modest demand but when there is a pool of consumer demand for multiple programs then the data can overwhelm network resources . It can be mitigated by storing programs on geographically distributed servers and by providing programs on request to local users , this technology is called store and forward . It improves the overall reliability of system with use of single gigantic repository. With store and forward local providers can maintain their systems and billing structures independently .
Few airlines offers VoD facility to the passengers via video screens embedded in seats back or arm rests with portable media players offering specific stored audio and videos to play with fast forward, rewind and pause functionality .
Some forms of Video on demand includes SVOD i.e subscription on demand that has services such as Netflix which requires the user to pay a monthly fee to access a bundled set of content , another service being AVOD i.e advertising video on demand is free for users and this platform sells advertisements for generating its main revenue stream .
How Video On Demand Works ?
Video on Demand gives the system a realisation of a video rental shop brought into home . The key components of a VoD service includes a VIDEO SERVER that stores and provides program access , the Data Delivery NETWORK that interconnects the subscriber and STB (Set Top Box) which is an interface between home TV equipment and the VoD services.
Pre-recorded videos are digitally stored on video server and are then transmitted in compressed coded format , the videos then are decompressed and decoded by set top converters in individual homes as they are ordered via dual remote control or by interactive voice response. The picture quality matches to standard VHS .
Viewers can call on a lot of functions while watching videos , all this is processed by the set top box and are sent to the local server , the server then processes the request if feasible at that time otherwise relays it to a video archive server in much of a hierarchy system.
The compressed audios and videos are stored on hard disk and can be advertised on network, depending on available bandwidth multiple archive servers can simultaneously run over the network .
When a movie is requested by a subscriber from VoD , the end result is a compressed digital stream of bits which is transmitted from the video server to the STB which decodes it to the analog mode and finally displays it on TV directly or by modulating on RF channel which links both(tv to set top box).
The VoD steps can be quickly summarised as -
1. The digitized video is compressed and distributed to video server.
2. The video information is added to both management system and to the list of
movies from where the selection is made .
3. Allocating resources for delivery and setting up protection scheme to allow only
that particular subscriber to view the movie.
4. Lastly delivering the movie and to pay heed to user commands of pause ,stop,
forward or rewind.
Apart from sending video to the server there are other elements which has to be accountable for delivery of right video to the right person and a fair bill is generated for the services received. This process includes -
1. The billing system which is the repository of all financial transactions .
2. A Controller to direct the server about what action to take and to manage on-demand
services.
3. Another controller to allocate the resources to complete a request and to set path
ways from server to customer home channel .
4. A Management System to keep record of everything that transpires . It is connected
to all different elements and checks if billing system has enough credit to play a
requested movie and ask the network controller for desired bandwidth and to set the
path for optimum delivery .
It takes a while to verify the status of an account and once its done the services are launched, if customer is not entitled to service due to overdue bills or credit limits the services are stopped .
Video Server -
The main task of a Video Server is to deliver isochronous compressed video to correct port , the one connected to the downstream modulator and to address that video stream for customer STB to retrieve and recognize it . Even after delivering video it listens to commands from users . An ideal video server should be able to hold hundreds of terabytes of digital data and should be able to provide simultaneous access to hundreds of real time subscribers .
Set Top Box -
STB is a conflicted box which decodes analog channels and digital cable signals . It has a secured and sophisticated decryption hardware and a smart card that contains encrypted data providing access to only authorized customers.
STB’s have secured software that operates on all elements in real time and generates display , handles notifications and to maintain updated schedule informations . Being limited memory few applications have to be loaded on request via high speed path or from a separate channel.
We at Oodles Technologies have extensive experience in Video Transcoding and Video Content Delivery , our developers are skilled in developing Set Top Box applications using NETGEM and ROKU SDK’s .
To discuss how we can help you, please contact with our team at info@oodlestechnologies.com or skype : oodles.tech
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