home audio video interoperability-HAVI- full report
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Eight major consumer electronics manufacturers have come up with an open standard enabling home entertainment devices to communicate intelligently with each other. The HAVi (Home Audio Video Interoperability) standard promises to bring true platform independent interoperability to consumer devices using high bandwidth IEEE 1394 (FireWire) as the connecting medium. This paper studies the HAVi standard and what it has to offer to consumers.
An average household nowadays contains many very complicated devices. Many of them are home entertainment devices related to handling different audio or video data. These devices are computers in essence, but just more specialized in their features than a home PC. Home networking has become very popular nowadays since a normal household might contain several PCs that need to use shared resources like printers or file shares. Home audio and video devices like VCR, TV, amplifier, tuner, DVD, CD player and set-top-box form a similar interconnected network (see Figure 1). Why couldnâ„¢t these miniature computers also make use of each otherâ„¢s features and even control each other to make everything easier for the consumer
Major consumer electronics, software, semiconductor and computer manufacturers think that this should be possible and have decided to make it happen. The manufactures, namely Grundig, Hitachi, Panasonic, Philips, Sharp, Sony, Thomson and Toshiba along with now over 230 other participants, have formed a non-profit organization called HAVi (Home Audio Video Interoperability) for promoting the development of interoperable consumer products. The goal of HAVi organization is to provide a standard open architecture for intelligent audio and video devices to interoperate with each other
Regardless of manufacturer, operating system, CPU or programming language used for implementation (HAVi, Inc., 2001a).
The first beta version of the HAVi standard version 1.0 was published in December 1998while the final 1.0 version was released in December 1999. The current version of the specification is 1.1 (HAVi, Inc., 2001b) and it was published in May 15th 2001.This paper presents the basic architecture and promises the HAVi standard offers. Various problems and questions still to be answered will also be discussed. Although HAVi is still to come into living rooms as a de facto standard, a brief look at the future of HAVi will be made. The paper is mainly based on the information offered by HAVi organization (HAVi, Inc., 2001a) and naturally the HAVi specification version 1.1 itself (HAVi, Inc., 2001b). Another main source of the paper is a HAVi introduction by Rodger Lea, Simon Gibbs, Alec Dara-Abrams and Edward Eytchison (Lea et al., 2000
2 PROMISES OF HAVI
The idea of an open standard sounds very promising, but how can a normal consumer benefit from it How can it make lives easier and what kind of things, not possible before, can be achieved by using it
The simplest example might be time synchronization between different devices. TV set might get the correct time from the broadcast stream and the other devices can query the TV and set their own clocks according to it. Setting the VCR to record a program is a familiar situation users usually have problems with. With HAVi enabled devices this task can be made very easy. User can select the program (s)he wishes to record with the Electronic Program Guide(EPG) residing on a digital TV set (or set-top-box). The task can be as simple as just browsing the program information, selecting the desired program and pressing one button to activate recording. The TV then locates an available recorder (e.g., a VCR or a recording DVD device) and commands it to record the program supplying it with the time, length and channel parameters taken from the EPG. Thus, the user doesnâ„¢t need to program or touch the recording device in any way.One of the more advanced scenarios might be automatic directing of an oncoming videophone call to the TV screen or part of it and muting all other sounds. Similarly, if a camera placed outside the door detects movement, the picture is automatically connected to the TV screen notifying the user about a possible visitor. All this could also be aided by giving voice commands to the devices. These are only some of the possible use cases. A lot more can be possible, especially when the HAVi devices are connected to other home appliances, PCs or even Internet. The possibilities HAVi offers seem endless and many of them might sound like science fiction or at least not likely in the near future, but that might not be the case. Many products have already been announced and several working demos have been presented at various consumer electronics fairs. HAVi (Home Audio Video interoperability) provides a home networking standard for seamless interoperability between digital audio and video consumer devices. In other words, all audio and video appliances within the network will interact with each other and allow functions on one or more appliances to be controlled from another appliance, regardless of the network configuration and appliance manufacturer. The spirit of HAVi is to extend the capabilities of consumer audio and video systems while decreasing the complexities
of their operation. It is expected that HAVi will become the de facto standard for high quality A/V networks HAVi will provide for a home network, which is optimized for audio and video devices .The main reason for having a dedicated HAVi network for the audio and video devices is that for the exchange of high quality digital video and high fidelity audio signals, a much higher bandwidth is necessary than can be provided by other home networks that are optimized e.g. to control home devices such as lighting, heating, air-conditioning, cooking appliances, etc. The possibility to integrate other home networks such as existing analog links, telephone lines or new wireless technologies into the HAVi network, was built into the HAVi architecture from the beginning and bridges to these networks are likely to be developed in the future.HAVi is an initiative from eight major Consumer Electronics companies. The eight CE companies are Grundig AG,Hitachi, Ltd., Matsushita Electrical Industrial Co., Ltd. (Panasonic), Royal Philips Electronics, Sharp Corp., Sony Corp., Thomson Multimedia and Toshiba Corp.HAVi provides an environment for audio and video devices to interoperate with each other, irrespective of the actual brands or their HAVi implementation. The HAVi architecture is open, scaleable in implementation complexity, platform-independent and language neutral, i.e. HAVi can be implemented in any programming language and on any CPU or real-time operating system. It provides CE manufacturers the freedom to develop interoperable devices while additionally, application developers can write Java applications for these devices using the open Interoperability API that HAVi provides.
Current CE devices, such as Digital STBs and DV camcorders, contain sophisticated digital processing and storage systems. Future devices will contain even more sophisticated resources. By connecting these devices into the HAVi network it is possible to share their resources and use these to build up more sophisticated applications, such as
having two VCRs connected to two tuners with either VCR able to record the signal from either tuner. Under the HAVi system there is no single master controlling device: any device in the HAVi network that has been designed to do so can control other devices. Both the controlling devices and the controlled devices can be located anywhere within the HAVi network. HAVi also allows a device to be a controlling device and a controlled device atthe same time. The benefit of a network of interoperable devices is that the whole is greater than the sum of all the components. For example, the time and program channels of a video recorder could be set by the information received by the television tuner. The user can now program a recording on a VCR following a menu generated by the TV on the TV screen. Even one step further, HAVi allows the TV to generate a complete menu structure to interact with any HAVi device or a combination of devices in the network, using ONLY the TVâ„¢s remote control, and present the system in a consistent way to the user. This will significantly improve the user-friendliness of the system. In the sameExample, if the VCR is also a controlling device, it could detect at recording time that the original tuner is not available e.g. because it is already in use by someone else. It could try to resolve this situation by trying to find another
2.1 HAVi and Home Networking
HAVi, Home Audio Video Interoperability The interoperability of HAVi devices seems pretty extensive and complex. Will the installation and configuration of the network be as complicated as in computer networks Fortunately no, since devices are hot-pluggable and they are supposed to automatically announce their presence and capabilities to other devices and configure themselves when connected to the network saving the user from reading installation instructions and configuring network addresses and drivers. Finally, HAVi standard promises to be future proof by maintaining current functionality while making it easy to upgrade and add new capabilities. Non-HAVi devices can also be connected to the network if at least one of the HAVi devices supports the interface the legacy device provides. Here are some examples of how a HAVi system might work:
Â¢ You are watching a show on television, and a phone call comes in. You have programmed the television set to automatically mute, so you can carry on the phone conversation without distraction. If you wish, you can carry on the conversation in video-phone mode, and use the television screen as the display.
Â¢ Someone rings the buzzer at your front door. You walk over to a wall-based video intercom unit that is playing the five o'clock television news. The screen is switched to a video camera located over the front door so you can see who is there. The audio switches from the television show to a two-way link with the front door.
Â¢ You are watching an educational television show, and a scientist uses a word that you do not recognize. You speak the word into a microphone, and an Internet-based dictionary, complete with speech recognition, looks the word up and displays the meaning(s) in the corner of the screen or announces the definition(s) in a synthesized voice.
The HAVi specification will be easy to upgrade. As is the case with popular Web browsers today, updates will be available for downloading from the Internet. You might even program the system to automatically download the updates as they become available. HAVi will be operational across devices from all participating manufacturers. Users will be able to choose their own favorite hardware brands. The video disk recorder (VDR), television set, telephone, home video intercom system, computer (if wanted), and telephone set (with or without video) might all be manufactured by different companies, but they will function seamlessly in the HAVi-based network. When a new device, such as a printer/scanner/fax machine, is installed, the system will configure itself to accommodate it. Somewhat similar standards for interconnecting devices include Home API (HAPI), Open Services Gateway Initiative (OSGi), Universal PlugnPlay, and Vesa Home Network. HAVi and Vesa are specifically aimed at the home entertainment environment. The other standards are aimed at remote interconnection and make use of Internet protocols
3 HAVI ARCHITECTURE
The HAVi architecture can be divided into several different layers (see Figure 2). On the
bottom there is always vendor specific hardware and software Application Programming
Interface (API) that HAVi is built upon. Also, on the hardware level there is the connecting IEEE 1394 wiring, which HAVi devices use as a connecting medium. Next, a media manager for IEEE 1394 is needed as well as a messaging system. On top of the messaging system, there are several software modules: Registry, Event Manager, Stream Manager, Resource Manager, Device Control Modules (DCM) and DCM managers. These layers compose the basic services for building portable distributed applications. Basic services provided by the system, include:
Â¢Automatic discovery or devices added or removed from the network
Â¢Addressing scheme and message-transfer service
Â¢Lookup service for discovering resources
Â¢Posting and receiving local or remote events
Â¢Automatic installation and configuration of DCMs
Â¢Streaming and controlling isochronous data streams
Â¢Reserving devices and performing scheduled actions
Â¢Device control via DCMs and FCMs
Â¢User interaction with UI mechanisms
3.1 HAVi Devices
HAVi devices are classified into four categories (see Table 1): Full AV devices (FAV),
Intermediate AV devices (IAV), Base AV devices (BAV) and Legacy AV devices (LAV).
HAVi compliant devices fall into the first 3 categories and all other devices belong to the 4th category. FAVs and IAVs are controlling devices in the HAVi network while BAVs and LAVs are the devices they control.
Table 1: Device classes and software elements required for the four HAVi device
classes. The use of parentheses indicates optional component
Software element FAV IAV BAV LAV
DDI Controller (x) (x)
Resource Manager x (x)
Stream Manager x (x)
DCM Manager x (x)
Registry x x
Event Manager x x
Messaging System x x
Communications Media Manager x x
Device Control Module x (x) x x
IEEE 1394 x x x (x)
IEEE 1212r x x x (x)
IEC 61883.1 FCP x x (x) (x)
IEC 61883.1 CMP x (x) (x) (x)
A Full AV device has the most complete set of HAVi features. FAV contains a runtime
environment for Java byte code allowing it to upload byte code from other devices. This feature provides much enhanced capabilities for controlling devices. Common FAV devices might be set-top-boxes, digital TV receivers, general-purpose home-control devices, residential gateways or even PCs.
IAVs are generally a bit cheaper and do not contain the Java environment, thus having more limited capabilities for controlling other devices. IAVs may provide native support for controlling particular devices on the home network. Home theater amplifiers or DVD players might fall into this category.
BAVs do not contain any of the HAVi software modules. However, their configuration Rom must contain up loadable Java byte code that makes it possible for FAV devices to control them. They can also be controlled by an IAV device using native code. Most likely BAV devices include portable audio players, camcorders and mass storage systems.LAV devices do not recognize HAVi architecture. They use proprietary control Protocols.LAV devices can be divided into two categories, IEEE 1394 devices and those not supporting it. They can be connected to the HAVi network, but they need a FAV or IAV device acting as a gateway for them.
3.2 IEEE 1394
To meet the requirements for real-time transfer of high-data-rate streams, self-management and auto configuration, low-cost cabling and interfaces, a natural choice was to adopt the IEEE 1394 (FireWire) standard (IEEE, 1996) first conceived by Apple
Computer. IEEE 1394 meets all these requirements. Its high data rate of 400 Mbps (upgradeable to 800 Mbps or even 1600 Mbps) is quite enough for several simultaneous data streams. Data can also be fullduplex, i.e., both data and control instructions can flow to both directions at the same time. Scalability of up to 63 devices in the same bus should be quite enough for normal consumer electronics. FireWire can also connect almost any kind of computer peripherals such as printers, scanners, keyboards, displays and hard drivers. However, so far it isnâ„¢t very popular in normal PC environment except connecting workstations with digital video cameras for video editing. Naturally Apple products utilize it more commonly since it is a built-in feature in their workstations.
On top of the IEEE 1394 layer, HAVi uses a simple Function Control Protocol (FCP) defined in IEC 61883.1 (IEC, 1998,) for the transport of command requests and responses. IEC 61883.1 also specifies a Connection Management Protocol (CMP) for creating, breaking, overlaying and restoring isochronous connections and for Common Isochronous Packet (CIP) format.
3.3 Software Modules
HAVi software elements are self-contained entities that communicate with each other in peer to-peer fashion. Each software element has a well-defined API through which the services can be accessed. Elements also have a unique identifier assigned by the messaging System before they register to the Registry. Since this unique identifier is used to pass messages between different modules, there is no distinction whether the modules reside within the same device or different devices on the same network. In addition to assigning unique ID to the software elements, the messaging system fragments the messages into multiple FCP packets and reassembles them. Software elements can request the messaging system to supervise other elements and notify if they become unavailable. The HAVi messaging system supports both acknowledged and unacknowledged messaging.
Registry acts as the directory service of the network. It enables objects to locate other objects on the same network. In addition to the unique identifiers, the registry contains a
Small set of software element attributes. Clients can then, e.g., query the attributes of a specified element or locate an element matching a search predicate. Registry also forwards the queries to all remote registries and returns the replies to the client.
Device Control Modules allow the controlling device to control other devices. A DCM might contain several function specific Functional Component Modules (FCM). HAVi 1.1 defines the following FCMs: tuner, VCR, clock, camera, AV disc, amplifier, display, AV display, modem and web proxy. DCM of a controlled device can be embedded in the controller or dynamically added by, e.g., uploading. HAVi also provides standard DCMs for controlling various kinds of devices, but proprietary DCMs can add vendor specific features and enhanced capabilities. DCM Manager is needed to make sure that each target device has only one DCM on the network. The hosting device is chose by a voting process. Device candidates can affect the voting process by setting preferences. Some device might be better suited to control the device than other candidates.
In some cases it is useful for objects to notify any changes its state to other objects. Event
manager monitors these events and posts a message to local software elements that have
subscribed to that event. It can also forward the events to other event managers for global
Stream manager is responsible for managing transfer of real-time streams on the network. The transfer can happen internally or between different devices. Applications create the streams by defining a source and destination and then invoking the local stream manager. Stream manager verifies that the source and destination type are compatible and then allocates the needed resources.
Resource manager is used to reserve and release FCMs and arrange scheduled actions.
Managing is needed to prevent conflicts between devices. Only one device should command a controlled device at any time. However, this only applies to commands that require, e.g., a change in the state of the device, but not commands that only get or view information.
3.4 User Interfaces
HAVi devices can be controlled through other HAVi devices on the same network. Thus, the user interface also needs to be portable. Device manufacturers can define graphical user interfaces (GUI) that can be rendered on a device with display capability. There are two ways to achieve this Level 1 UI and Level 2 UI.Level 1 UI is called Data Driven Interaction (DDI). DDI user interface elements (buttons, panels, etc.) are typically obtained from DCMs. DDI controller then connects to the controlled device and sends user action messages to it. The target notifies the state changes to the DDI controller. DDI controller just provides a way to remotely command a device; it doesnâ„¢t have any intelligence about actions and their consequences. Target device can suggest a preferred layout of the user interface, but the DDI controller might modify it depending on the display capabilities. If more than one DDI controller is connected to the target, all the views are synchronized by the target. Level 2 UIs are constructed with Java and support more advanced features based on a subset of Java AWT 1.1. HAVi also defines some extensions, such as support for different screen sizes and aspect ratios, alpha blending and video/image layering, support for remote control input and support for UI components patterned after Level 1 DDI elements.
All devices can send messages and events to each other without any restrictions. To avoid
some of the problems that may arise, HAVi specifies what type of messages and events each software element is allowed to send. Receiving system component will then check if the sender is allowed to send this message or event. For example, some system components might only accept messages from other system components. Protection from hostile or flawed applications is left to the device manufacturer.
HAVi protection scheme has only two levels, trusted and untrusted. Vendors shouldThoroughly test all system and other software elements before granting them trusted level. All dynamically installed software, like updates and software patches, should be verified to make sure they are valid and come from verified sources. This verification is done by digital signature algorithm specified in the HAVi standard
3.6 What you should know about HAVi
Everyone knows that the most frequently used electronic devices in the home are home entertainment products. Wouldn't it be exciting if they could all be operated from anywhere in the home, using whichever appliance is nearest to you
With the arrival of broadband communications infrastructure and the digitization of audio and video appliances, the time has come for a system that will give you simple control over complex technology. HAVi is a digital AV networking initiative that provides a home networking software specification for seamless interoperability among home entertainment products. Equally important, the HAVi specification is AV-device-centric, so it has been designed to meet the particular demands of digital audio and video. It defines an operating-system-neutral middleware that manages multi-directional AV streams, event schedules, and registries, while providing APIs for the creation of a new generation of software applications. Whatever their brand, the focus is on the control and content of digital AV streams. HAVi software takes advantage of the powerful resources of chips built into modern audio and video appliances to give you the management function of a dedicated audio-video networking system.
IEEE 1394 (i.LINKÃ‚Â® or FireWireÃ‚Â®) has been chosen as the interconnection medium. And it's a good choice. 1394 has more than enough capacity to simultaneously carry multiple digital audio and video streams around the house, and provides support for digital copy protection. Leading suppliers of consumer electronics are already committed to producing HAVi compliant products. And needless to say, the rest of the world won't be willing to wait. HAVi is quite simply the answer to the future of home networking. HAVi give you instantly coordinated function without becoming a system administrator! Each appliance added to the network automatically installs its own application and interface software. The complexity and sophistication has been built into the products and its power is harnessed to work behind the scenes, so that control is simple for the user. Moreover, as each appliance is added to the HAVi networking system, it's automatically registered by the system so that other devices know what it is capable of. Applications may possess several functions, no problem: this is possible across brands because HAVi has standardized the Application Programming Interfaces of the most common AV functions. This means that a VCR can search for an appliance that offers a clock with the time-of-day and automatically set its own timers. And more good news: HAVi's upgradeable nature means that you'll be able to increase the functionality of devices as updates become available. Not even a home PC is required for a HAVi network to operate. HAVi is the only standard today capable of fully exploiting AV capability today and into the future.
4. Four good reasons why you need HAVi now:
Functions on a device within the HAVi networking system may be controlled from another device within the system. Search for an available VCR to record a TV program, with commands being given via the menu selection of another TV display.
Â¢ Brand independence
Entertainment products from different manufacturers will communicate with each other when connected into a HAVi network. Imagine a variety of VCR's, hi-fis, DVD players, Minidisk machines, active loudspeakers, set-top boxes all daisy-chained together and showing up on the TV for you to control from your one remote commander!
HAVi compliant devices automatically announce their presence and capabilities
to every other device on the HAVi network, greatly simplifying installation and setup. Just plug-and-enjoy. No more complicated a drivers d difficult installation instructions. No configuration of network addresses or device
Â¢ Linked to the Past, Upgradeable in the future:
Today's i.LINK enabled camcorders and other devices will be able to be controlled on a HAVi network for basic functions. And most HAVi compliant devices will come with their own dynamic Device Control Modules. Updating functionality can be done by downloading/uploading new capabilities via the Internet. Also, additional or replacement products can simply be incorporated into the network.
Â¢ Havi builds your bridge to the future:
As consumers incrementally build entertainment networks from a basic cluster to a home-wide network, exciting new applications will emerge to offer additional flexibility, control and personalization to home entertainment. HAVi will make it easier for companies to build and market new application programs by using HAVi's API's or programming in Java. Bridges will also be available to home control systems, security systems, communication systems and PC based applications.
HAVi is clearly the only standard today that fulfills the whole promise of home entertainment networking; beyond even our wildest dreams. It's hard to predict how HAVi may affect our lives. The only limit, it seems, is the sky and our own imagination.
5. PROBLEMS WITH HAVI
HAVi as a technology hasnâ„¢t been widely tested and utilized in real environments. Naturally, until it is proven that everything works as it is supposed to, there are several problems to be foreseen.
One of the most important goals is platform-independent interoperability. However, it has
been seen that FireWire still isnâ„¢t as solid as you would think considering that it has been on the market for several years. In fact, FireWire alone has proven to be very complicated to implement. The only guarantee is that devices of the same brand and same and same kind of proprietary programming will most likely work together. Until all the major problems with FireWire have been solved, they will hinder HAVi.
Also, distributing audio and video data is still quite difficult since thereâ„¢s no one format that all devices understand. For example the data formats of a VCR, minidisk, CD player and MP3 player are quite different.
One important issue when dealing with home entertainment is digital rights management.
Without any copyright info data might be transferred freely between devices or even outside the home network. While it is legal to copy material for your self, the situation becomes more complicated when the HAVi network is connected to, for example, the Internet.
Big entertainment corporations will not like the fact that their material could be freely
distributed. This raises the question about how the devices are protected from intrusions from outside. HAVi specification leaves this issue mostly to the device manufacturers. It certainly wouldnâ„¢t be nice if someone could disable your home network from outside, thus rendering video cameras, set to watch your apartment, useless.
In another scenario, an intruder might get access to your personal home videos. These
scenarios might seem far-fetched, but more common situations might cause problems too. The network must withstand an attack from within too. Faulty device might act in a wrong way sending invalid messages or monopolizing the network with traffic. Also,
since devices can obtain byte code from another devices or even Internet, it should be made sure that faulty program code wonâ„¢t cause too much problems. Again, it can be visualized that one device gets an update containing a virus which it then uploads to every other device.
Due to the growing complexity of the devices and various standards, the initial models will most likely be priced quite highly for some time. A set-top-box implementing both HAVi and Multimedia Home Platform (MHP) will probably start with the price of a full-featured multimedia PC, which is too much for the majority of consumers. As long as these high-priced devices suffer from incompatibilities, they arenâ„¢t too tempting. Users will not like to have their expensive digital TV displaying error messages or crash once in a while. The high complexity of the protocols makes the verification of products very difficult and even the smallest mistakes in mass production of consumer electronics can cost quite a lot, both financially and in credibility.
Engineers have nice visions about how devices can be connected with each other and the
Internet, but the reason to do this just shouldnâ„¢t be Ëœbecause we canâ„¢. Sure, a lot of things not possible before can be realized with HAVi. HAVi promises easiness of use, which is
Welcomed since even setting the VCR to record can be a very formidable task sometimes.
However, so far the discussion and development has been quite technology driven and issues, such as usability and what consumers actually want, havenâ„¢t been discussed enough. Hopefully this situation will change when the technology is ready and devices become more common. Finally, Microsoft also has its position in the development of home networks and has introduced a competing standard, Universal Plug and Play (UPnP). UPnP is more tilted towards linking PCs with all kinds of home appliances together. HAVi and UPnP complete each other in many ways, but clashes between the two efforts might make situation a bit more complicated and slow down the development of devices.
6. THE FUTURE OF HAVI
HAVi technology was first demonstrated at Winter CES (Jan 2001) in Las Vegas. After that, many of the participating companies have announced HAVi enabled products during the last year. However, most of the products are not publicly available yet. Naturally, the first HAVi compatible devices are targeted towards high-end markets, i.e., to professionals and home theater enthusiasts. It is most likely that the situation wonâ„¢t change much with next 2-3 years at least, not until HAVi technology is more mature and cheaper to implement. To battle the high cost of the products and time to develop them, T. Nakajima (Nakajima etal. 2001) presents a cost effective way of developing HAVi appliances. This solution uses Linux as the operating system and Java as the programming language. Transferring the system and applications to the product is easy since the development platform and the final product can both use Java and Linux. Linux was a natural choice, because it has recently gained popularity in embedded systems. Since virtually no modifications are needed, the development time and cost should be greatly reduced. However, Linux still has some problems to be solved, such as real-time resource management and making the memory footprint small enough.
Another development area is connecting HAVi to other networks, namely the Internet. This allows appliances to be remotely commanded with any device with a browser connected to the Internet. For example, it could be possible to use a PDA to remotely program the VCR.
R.G. Wendorf and M.P. Boedlander (2000) have demonstrated this in their paper. In this
solution, a Messaging System Proxy encodes HAVi messages into Extensible Markup
Language (XML) and SOAP. The encoded messages are then sent to Internet using
Hypertext Transfer Protocol (HTTP). Vice versa, incoming messages are stripped from XML and SOAP and put on the HAVi network. All this functionality can be achieved without modifying the HAVi specification itself or adding features to Internet connected devices.
7.1 FAQ: Device Types
1. What are the various types of HAVi devices
HAVi classifies Consumer Entertainment (CE) devices into four categories: Full AV (FAV), Intermediate AV (IAV), Base AV (BAV), and Legacy AV (LAV). HAVi-compliant devices are those in the first three categories, all other CE devices fall into the fourth category. Referring to the distinction between controllers and controlled devices -- FAVs and IAVs are controllers while BAVs and LAVs are controlled devices.
FAV -- FAV is an acronym for Full Audio Visual device. An FAV contains a complete set of the software elements comprising the HAVi Architecture. This device class generally has a rich set of resources and is capable of supporting a complex software environment. The primary distinguishing feature of an FAV is the presence of a runtime environment for Java byte code. This allows an FAV to upload byte code from other devices and so provide enhanced capabilities for their control. Likely candidates for FAV devices are Set-top Boxes, DTV receivers, general purpose home control devices, residential gateways, and home PCs.
IAV -- IAV is an acronym for Intermediate Audio Visual device. An IAV is generally lower in cost than an FAV and more limited in resources. IAVs do not provide a runtime environment for Java byte code and so cannot act as controllers for arbitrary devices within the home network. However, an IAV may provide native support for control of particular devices on the home network.
BAV -- BAV is an acronym for Base Audio Visual devices .These are devices that, for business or resource reasons, choose to implement future-proof behavior by providing up loadable Java byte code, but do not host any of the software elements of the HAVi Architecture. These devices can be controlled by an FAV via the up loadable byte code or from an IAV via native code. The protocol between the BAV and its controller may be proprietary or a standard device control protocol such as AV/C.
LAV -- LAV is an acronym for Legacy Audio Visual devices. These are devices that are not aware of the HAVi Architecture. LAVs generally use proprietary protocols that provide control-only functionality. Such devices can work in the home network but require that FAVs or IAVs act as an intermediary.
2. What are the benefits of FAVs to users
Because FAVs have the ability to install Java applications on them, FAVs offer the following benefits:
1. Forward Compatibility ("Future-proofing"). The ability of a device, or a system of devices, to gain additional functionality or features by installing new or upgraded software (such as Java applications) onto it. This means that devices do not become obsolete as new devices come onto the market - they can be upgraded with new features.
2. Platform independence. Because Java is platform independent and the APIs are standardized by HAVi, Java applications will run on any FAV, regardless of manufacturer.
3. Programmers support. Java is supported by a large community of developers and is being adopted by a growing number of standards bodies like DVB and ATSC. This will provide for a large base of potential application developers for HAVi.
4. Link with the Internet and broadcast systems. Java is the key language for Internet-based applications. Standards bodies like DVB, ATSC and DAVIC are defining Java APIs to enable interactive applications to be downloaded to devices such as set-top boxes. When a Java API, as defined by HAVi, is implemented on a device, such a set-top box or an internet-enabled TV, these devices can interact with all the HAVi devices in the home.
3. Is a single IAV or FAV device capable of controlling multiple devices
Yes, one IAV or FAV device can control multiple devices via multiple DCMs (for each target device).
4. Can any combination of IAVs and FAVs operate and interact in a HAVi network
Yes. All the mechanisms in HAVi are designed to achieve interoperability that is equally supported by all FAVs and IAVs. IAVs and FAVs cooperate in a peer-to-peer fashion and there is no need for a special master device.
5. Are there specific types of devices that need to be designed as IAV or FAV devices
No. Whether a HAVi device is built as an IAV or FAV is the choice of the manufacturer. However, on devices that already support Java (such as set-top boxes), it would be reasonable to expect this type of device to be designed as an FAV
7.2. FAQ: General Information
1. Is HAVi just a standard or a full object code for several platforms
HAVi puts forward a set of platform-independent APIs (in the form of HAVi specification document) that allow licensed developers to easily develop home-networking applications. HAVi does not put forward a standard object code; the implementation of the HAVi software stack is left to each company, with the condition that the implementation must be fully compatible with the HAVi specification (see Compliance section).
2. What does "HAVi compliance" mean
A "HAVi compliant" device will:
Â¢ Support IEEE-1394
Â¢ Provide HAVi SDD data in IEEE 1212 configuration ROM
Â¢ Support IEC 61883
Â¢ Conform to the standards of the HAVi Compliance Test Specification
3. What must device makers and third-party software vendors do to produce HAVi-compliant devices and applications
Device makers must:
Â¢ Ensure that their devices are IEEE-1394 compatible.
Â¢ Incorporate HAVi SDD data (such as device class) inside the configuration ROM.
Â¢ Make DCM/FCMs (and optionally, GUI), for operating the devices available.
Â¢ Incorporate the HAVi device class software elements.
Third-party software vendors should:
Â¢ Ensure that the DCM/FCM and applications they write using the HAVi API's satisfy all the requirements specified in the Compliance Test Suite documents.
4. What are the advantages of HAVi-enabled devices
The HAVi specification offers advantages for both the end user and the device manufacturer.
Some advantages for Developers:
Â¢ Develop home-networking applications easily by using the platform-independent HAVi native API or Java-binding HAVi API.
Â¢ Create new digital AV products covering a wide cost/functionality spectrum based on HAVi scalability.
Â¢ Exploit the advantages of IEEE-1394, such as plug-and-play and fast data transfer.
Â¢ Explore new business opportunities writing compatible applications for devices from other manufacturers.
The HAVi Specification was developed for home entertainment AV networks, providing high bandwidth for transmitting multiple AV streams and featuring easy "plug-and-enjoy". The HAVi specification allows for automatically detecting devices on the network, coordinating the functions of various devices, installing applications and user interface software on each device, and ensuring interoperability among devices regardless of manufacturer.
5. Who will write HAVi applications How can these be updated
HAVi applications can be written by device manufacturers, third-party software developers, and service providers.
These applications can be updated in two ways:
Â¢ The standard method in HAVi is to have the application downloadable from a URL or cable service provider, and run on the Java virtual machine (JVM) inside an FAV device.
Â¢ Non-standard (i.e. proprietary) methods in which the application could be introduced into the HAVi device would be via PCMCIA Flash-ROM card, MO disk, floppy-disk, etc.
6. Who will develop DCM/FCMs
Since developing the DCM/FCM requires knowledge of the underlying hardware and software of the device, it would logically be developed by the device makers themselves, or third-party software vendors who have licensing agreements from the device maker.
7. What FCM APIs are defined in the HAVi specification
The following FCM APIs have been defined in the HAVi specification:
8. Can a developer define an FCM if current standardized FCMs (VCR, Tuner, Webproxy, etc.) do not meet their needs
Yes, developers can define their own FCM APIs. However, these new FCM API's must be made available for other developers, by licensing them to application developers, or making them publicly open.
Developers can also join the HAVi organization and propose these API's for inclusion in the HAVi specification.
9. Is there an FCM Manager similar to DCM Manager
No, there is no FCM Manager, because the DCM Manager installs the DCM, and the DCM itself installs the FCMs.
10. Does HAVi specify standards for DCMs on LAV devices
Standardization of the DCM for LAV devices falls outside the scope of HAVi, and so it is left to the device manufacturer to provide proprietary DCMs.
11. Will HAVi API be modified in future versions As the HAVi API's are improved/updated, will the older API's and applications become incompatible with newer versions
As the official release of the specification evolves, it is intended that no APIs will ever be updated or removed. All changes will be achieved by adding new APIs. This ensures that older components can always request services from newer components successfully. Therefore, the applications will remain compatible.
12. What is the schedule for HAVi and HAVi products
The finished HAVi v1.0 specification is now available. The licensing program has commenced and interested parties can apply for a license.
Each manufacturer or software developer will determine their own schedule for product development and market introduction.
13. Won't the overall hardware costs be very high, since a controller (with a fairly big display) would be required
Since HAVi provides the following flexibility to developers, device cost can be kept low:
Â¢ Developers can build cheaper controller devices in the form of IAV devices.
Â¢ The HAVi output device model allows developers to display text-based control panel.
Â¢ When graphics-based GUI's are to be displayed, very few fields are mandatory -- many fields are optional, allowing the costs to be kept down.
14. What are the changes between versions 0.8 and 1.0 beta, and versions 1.0 beta and 1.0
The main changes between versions 0.8 and 1.0 beta are as follows:
Â¢ Java bytecode has been selected as the standard format during uploading
Â¢ APIs for new FCMs have been added
Â¢ Security has been added
Â¢ Connectivity with external networks (e.g. Internet) has been incorporated
Â¢ APIs for GUI have been added. Between versions 1.0 beta and 1.0, there are almost no changes to the APIs themselves, only their operation has been thoroughly verified via plugfest.
15. What is the status of the HAVi plugfest
The initial "plugfest" regarding HAVi system software elements (such as CMM, Messaging System, etc.), various FCMs (Tuner FCM, VCR FCM, etc.) and Java-binding of HAVi APIs were completed in 1999 prior to the completion of the v1.0 specification.
The HAVi Organization may schedule additional technical sessions and "plugfest" opportunities for new members. The technical agenda of the HAVi Organization has not yet been published.
16. What is the status of compliance related documents
Compliance Test Suite document consisting of "Test Requirements" and "Test Cases" has been completed and is available for download.
17. What is the license policy/fee for HAVi development
Licensing for the HAVi specification is handled through Royal Philips Electronics on behalf of seven of the eight Promoter companies who co-created the HAVi Specification.
Â¢ One-time license fee of US $5,000.
Â¢ US $0.10 per product.
18. Are there any books regarding HAVi
Yes. A book titled "HAVi Example by Example" has been published. HAVi Example by Example introduces the programming interface packages and steps the reader through a wide range of examples. This book is intended for readers with an interest in Java programming or those intrigued by new home entertainment applications.
HAVi comes with great promises, promises that seem to be quite troublesome to fulfill.
However, with so many large companies working for a common goal, there is a good chance that HAVi will eventually prove to be what it promised. In the end, it is up to customers if they want to adopt the new technology. When new features and possibilities are as great as with HAVi, thereâ„¢s no question about the fact that HAVi will be something that customers want, provided that it comes with a reasonable price tag and solid functionality.
Bodlaender, M.P.; Wendorf, R.G., 2000, adding full internet protocol functionality to HAVi, Proceedings of the ICCE International Conference on Consumer Electronics 2001, pp.
IEEE, IEEE standard 1394, 1996, Standard for a High Performance Serial Bus,
Piscataway, N.J., IEEE Press, parts 1 - 5
IEC, IEC standard 61883, 1998, Consumer Audio/Video Equipment â€œ Digital Interface,
Geneva, Switzerland, Intâ„¢l Electro technical Commission,
HAVi, Inc., 2001a, The HAVi Homepage [online] <URL:http://havi.org> [referenced
HAVi, Inc., 2001b, The HAVi Specification Version 1.1, 529 p. Also available at
Lea, R.; Gibss, S.; Dara-Abrams, A.; Eytchison, E., 2000, Networking Home Entertainment
Devices with HAVi, Computer, Vol. 33 Issue 7, pp 171-178
2. Promises of HAVi
2.1 HAVi and Home Networking
3. HAVi Architecture
3.1 HAVi Devices
3.2 IEEE 1394
3.3 Software Modules
3.4 User Interfaces
3.6 What you should know about HAVi
4. Four good reasons why you need HAVi now
5. Problems with HAVi
6. The future of HAVi
7.1. FAQ: Device Types
7.2. FAQ: General Information
Active In SP
Joined: Sep 2010
18-10-2010, 02:59 PM
Eight major consumer electronics manufacturers have come up with an
open standard enabling home entertainment devices to communicate
intelligently with each other. The HAVi (Home Audio Video Interoperability)
standard promises to bring true platform independent interoperability to
consumer devices using high bandwidth IEEE 1394 (FireWire) as the
connecting medium. This paper studies the HAVi standard and what it has
to offer to consumers.
An average household nowadays contains many very complicated devices. Many of them are home entertainment devices related to handling different audio or video data. These devices are computers in essence, but just more specialized in their features than a home PC. Home networking has become very popular nowadays since a normal household might contain several PCs that need to use shared resources like printers or file shares. Home audio and video devices like VCR, TV, amplifier, tuner, DVD, CD player and set-top-box form a similar interconnected network (see Figure 1). Why couldn’t these miniature computers also make use of each other’s features and even control each other to make everything easier for the consumer?
Major consumer electronics, software, semiconductor and computer manufacturers think that this should be possible and have decided to make it happen. The manufactures, namely Grundig, Hitachi, Panasonic, Philips, Sharp, Sony, Thomson and Toshiba along with now over FireWire 2 30 other participants, have formed a non-profit organization called HAVi (Home Audio Video Interoperability) for promoting the development of interoperable consumer products. The goal of HAVi organization is to provide a standard open architecture for intelligent audio and video devices to interoperate with each other regardless of manufacturer, operating system, CPU or programming language used for implementation (HAVi, Inc., 2001a).
The first beta version of the HAVi standard version 1.0 was published in December 1998 while the final 1.0 version was released in December 1999. The current version of the specification is 1.1 (HAVi, Inc., 2001b) and it was published in May 15th 2001.
This paper presents the basic architecture and promises the HAVi standard offers. Various problems and questions still to be answered will also be discussed. Although HAVi is still tcome into living rooms as a de facto standard, a brief look at the future of HAVi will be made. The paper is mainly based on the information offered by HAVi organization (HAVi, Inc., 2001a) and naturally the HAVi specification version 1.1 itself (HAVi, Inc., 2001b). Another main source of the paper is a HAVi introduction by Rodger Lea, Simon Gibbs, Alec Dara- Abrams and Edward Eytchison (Lea et al., 2000).
for more details, please visit
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Joined: Mar 2010
21-12-2011, 12:42 PM
ppt presentation about home audio video interoperability you can find at
home vedio.pdf (Size: 1.28 MB / Downloads: 156)
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Joined: Feb 2012
18-02-2012, 11:38 AM
to get information about the topic havi home audio video interoperability full report ppt and related topic refer the link bellow
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