VIM defines messaging as a stored-and-forward method of application-to-application all program-to-program data exchange. The objects transported by a messaging system are called messages. The message, along with the address is sent to the messaging system. The messaging system providing VIM services accept the responsibility for outing and delivering the message to the message container of the recipient.
VIM interface is designed to facility messaging between VIM-enabled electronic mail systems as well as other applications. The VIM interface makes mail and message services available through a well defined Interface. A messaging service enables its clients to communicate with each other in a store and forward manner. VIM-aware applications may also use one or more address books. Address books are used to store information about users, groups, applications and so on. Address books are use to store information about users, groups, applications, so on.
When an object is linked, the source data object, called the link source, continues to stay whenever it was at the time the link was created. This may be at the object server where it was created, or where it has been copied. Only reference is required in the hypermedia document. The reference is also known as link. This link reference includes information about the multimedia object storage, its presentation parameters, and the server application that is needed to display/play or edit it. When this document is copied, the link reference is transferred. But the actual multimedia document remains in its original location. A linked object is not a part of the hypermedia document and it does not take up storage space within the hypermedia document. If the creator, or authorized user edits the original stored multimedia object, subsequent calls to the linked object bring the copy.
OLE will create significant support problems for uses if there is incomplete link tracking between documents that have been mailed between PCs and the application which created those objects. Use should have strong link tracking across distributed desktop and note book computers. During distributing, we should ensure that all users have same applications, or that the set of applications being used have registered their object conversion capabilities with OLE
Indeo is a digital video recording format. It is a software technology that reduces the size of uncompressed video files though successive compression methodologies, including YUV sub sampling, vector quantization, Huffman’s run length encoding, and variable content encoding.
Indeo technology is designed to be scalable for playing back video; it determines the hardware available and optimizes playback for the hardware by controlling the frame rate. The compressed file must be decompressed for playback. The INDEO technology decompresses the video file dynamically in real time for playback. Numbers of operating systems provide Indeo technology as standard feature and with other software products.
An Apple QuickTime product is also an integrated system for playing back video files. The QuickTime product supports for compression methodologies.
In Apple’s QuickTime a hypermedia report is more complex. It requires the following steps:
1. Planning.
2. Creating each component.
3. Integrating Components.
We should determine which components are required for the message, in what sequence should they be, and where in the text report they should be referenced. The length of each component should be determined. Careful planning is necessary to ensure that the capabilities of the messaging system are used appropriately.
It is the most common environment for multimedia messaging. VFW providing capture, edit, and playback tools for full-motion video
The tools provided by VFW are:
* The VidCap tool, designed for fast digital video capture.
* The VidEdit tool designed for decompression, edition and compressing full motion digital video.
The VFW architecture uses OLE. With the development of DDE and OLE, Microsoft introduced in windows the capability to link or embed multimedia objects in a standardized manner. Hence variety of windows based applications can interact with them. We can add full-motion video to any window-based application with the help of VFW. The VFW playback tool is designed to use a number of codec’s (software encoder/decoders) for decompressing and playing video files. The default is for AVI files.
The playback system allows the recipient to detach the embedded video reference object, interpret its content and retrieve the actual video clip from a specialized video server and launch the playback application.
A number of factors are involved in playing back the video correctly.
They are:
1. How the compression format used for the storage of the video clip relates to the available hardware and software facilities for decompression.
2. Resolution of the screen and the system facilities available for managing display windows. The display resolution may be higher or lower than the resolution of the source of the video clip.
3. The CPU processing power and the expected level of degradation as well as managing the degraded output on the fly.
4. Ability to determine hardware and software facilities of the recipients system, and adjusting playback, parameters to provide the best resolution and performance on playback.
The three main technologies for playing full motion video are Microsoft’s video for Window’s, Apple’s quick time and Intel’s Indeo.
An authoring system is an important component of a multimedia messaging system. A good authoring system must provide a number of tools for the creation and editing of multimedia objects. The subset of tools that are necessary are listed below:
1. A video capture program - to allow fast and simple capture of digital video from analog sources such as video camera or a video tape.
2. Compression and decompression Interfaces - for compressing the captured video as it is being captured.
3. A video editor with the ability to decompress, combine, edit, and compress digital video clips.
4. Video indexing and annotating software for marking sections of a video clip and recording annotations.
5. Identifying and indexing video clips for storage.
