Wednesday, November 24, 2010

Multimedia components


Multimedia components

TEXT

Alphanumeric characters are used to present information in the text form. Computers are widely used for text processing.


Hardware Requirements for Text


Text processing, with the use of multimedia computers, generally involves the following hardware devices.1. Keyboards are most commonly used to input text data.2. OCRs (Optical Recognizers) are used for direct input of printed text to computers.3. Computer screens are used to display text information.4. Printers are most commonly used to output text in hard copy form.


Software Requirements for Text


The following text processing capabilities are highly desirable in a multimedia computer system for better presentation and use for textual information.
Text editing. Text editors and word processing packages are used to generate, edit and properly layout a text document.


Text style.


Presentation of text information can be made more effective by using text of various sizes, fonts and styles .For example ,newspapers use a good combination of all these styles to better highlights more important news than less important ones. Similarly ,in a book like the one you are now reading, a combination of various text styles are used to put more emphasis on certain words or phrases than the remaining text.


Text searching.


Usage of text information can be greatly enhanced by text searching features. This feature allows the users to enter a word or phrase, and the computer quickly finds and displays that part of the text where the world or phrase appears in the textual information, with the world or phrase highlighted.


Hypertext.


Both presentation and use of textual information can be greatly enhanced by using hypertext feature. This feature provides great flexibility of structuring and accessing computer based text information. It generalizes the concepts of “footnote” and “cross reference” of traditional anchor (a word or phrase linked to another document) within documents. An anchor is often called a “hotword”. This means, if the user wants more information about a particular hotword, he/she can select that hotword and open window with additional text explaining that word or phrase.


Text importing and exporting.


The task of creating a textual document can often be greatly simplified, if the document preparation software has text-importing feature. This is because some of the text you want to incorporate in your document may already exist as a file created by a word processor or a database file. The file can be simply imported into the new documents at the desired location, instead of retyping the entire text again. If the imported file is large, it will result in enormous saving of time and effort required to prepare the new documents. Similarly, text exporting feature is very useful in allowing other package to use an existing documents. For what is multimedia click here

What is a multimedia computer system?



What is a multimedia computer system?
A multimedia computer system is a computer system, which has the capability to integrate two or more types of media (text, graphics, images, audio, and video) for the purpose of generation, storage, representation, manipulation and access of multimedia information. In generate, the data size for multimedia information is much larger than textual information, because representation of graphics, animation, audio or video media in digital form requires much larger number of bits than that required for representation of plain text. Due to this, multimedia computer system requires:
Faster CPU (for quicker processing of larger amount of data).
Larger storage devices(for storing large data files),
Larger main memory(for running programs with large data size),
Good graphics terminal s(for displaying graphics, animation and video),and
Input/output devices required to play any audio associated with a multimedia application program.
All multimedia computer systems need not have all the features listed above. For example, a computer system, which does not have the capability to handle audio and video media can still be called a multimedia computer system, because it can still handle multiple media (text and graphics).However a full-fledged multimedia computer system must be capable of handling all types of media discussed above, and hence, must have all the features listed above.

Friday, November 19, 2010

What is MULTIMEDIA?


What is MULTIMEDIA?
A medium is something, which can be used for presentation of information .There are two basic ways to present some information.
1. Unimedium presentation. In this case, a single medium is used to present information. For example, a stereo system is a unimedium device, because it presents information by using only sound medium. Similarly, a book having only text is also a unimediaum device, because it presents information by using only text medium.
2. Multimedia presentation. In this case, more than one medium is used to present information. For example a TV system is a multimedia device, because it presents information by using sound and video media. Similarly, a book having both text and diagrams is also a multimedia device, because it presents information by using text, graphics and images.

Obviously, multimedia presentation of any information greatly enhances the comprehension capability of the user of the information because it involves the use of more of our sense. For example students in a class can understand a lecture better, if the lecturer draws illustrative diagrams on the board while delivering his/her lectures instead of using only voice explanation.
In case of computers system, the commonly used media for the purpose of storage, access and transmission of information are,

1. Text(alphanumeric characters)
2. Graphics(Line drawings and images)
3. Animation(Moving images)
4. Audio(sound)
5. Video(Videographer real –life events)

Hence in the computer world, multimedia refers to the use of more than one of the above listed media for information presentation to the computer users-such as text and sound.There are many problems to find that what is internet for more detail click here

What is Internet?


What is Internet?

The Internet is a huge network of computer, which links many different types of computers all over the world .It, is a network of network, which share a common mechanism for addressing computers, and a common set of communication protocols for communications between two computers on the network.

History

The Internet has its root in the ARPANET system the Advanced Rresearch Project Agency of the U.S.

Departments of Defense, ARPANET was the first WAN and had only four sites in 1986.The Internet evolved from the basic ideas of ARPANET for interconnecting computers, and was initially used by research organizations and universities to share and exchange information. In 1989, the U.S. Government lifted restrictions on the use of the Internet, and allowed it to be used for commercial purposes as well. Since then, the Internet has rapidly grown to become the world’s largest network. It now interconnects more than 30,000 networks, allowing more than 10 million computers, and more than 50 million computer users in more than 150 countries around the world to communicate with each other. The Internet continues to grow at a rapid pace.

Internet Basic Services

There are basically four types of services provided by the Internet to its users. These are given below.

1. Electronic Mail
2. File Transfer Protocol
3. Telnet
4. Usenet News

Wednesday, November 3, 2010

Usenet News Services

Usenet News

The Usenet service allows a group of Internet users to exchange their views/views/ideas/information on some command topic. Which is for interest to all the members belonging to the group? Several such groups exist on the Internet and are called newsgroups. For example, the newsgroup comp. Security .msc consists of users having interest in computer security issues.

A newsgroup is like a large notice board, which is accessible to all the members belonging to the group. A member, who wants to exchange his/her views/ideas information with other members, sends a specially formatted message, which is processed and interpreted as a notice to be posted on the notice board by the member’s computer, which has an appropriate software running for this purpose. After the processing of the message is cover. It can be read from any member’s computer just like a notice posted on a notice board can be read by anyone having access to the notice board.

There are two types of newsgroups-moderated and nonmoderated. In a moderated newsgroup, only selected members have the right to directly post a message to the virtual notice board, whereas in a no moderated newsgroup, any member can directly post a message to the virtual notice board. In a moderated newsgroup, a message sent by an ordinary member first goes to the computer of one of the selected members having the right to directly post a message to the notice board. The message is then checked by this member who decides whether the message is appropriate for being posted, and does any editing that might be required to improve the quality of the message. This member then posts the message on the notice board. After this only, the message becomes readable to other members.

The main idea of a moderated newsgroup is to ensure the quality of the newsgroup. As no one moderates the quality of the message of a no moderated newsgroup, anyone can post anything .However, member of such newsgroups should be careful in posting a message, because other members may react angrily by sending a flaming message in response to an ill mannered message. To address this assure, the concept of netiquette (network etiquette) has arisen, which deal with rules of framing message that will not hurt others.