Computer Basics

3 -Input: Multimedia

Multimedia is a combination of sound and images with text and graphics. This would include movies, animations, music, people talking, sound effects like the roar of a crowd and smashing glass.

Sound Input

Recording sounds for your computer requires special equipment. Microphones can capture sounds from the air which is good for sound effects or voices. For music the best results come from using a musical instrument that is connected directly to the computer. Software can combine music recorded at different times. You could be a music group all by yourself -singing and playing all the parts!

Voice Input

Voice input systems are now becoming available at the local retail level. You must be careful to get the right system or you'll be very disappointed.

Decide first what you want to do since a voice input program may not do all of these:

Data entry -	Talking data into the computer when your hands and eyes are busy should certainly be more efficient. You'd have to be very careful about your pronunciation!
Command and control -	Telling the computer what to do instead of typing commands, like saying "Save file". Be careful here, too. The dictionary of understood words does not include some of the more "forceful" ones.
Speaker recognition -	Security measures can require you to speak a special phrase. The computer must recognize your voice to let you in.
Speech to text -	Translating spoken words direct to type would suit some authors just fine. You'd have to watch out for those "difficult to translate" phrases like "hmmm" and "ah, well, ... ummm."

A number of companies are now using speech recognition in their telephone systems. For example to find out what your bank account balance is, instead of punching in your account number on the phone keypad and choosing option 3 for current balance, you could speak your account number and say "Current balance". The computer will even talk back and tell you what it thinks you said so you can make corrections. Wow!

Where you are: JegsWorks > Lessons > Computer Basics
	1. Computer Types
	2. Applications
	3. Input Intro Keyboard: framed no frames Pointing Devices Terminals Multimedia Data Automation Data Accuracy Quiz
	4. Processing
	5. Output
	6. Storage
	7. Computer to Computer
	8. System Software
	9. Programming

	10. What You See
	11. Hands On!
	12. On Your Own

	Search Glossary Appendix

How do they change voice to data??

1.	Convert voice sound waves to digital form (digital signal processing -DSP)
2.	Compare digitized voice input to stored templates
3.	Check grammar rules to figure out words
4.	Present unrecognized words for user to identify

Types of Voice Recognition systems

Speaker dependent system The software must be trained to recognize each word by each individual user. This might take hours of talking the dictionary into the computer, to be optimistic.

Speaker independent system The software recognizes words from most speakers with no training. It uses templates. A strong accent would defeat the system, however.

Discrete speech recognition The speaker must pause between words for the computer to tell when a word stops.

Continuous speech recognition The speaker may use normal conversational flow.

Natural language The speaker could say to the computer "How soon can we ship a dozen of product #25 in blue to Nashville?" - and get an answer!!

Science fiction has come to life!!!

Video Input

camera A digital camera takes still photos but records the pictures on computer disks or memory chips. The information contained can be uploaded to a computer for viewing.

camcorder gif A video camera or recorder (VCR) can record data that can be uploaded to the computer with the right hardware. Though it is not digital data, you can still get good results with the right software.
Both of these take huge amounts of storage. Photos make for very large files.

Quickcam - a timy camera for your computer A web cam is a tiny video camera designed especially to sit on your computer. It feeds pictures directly to the computer - no tape or film to develop. Of course you are limited by the length of the cable that connects the camera to the computer. But like any camera, it will take a picture of what you point it at!

So what do people do with a web cam? They use it for video conferencing over the Internet. They show the world what's going on outside their window (weather, traffic). They take digital pictures and make movies- family, pets, snow storms, birthday parties, whatever.

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~~ 1 Cor. 10:31 ...whatever you do, do it all for the glory of God. ~~

Last updated: 22 Jan 2008