Presentation Transcript

1. Computer Basics

   Lesson 3 - Terminals
2. Terminals A terminal consists of a keyboard and a screen so it can be considered an input device. Terminals are also called: Display Terminals Video Display Terminals or VDT A dumb terminal has no ability to process or store data.
3. Terminals An intelligent, smart, or programmable terminal can process or store on its own, at least to a limited extent. PCs can be used as smart terminals. A point-of-sale terminal (POS) is an example of a special purpose terminal. These have replaced the old cash registers in nearly all retail stores. They can update inventory while calculating the sale. Credit card readers Fingerprint scanners

4. Computer Basics

   Lesson 3 - Multimedia
5. 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.
6. Sound Input Recording sounds for your computer requires special equipment such as: 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.
7. Voice Input 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.
8. Voice Input 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."
9. 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.
10. 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.
11. Voice Recognition Systems 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!!
12. Video Input 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. 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.
13. Video Input 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. So what do people do with a web cam? They use it for video conferencing over the Internet or Skype video phone calls. 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.