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Terms for computer junkies
PUMP up your computer-related vocabulary! Load your brains with these frequenty used i-terms.
Compression artifact: It is the fuzz or distortion in a compressed image or sequence of video images. When a photo is compressed into a JPEG format, some data is lost, which is why this type of compression is called lossy compression. The data that is lost is considered to be not necessary for the viewer to perceive or perhaps not perceivable in any case. In creating a JPEG, if you wish to have a smaller file size regardless of quality, then the result may introduce perceivable compression artifacts.
However, if you wish to maintain the quality of the photo and have a larger file size, then the viewer may not notice any artifacts. Artifacts are more evident on a computer image than in a printed photograph.
A digital video file is also compressed and, depending on the amount of compression, may present artifacts. A digital video file has the same fuzzy edges and distortion of images as a still image (JPEG) file may have. The break up of the video into large digital pixels and jerkiness in the video stream are examples of compression artifacts.
Computed Dental Radiography: CDR is a technology for capturing a computerized image or radiograph of your teeth and gums that requires 90 per cent less radiation than conventional x-ray film. CDR images are captured by sensors placed in the mouth that relay data to an attached computer, where the images are stored for viewing. Unlike conventional dental x-rays, CDR images can also be enlarged up to 300 times normal size to aid in diagnosis. They can also be manipulated for contrast and the colors can be adjusted. Images are captured instantly and do not require film developing and mounting.
X (CD access time): In compact disc, and digital versatile disc (DVD) technology, X is a base multiplier that expresses the speed with which data could be read (the read access time) from the compact disc in its original version, which was 150 kilobytes per second. As successively faster CDs arrived, manufacturers adopted the convention of indicating the read time in terms of the original speed. Thus, a 2X CD had a read access time of 300KBps and so forth. Our table relates each common drive speed to its read access time. It also shows the range of revolutions per minute (RPM) used to make the read access time possible.
There are only minor increases in read access time as one moves from the 24X, 32X, and 40X drives. Higher rotation speeds are prone to noise and vibrations and may cause performance to vary from drive to drive.
It seems unlikely, because of these vibrations and performance variations, that read access times will increase much above present levels. Even though a hard drive can reach much faster speeds of rotation, its enclosure stabilizes the entire mechanism and therefore avoids much of the noise and vibration inherent in the open CD-ROM drive.
Counterfeit detector pen: This pen is a felt tip pen containing an iodine solution that can be used to help identify computer-generated counterfeit bills. According to US Secret Service data, “funny money” generated by criminals using computers and ordinary printers accounted for only one-half of 1 per cent of the counterfeit bills confiscated in 1995.
By the year 2000, that figure had risen to 45 per cent and is still going up. Detector pens, although not fool-proof, are an effective way to identify computer-generated counterfeit bills because the iodine solution in a detector pen reacts with starch, which is commonly found in the wood-based copy paper used by most printers.
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