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Columns in Word
Merging Two Documents in Word
Footers in Word
Megapixels Do We Need Them?
Aliasing -- Distortion in a video image. In analog video, this is caused by interference between different signal frequencies; in digital video, its caused by poor sampling in the digitizing process. On the screen, the result is that angled lines look jagged.
Anti-Aliasing is the process of smoothing out those jagged lines.
Artifacts Defects in the video signal usually caused by compression errors.
Aspect Ratio The ratio of a screens width to height. In standard television, this is 4:3; in widescreen, its usually 16:9
AVI (Audio video Interleave). Microsofts format for digital audio and video files.
Chromakeying The process of layering one video signal over another, but only on a specific color; also called blue screen or green screen, depending on the color being replaced. This is the process that lets your local TV weather person stand in front of weather maps and satellite images.
Chrominance (or Chroma) The color portion of a video signal.
Cinepak A video compression algorithm often used on CD-ROMs.
CODEC (Coder/DECoder) The thing that converts analog signals to digital and vice versa.
Compression The process of reducing the size of a data file, usually accomplished through software processing. Compressed files save storage space and reduce transmission times.
Cut The instantaneous transition from one clip to another
DAC Digital to Analog Converter
Desktop Video Editing video on a computer with the use of add-on video hardware and software
Digital Video A recording process that captures each image frame as binary data
DV The digital VCR format, developed jointly by several video and computer manufacturers for mini-cassettes. DVCAM and Digital 8 are consumer versions of the format. DVCPRO and DVCPRO50 are professional broadcast versions.
DVD (Digital Versatile Disk) A high-density version of the original compact disk. It holds seven times more information on a side, about 4.38 GB
Fade In (or Fade Up) A transition from a blank screen to an image.
Fade Out (or Fade Down or Fade To Black) A transition from an image to a blank (usually black) screen.
Frame One full screen of dieo. In broadcast television, each frame is made of two interlaced fields. The first field contains all the odd-numbered lines and the second field contains all even-numbered lines.
Frame Rate Broadcast television (NTSC) has 30 frames per second. Most computers these days are powerful enough to run video at this rate. However, you may choose to use a slower rate (15 or 10 frames per second) if youre tight on storage space, or if you want your video to more easily stream down the Internet. Computer graphics may use frame rates as high as 100 frames per second
IEEE 1394 (or Firewire) A high-speed, low-coast digital interface developed by Apple.
Lossless Compression A compression that returns all the original data when uncompressed
Lossy Compression Compression algorithms that throw out insignificant data in the compression process
Luminance The part of the video signal that holds information about the image brightness
Mask A blank graphic that covers a portion of the screen to allow another image to show through.
Matte The process of using an electronic mask to cover part of a video image and replace it with another image
MPEG (Moving Picture Experts Group) The industry group that
develops the technical specifications for digital video. The term also
refers to the digital video compression standards that the group has developed.
MPEG files can be decoded by special hardware or software. MPEG achieves
a high compression rate by storing only the changes from one frame to another,
instead of each entire frame.
MPEG-1 This standard provides a video resolution of 352 x
240 at 30 frames per second. This produces video quality slightly below
the quality of a home VHS videotape.
MPEG-2 (used by DVDs) This standard offers resolutions of
720 x 480 at 60 frames per second, with full CD-quality audio. This is
sufficient for all the major TV standards, including NTSC and new high-definition
television.
NTSC The National Television Standards Committee is the group formed by the FCC to set the technical specifications for broadcast television. NTSC also refers to U.S. television standards; 525 scan lines interlaced at 60 fields, making 30 frames per second.
Screen Size In broadcast television, a picture is always 525 scan lines tall (or 525 pixels). Because some of these lines are hidden by the edge of the TV screen, 480 lines are considered to be the "safe" area of a TV image. On your computer, 480 x 640 pixels corresponds to that picture size.
Streaming Media thats viewed as its received, as opposed to a download, where the entire program would be transmitted before viewing begns.
Timeline (or Story Line) 1) The sequence of clips you put together when youre editing; 2) In editing software, the graphic representation of the assembled audio and video clips.
Transition The change from one clip to another, such as a cut, dissolve, wipe or fade.
Video For Windows Microsofts software for time-based media; similar to QuickTime