*** PC VIDEO: GLOSSARY *** GLOSSARY OF COMMON VIDEO TERMS VIDEO GLOSSARY: A ActionMedia(R) Board: Intel I750(R)-based board set that performs realtime compression and full-screen playback. Active Pixel Region: On a computer display, the area of the screen used for actual display of pixel information. ADPCM: Adaptive Differential Pulse Code Modulation. An encoding format for storing audio information in a digital format. Adaptive Compression: Data compression software that continually analyzes and compensates its algorithm, depending on the type and content of the data and the storage medium. Additive Color: Color produced by "adding" colors, usually the combination of red, green and blue. Algorithm: In compression software refers to a specific formula used to compress or decompress video. Aliasing: A form of image distortion associated with signal sampling. A common form of aliasing is a stair-stepped appearance along diagonal and curved lines. Analog: The representation of numerical values by physical variables such as voltage, current, etc. Analog devices are characterized by dials and sliding mechanisms. See also Digital. Analog Video: A video signal that represents an infinite number of smooth gradations between given video levels. By contrast, a digital video signal assigns a finite set of levels. See also Digital Video. Anamorphic: Unequally scaled in vertical and horizontal dimensions. Antialiasing: A form of interpolation used when combining images; pixels along the transitions between images are averaged to provide a smooth transition. ANSI: American National Standards Institute. A standards-setting, non-government organization which develops and publishes standards for voluntary use in the United States. API: Application Programmers Interface. Loosely used to describe the point at which software modules or layers meet and interconnect. Artifact: An unintended, unwanted visual aberration in a video image. ASCII: American Standard Code for Information Interchange. The most popular coding method used by small computers for converting letters, numbers, punctuation, and control codes into digital form. Aspect Ratio: The relationship of width and height. When an image is displayed on different screens, the aspect ratio must be kept the same to avoid "stretching" in either the vertical or horizontal direction. For VGA and Indeo(TM) video technology, the aspect ratio is 4:3 yielding 160X120, 320X240 and 640X480 sizes. Asymmetrical Compression: A system which requires more processing capability to compress an image than to decompress an image. It is typically used for the mass distribution of programs on media such as CD-ROM, where significant expense can be incurred for the production and compression of the program but the playback system must be low in cost. Audio: Sound for multimedia systems. Audible range is typically from 30Hz to 20,000Hz (20KHz). Authoring System: Software which helps developers design interactive courseware easily, without the painstaking detail of computer programming. AVI: Audio Video Interleaved. File format for digital video and audio under Windows. File format is cross-platform compatible, allowing *.AVI video files to be played under other operating systems. AVK: Audio Video Kernel. DVI system software designed to play motion video and audio across hardware and operating system environments. AVSS: Audio-Video Support System. DVI system software for DOS. It plays motion video and audio. VIDEO GLOSSARY: B Bandwidth: Usually used in context to refer to the amount of data/unit of time that must move from one point to another - such as from CD-ROM to processor. Bitmap: Representation of characters or graphics by individual pixels arranged in row (horizontal) and column (vertical) order. Each pixel can be represented by one bit (simple black and white) or up to 32 bits (high-definition color). Bitmapped Graphics: Images which are created with matrices of pixels, or dots. Also called raster graphics. Bit Specifications: Number of colors or levels of gray that can be displayed at one time. Controlled by the amount of memory in the computer's graphics controller card. An 8-bit controller can display 256 colors or levels of gray; a 16-bit controller, 64,000 colors; a 24-bit controller, 16.8 million colors. BPP: Bits Per Pixel. The number of bits used to represent the color value of each pixel in a digitized image. BPS: Bits Per Second. The number of bits transferred in a data communications system. Measures speed. Brightness: The balance of light and dark shades in an image. VIDEO GLOSSARY: C CCITT: Consultative Committee for International Telephone and Telegraph. An international standards organization dedicated to creating communications protocols that will enable global compatibility for the transmission of voice, data, and video across all computing and telecommunications equipment. CD: Compact Disc. A standard medium for storing digital data in machine readable form, accessible with a laser-based reader. Readers are typically referred to as CD-ROM drives. CD-I: Compact Disc-Interactive. A compact disc format (developed by NV Philips and Sony Corporation) which provides audio, digital data, still graphics and limited motion video. CD-ROM: Compact Disc-Read Only memory. A 4.75 inch laser-encoded optical memory storage medium. Uses CLV format and can hold about 550 megabytes of data. CD-ROM XA: Compact Disc-Read Only Memory eXtended Architecture. An extension of the CD-ROM standard, billed as a hybrid of CD-ROM and CD-I and promoted by Sony and Microsoft. The extension adds ADPCM audio to permit the interleaving of sound and video data to animation and with sound synchronization. It is an essential component of Microsoft's plan for multimedia computers. CDTV: Commodore Dynamic Total Vision. Consumer multimedia system from Commodore that includes CD-ROM/CD audio player, Motorola 68000 processor, 1MB RAM, and 10-key infrared remote control. CGA: Color Graphics Adapter. A low-resolution video display standard, invented for the first IBM PC. CGA pixel resolution is 320x200. CGM: Computer Graphics Metafile. A standard format that allows for the interchanging of graphics images. Chroma, Chrominance: The color portion of the video signal that includes hue and saturation information. Requires luminance, or light intensity, to make it visible. CIE: Commission International de l'Eclairage. The international commission on illumination. Developer of color matching systems. CLV: Constant Linear Velocity. Spiral format of audio compact disks and some video laser disks. CMYK: Cyan, Magenta, Yellow, and black. The four process colors that are used in four-color printed reproduction. CODEC: Compression/decompression of video in DVI(R). Color Balance: The process of matching the amplitudes of red, green and blue signals so the resulting mixture makes an accurate white color. Color Cycling: A means of simulating motion in a video by changing colors. Color Keying: To superimpose one image over another for special effects. Composite Video: A video signal format that includes the complete visual waveform, including : chrominance (color), luminance (brightness), blanking pedestal, field, line, color sync pulses and field qualizing pulses. Compound Document: A file that has more than one element (text, graphics, voice, video) mixed together. Compressed Video: A digital video image or segment that has been processed using a variety of computer compression algorithms and other techniques to reduce the amount of data required to accurately represent the video content. Compression: The translation of data (video, audio, digital, or a combination) to a more compact form for storage or transmission. Continuous Tone: An image that has all the values (0 to 100%) of gray (black and white) or color in it. A photograph is a continuous tone image. Contrast: The range between the lightest tones and the darkest tones in an image. Convergence: In an RGB monitor, where red, green, and blue signals all "converge" in one pixel. At full brightness, the RGB pixel in convergence would be white. CSC: Computer Support Collaboration. Describes computers that enhance productivity for people working in groups. Application examples include video conferencing, video mail, and shared workspaces. VIDEO GLOSSARY: D DAT: Digital Audio Tape. A consumer recording and playback medium for high quality audio. Data Rate: The speed of a data transfer process, normally expressed in bits per second or bytes per second. DCT: Discrete Cosine Transform. A form of coding used in most of the current image compression systems for bit rate reduction. Decompression: To reverse the procedure conducted by the compression software algorithm to return data to its original size and condition. Density: The degree of darkness of an image. Also, percent of screen used in an image. Delivery System: The equipment used by end users to run or "play" an interactive program. Device Driver: Software that tells the computer how to talk to a peripheral device, such as a videodisc player or printer. Delta Frame: Also called Difference Frame. Contains only the pixels different from the preceding Key Frame. Delta Frames reduce the overall size of the video clip to be stored on disk. See also Key Frame. Digital: A method of signal representation by a set of discrete numerical values, as opposed to a continuously fluctuating current or voltage. See also Analog. Digital Video: A video signal represented by computer-readable binary numbers that describe a finite set of colors and luminance levels. Digitization: Process of transforming analog video signal into digital information. Dithering: Blurred transition from one color to another in a computer picture. DVI(R): Digital Video Interactive. Intel's original name for its PC-based digital video technologies. This name has been replaced on the software side with Indeo(TM) video technology, on the retail side with Smart Video Recorder and on the hardware side with I750(R) Processors. VIDEO GLOSSARY: E EGA: Enhanced Graphics Adapter. A display technology for the IBM PC. It has been replaced by VGA. EGA pixel resolution is 640x350. EISA: Extended Industry Standard Architecture. A 32-bit bus standard that supports the features of IBM's Micro Channel Architecture (MCA). EISA requires a special card for 32-bit operations but maintains compatibility with the older ISA. Encoding: The process of creating a compressed file. VIDEO GLOSSARY: F Field: One-half of a complete video frame, consisting of every other analog scan line. Filtering: A process used in both analog and digital image processing to reduce bandwidth. Filters can be designed to remove information content such as high or low frequencies, for example, or to average adjacent pixels, creating a new value from two or more pixels. FPS: Frames Per Second. Film is 24 FPS, NTSC is 30 FPS and PAL/SECAM is 25 FPS. Fractals: Along with raster and vector graphics, a way of defining graphics in a computer. Fractal graphics translate the natural curves of an object into mathematical formulas, from which the image can later be constructed. Frame: A single, complete picture in video or film recording. A video frame consists of two interlaced fields of either 525 lines (NTSC) or 625 lines (PAL/SEACAM), running at 30 frames per second (NTSC) or 25 frames per second (PAL/SEACAM). Frame Grabber: A device that "captures" and potentially stores one complete video frame. Also known as Frame Storer. Frame Rate: The speed at which video images are displayed. Full-Motion Video: Video reproduction at 30 frames per second (NTSC-original signals) or 25 frames per second (PAL-original signals). VIDEO GLOSSARY: G Gain: The increase in signaling power as an audio signal is boosted by an electronic device. It is measured in decibels. Gradient: In graphics, having an area smoothly blend from one color to another, or from black to white, or vice versa. Gray Scale: The spectrum, or range, of shades of black that an image has. GUI: Graphical User Interface. An application, such as Microsoft Windows, that lies on top of other applications and provides a user interface based on graphical icons. VIDEO GLOSSARY: H HDTV: High Definition TV. A proposed standard, recommending the doubling of the current 525 lines per picture to 1050 lines and increasing the screen aspect ratio (width:height) from the current 12:9 to 16:9, which would create a television screen shaped more like a movie screen. High Resolution: An adjective describing improvement in image quality as a result of increasing the number of pixels per square inch. Called hi-res for short. High Sierra Format: A standard format for placing files and directories on CD-ROM, revised and adopted by the International Standards Organization as ISO 9660. HSB: Hue Saturation Brightness. With the HSB model, all colors can be defined by expressing their levels of hue (the pigment), saturation (the amount of pigment) and brightness (the amount of white included), in percentages. Hz: Abbreviation for Hertz; cycles per second. VIDEO GLOSSARY: I I750(R): Name of the programmable video processor family from Intel. IMA: Interactive Multimedia Association. Formed in 1991 (rooted in IVIA, Interactive Video Industry Association), an industry association chartered with creating and maintaining standard specifications for multimedia systems. Image: The computerized representation of a picture or graphic. Image Resolution: The fineness or coarseness of an image as it was digitized, measured in Dots Per Inch (DPI), typically from 200 to 400 DPI. Indeo(TM): Intel's compression/decompression algorithm for scalable software playback video. Intel licenses Indeo(TM) technology to companies such as Microsoft that integrate it into products such as Microsoft's Video For Windows. Indeo(TM) technology can record 8-, 16- or 24-bit sequences and store the sequence as 24-bit for scalability on higher power PCs. Interactive Video: The fusion of video and computer technology. A video program and a computer program running in tandem under the control of the user. In interactive video, the user's actions, choices, and decisions affect the way in which the program unfolds. Interframe Coding: Compression techniques which track the differences between frames of video. Results in more compression over a range of frames than intraframe coding. Interlace: Scheme to display a video image by displaying alternate scan lines in two discrete fields. Interpolation: The process of averaging pixel information when scaling an image. When the size of an image is reduced, pixels are averaged to create a single new pixel; when an image is scaled up in size, additional pixels are created by averaging pixels of the smaller image. ISA: Industry Standard Architecture. The architectural standard for the IBM XT (8-bit) and the IBM AT (16-bit) bus designs. In ISA systems, an adapter is added by plugging the card into one of the 8-bit or 16-bit expansion slots. ISO: International Standards Organization. Worldwide group responsible for establishing and managing various standards committees and expert groups, including several image-compression standards. ISV: Independent Software Vendor. Company which develops and sells application tools and/or software titles. ISVYVU9: Recording format for uncompressed Indeo(TM) video technology using VidCap under Microsoft's Video For Windows. VIDEO GLOSSARY: J-K JPEG: Joint Photographic Expert Group. High-quality, single-picture spatial compression. Uses DCT algorithm (Discrete Cosine Transfer). Has been adapted to video but provides no frame compression. See also Delta Frame. Key Frame: A video frame in which all of the video information is recorded in compressed fashion. If the clip has a large amount of motion, better playback will occur with every frame being a Key Frame. If there is very little motion, such as a narrator, a higher number of Delta Frames will give satisfactory playback. In general, making every 3rd frame a Key Frame is a good choice with the current Indeo(TM) technology algorithm. See also Delta Frame. VIDEO GLOSSARY: L LAN: Local Area Network. Lossless Compression: Ensures that the original data is exactly recoverable with no loss in image quality. Lossy Compression: The original data is not completely recoverable. Although image quality may suffer, many experts believe that up to 95 percent of the data in a typical image may be discarded without a noticeable loss in apparent resolution. Luminance: Brightness; one of the three image characteristics coded in composite television (represented by the letter Y). May be measured in lux or foot-candles. VIDEO GLOSSARY: M MAN: Metropolitan Area Network. MCA: Media Control Architecture. System-level specification developed by Apple Computer for addressing various media devices (videodisc/videotape players, CD players, etc.) to its Macintosh computers. MCI: Media Control Interface. Platform-independent multimedia specification published by Microsoft Corporation and others in 1990. Provides a consistent way to control devices such as CD-ROMs and video playback units. Media Clip: A video segment usually interleaved with an audio segment. Micro Channel: Personal computer bus architecture introduced by IBM in some of its PS/2 series microcomputers. Incompatible with original PC/AT (ISA) architecture. MIDI: Musical Instrument Digital Interface. An industry-standard connection for computer control of musical instruments and devices. MIPS: Millions of Instructions Per Second. Refers to a computer processor's performance. MOPS: Millions of Operations Per Second. In the case of DVI technology, more MOPS translate to better video quality. Intel's video processor can perform multiple video operations per instruction, thus the MOPS rating is usually greater than the MIPS rating. Motion Video: Video that displays real motion by displaying a sequence of images (frames) rapidly enough that the eyes see the image as a continuously moving picture. MPC: Multimedia PC. A specification developed by the Multimedia Council. It defines the minimum platform capable of running multimedia software. PCs carrying the MPC logo will be able to run any software that also displays the MPC logo. MPEG: Motion Picture Expert Group. Similar to spatial compression of JPEG, but adds frame-to-frame temporal compression. Compaction is typically 3 times better than video JPEG. Produces VCR quality video. MPEGII yields broadcast quality video. Multimedia: Refers to the delivery of information that combines different content formats (motion video, audio, still images, graphics, animation, text, etc.). Multimedia Computing: Refers to the delivery of multimedia information delivered via computers. VIDEO GLOSSARY: N-O NLM: Network Loadable Module. NOS: Network Operating System. NTSC: National Television Systems Committee of Electronic Industries Association (EIA) that prepared the standard of specifications approved by the Federal Communications Commission in 1953 for commercial broadcasting. NTSC is the standard for the U.S., Canada, Japan, Central America, 1/2 of the Caribbean & 1/2 of South America. NTSC Format: A color television format having 525 scan lines; a field frequency of 60 Hz; a broadcast bandwidth of 4 MHz; line frequency of 15.75 KHz; frame frequency of 1/30 of a second; and a color subcarrier frequency of 3.58 MHz. OEM: Original Equipment Manufacturer. Company which develops, produces and sells computer and consumer hardware. OLE: Object Linking & Embedding. Allows users to insert multimedia elements (including video) into Windows applications. Overlay: The ability to superimpose computer graphics over a live or recorded video signal and store the resulting video image on videotape. It is often used to add titles to videotape. VIDEO GLOSSARY: P-Q PAL: Phase Alteration Line. Video format used in most of Western Europe, Australia and other countries. PAL Format: 625 lines of resolution at 25 frames per second. PCM: Pulse Code Modulation. The most common method of encoding an analog signal into a digital bit stream. A digitization technique, not a universally accepted standard. Pixels: An abbreviation for picture element. The minimum raster display element, represented as a point with a specified color or intensity level. One way to measure picture resolution is by the number of pixels used to create the image. PLV: Production Level Video. An asymmetric compression algorithm that runs on I750(R) processors. Source video is sent to a Digital Compression Facility (DCF), where a supercomputer processes it frame-by-frame to provide superior image color and quality. PLV was designed by Intel and is available with the ActionMedia(R)II board. PX64: Similar to MPEG, but adapted to slower bit rate. Typically used for video conferencing over an ISDN phone line. Quicktime: Apple Computer's video environment (like Microsoft's Video For Windows). Quicktime video files must be converted to *.AVI format to run under Microsoft's Video For Windows. Indeo(TM) video technology is supported under MacOS. VIDEO GLOSSARY: R Raster Graphics: Images defined as a set of pixels or dots in a column-and-row format. Also called bit-mapped graphics. Real-time: In computing, refers to an operating mode under which data is received and processed and the results returned so quickly as to seem instantaneous. Resolution: The number of pixels per unit of area. A display with a finer grid contains more pixels and has a higher resolution, capable of reproducing more detail in an image. RGB: Red-Green-Blue. A type of computer display output signal comprised of separately controllable red, green and blue signals. The other technique for output display is composite video, which typically offers less resolution than RGB. RIFF: Resource Interchange File Format. Platform-independent multimedia specification (published by Microsoft and others in 1990) that allows audio, image, animation, and other multimedia elements to be stored in a common format. See also Media Control Interface (MCI). RLE: Run Length Encoding. Microsoft's video compression algorithm for base level multimedia PCs. Compresses 8-bit sequences only. Playback is also in 8 bit and isn't scalable for higher power PCs. RS170: The EIA (Electronics Industries Association) standard for the combination of signals required to form NTSC monochrome (black and white) video. RS170A: The EIA standard for the combination of signals required to form NTSC color video. It has the same base as RS170, with the addition of color information. RTV: Real Time Video. Single step compression of video. VIDEO GLOSSARY: S Sampling: The first step in the process of converting an analog signal into a digital representation. This is accomplished by measuring the value of the analog signal at regular intervals called samples. These values are then encoded to provide a digital representation of the analog signal. Saturated Colors: Strong, bright colors (particularly reds and oranges) which do not reproduce well on video; they tend to saturate the screen with color or bleed around the edges, producing a garish, unclear image. Scalable Video: With respect to Indeo(TM) video technology, it is a playback format that can determine the playback capabilities of the computer on which it is playing. Using this information, it allows video playback to take advantage of high-performance computer capabilities while retaining the ability to play on a lower performance computer. Scalability: The ability to vary the information content of a program by changing the amount of data that is stored, transmitted or displayed. In a video image, this translates into creating larger or smaller windows of video on screens (shrinking effect). Scaling: Process of uniformly changing the size of characters or graphics. SECAM: "SEquential Couleur A Memoire" (sequential color with memory). Video format used in France, Eastern Europe, F.S.U and other countries. SECAM Format: 625 lines of resolution at 25 frames per second. Smart Video Recorder: Intel's PC Video single-step compression, real-time video capture card that uses Indeo(TM) technology and an Intel I750(R) processor. SMPTE Time Code: An 80-bit standardized edit time code adopted by SMPTE, the Society of Motion Picture and Television Engineers. See also Time Code. Subsampling: Bandwidth reduction techniques which reduce the amount of digital data used to represent an image. Part of a compression process. S-Video: Type of video signal used in Hi8, S-VHS and some laserdisc formats. It transmits luminance and color portions separately, using multiple wires. S-Video avoids composite video encoding, such as NTSC, and the resulting loss of picture quality. Also known as Y-C Video. Symmetrical Compression: A compression system which requires equal processing capability for Compression and decompression of an image. This form of compression is used in applications where both compression and decompression will be utilized frequently. Examples include: still-image databasing, still-image transmission (color fax), video production, video mail, videophones, and videoconferencing. VIDEO GLOSSARY: T-U Teleconference: A general term for a meeting not held in person. Usually refers to a multi-party telephone call, set up by the phone company or private source, which enables more than two callers to participate in a conversation. The growing use of video allows participants at remote locations to see, hear, and participate in proceedings, or share visual data ("video conference"). TIFF: Tagged Image File Format. A bit map file format for describing and storing color and gray-scale images. Time Code: A frame-by-frame address code time reference recorded on the spare track of a videotape or inserted in the vertical blanking interval. It is an eight-digit number encoding time in hours, minutes, seconds, and video frames (e.g.:02:04:48:26). Tint: Another name for hue. Trichromatic: The technical name for RGB representation of color to create all the colors in the spectrum. Ultimedia: IBM's product that supports both Ultimotion and Indeo(TM) video technology. Ultimotion: IBM's video compression algorithm. Although IBM supports Indeo(TM) video technology in OS/2 and Windows systems, IBM feels several OS/2 vertical applications are adequately served by the Ultimotion algorithm. Ultimotion does not offer software scalable playback or single step compression. VIDEO GLOSSARY: V VAR: Value Added Reseller. A company which resells hardware and software packages to developers and/or end-users. VCR: Video Cassette Recorder. An analog magnetic recording and playback machine. Generally used for recording and viewing full-motion video. VDI: Video Device Interface. A software driver interface that improves video quality by increasing playback frame rates and enhancing motion smoothness and picture sharpness. VDI was developed by Intel and will be broadly licensed to the industry. VDRV: Variable Data Rate Video. In digital systems, the ability to vary the amount of data processed per frame to match image quality and transmission bandwidth requirements. DVI symmetrical and asymmetrical systems can compress video at variable data rates. Vector Graphics: Images defined by sets of straight lines, defined by the locations of the end points. VESA: Video Electronics Standards Association. A 32-bit local bus standard that is compatible with both ISA and EISA cards. Many manufacturers of local bus adapters use this standard because of its speed. VidCap: Microsoft's Video For Windows program to capture video input to RAM or hard disk memory. VGA: Video Graphics Array. Standard IBM PC video display. Provides medium resolution text and graphics. VGA pixel resolution is 640X480. Video1: The default video compression algorithm in Microsoft's Video for Windows. Can produce 8- or 16-bit video sequences. VIDEO GLOSSARY: W-X WAN: Wide Area Network. XGA: EXtended Graphics Adapter. New IBM graphics standard that includes VGA and supports higher resolutions, up to 1024 pixels by 768 lines interlaced. VIDEO GLOSSARY: Y Y/C: See S-Video YUV: A color encoding scheme for natural pictures in which luminance and chrominance are separate. The human eye is less sensitive to color variations than to intensity variations. YUV allows the encoding of luminance (Y) information at full bandwidth and chrominance (UV) information at half bandwidth. YUV9: The color encoding scheme used in Indeo Video Technology. The YUV9 format stores information in 4x4 pixel blocks. Sixteen bytes of luminance are stored for every 1 byte of chrominance. For example, a 640x480 image will have 307,200 bytes of luminance and 19,200 bytes of chrominance. ------------------------------------------------------------------------------ End of file Intel FaxBack # 8006 19 August 1994