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Appendix A | Appendix B | Appendix C | Glossary | Index | Legal Stuff | License

Glossary

A | B | C | D | E | F | G | H | I | K | L | M | N | O | P | Q | R | S | T | U | V | W


A/B Slider ­ slider on the Dynamic Preview window which allows you to compare your processing and/or compression settings by moving it back and forth in real-time.

Adaptive Noise Reduction Filter ­ "intelligent" noise filtering that analyzes each pixel and applies an appropriate filter (mean or median) to remove the noise. Normally maintains edge detail while still improving compression.

Adaptive Data Rate Control ­ Media Cleaner's two-step process of analyzing and then compressing movies to an optimal data rate.

Analog-to-Digital Converter ­ a chip that takes an analog signal, such as NTSC video, and converts it into a digital signal. Analog-to-digital converters are used on capture cards to change the NTSC video into a format that the computer can better manipulate and store. May also be called "A-to-D converters."

Architecture ­ see "Multimedia Architecture"

Audio Fades ­ a feature that adjusts the volume over time to begin and/or end a movie with silence.

Audio Interleave Factor ­the size of the audio "chunks" stored within a movie. QuickTime 2.1 and later automatically uses a 1 second interleave for the first second of the movie, and a 1/2 second interleave throughout the rest of the movie.

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Bandwidth ­ the amount of information that can be sent, processed, etc., in a given amount of time. For example, a double speed CD-ROM drive has a bandwidth of 300 KBps; a 28.8 baud modem has a bandwidth of approximately 2.5 KBps.

Batch Compression ­ grouping two or more movies together to be compressed sequentially, so that each compression doesn't need to be started manually.

Batch List ­ a specific list of movies to be batch compressed, as well as the settings with which each movie will be processed.

Batch Log File ­ a text file which reports the results of each compression, including any problems that occurred. It may be viewed with a text program such as Simple Text.

Blur ­ a filter which averages together pixels to minimize subtle frame-to-frame differences. Normally, you will get better results with the Adaptive Noise Reduction filter.

Bottlenecks ­ points in a system that are slower than the rest of the system, causing overall delays. In the Internet, bottlenecks are often caused by localized problems, such as overloaded switching complexes, etc.

Burn ­ changing a text or sprite track into an image in the video track. Often used as a work-around to the fact that QuickTime for Windows 2.1.2 does not support text or sprite tracks.

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Cinepak ­ a commonly-used QuickTime codec for CD-ROM video compression. Allows temporal and spatial compression, as well as data rate limiting.

Chapter List ­ a QuickTime feature which allows users to click on a pop-up to display the first text track of a movie. Selecting text from this pop-up shows the viewer the part of the movie associated with the selected text.

ClearVideo ­ Iterated System's fractal-based codec for low data rate video. Implemented in QuickTime, RealMedia and Video for Windows.

CLUT ­ abbreviation for Color Lookup Table. See Palette.

Codec ­ also called a compressor. A codec is a compression/decompression software component which translates video or audio between its uncompressed form and the compressed form in which it is stored. Currently, the most commonly used video codec for CD-ROM is Cinepak.

Codec Central ­ a section of Terran Interactive's web site which contains current information and pricing on the various codecs and multimedia architectures. To get there, select "Codec Central" in the Media Cleaner Internet menu, or visit www.codeccentral.com

Color Depth ­ the possible range of colors that can be used in a movie or image. There are four choices with video:

gray scale - black, white, and shades of gray (8-bit)
256 colors (8-bit)
thousands of colors (16-bit)
millions of colors (24-bit)

256 colors uses a palette; none of the other color depths do.

Color Lookup Table ­ see Palette.

Color Table ­ see Palette

Computer ­ a $2,000+ device which still can't produce the same video quality as a $100 television. Hopefully this will change...

Compressor ­ see Codec

CPU-Intensive ­ describes processes which use large amounts of processor time. CPU-intensive processes tend to slow the computer down while they are running, and not work well on slower machines.

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Data Rate ­ the amount of information per second used to represent a movie, often expressed in KBps. A single speed CD-ROM movie is usually made at a data rate of 100 KBps, and a double speed CD-ROM about 200 KBps. The data rate of uncompressed NTSC video is about 27 Megabytes per second.

Data Rate Limiting ­ the ability of a program or codec to control the size of the final compressed movie so that it meets the specified data rate. See also "Adaptive Data Rate Control".

Data Rate Spikes ­ short sections of a movie that have significantly higher data rates than the rest of the movie. If not properly managed, spikes may cause dropped frames or other problems at certain points of the movie.

Deinterlace ­ to remove the interlacing artifacts caused by the two fields-per-frame nature of video.

Delta Frames ­ frames which contain only the changes from the previous frame. Delta frames are created by codecs which use temporal compression. Delta frames are also called "difference frames."

Difference Frames ­ see "Delta Frames."

Download ­ to copy a file from a server or network to your machine.

DVD ­ acronym which doesn't mean anything. (DVD was originally short for "Digital Video Disc", but then DVD expanded past just video. Sometimes explained as "Digital Versatile Disc.") See "DVD-ROM" and "DVD-Video."

DVD-ROM ­ a version of the DVD disc format for computers which should eventually replace CD-ROMs. Similar to an 8x, 4.7 - 17 Gigabyte CD-ROM, DVD-ROM does not require MPEG.

DVD-Video ­ a version of the DVD disc format that will be used for storage of prerecorded movies and should replace VHS. DVD-Video uses MPEG.

Dynamic Preview ­ Media Cleaner feature which lets you see the effects of your processing and/or compression settings in real-time.

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Edge Blanking ­ the black part of the video signal normally outside a TV's image. Most capture cards include some amount of edge blanking around the captured image. Commonly referred to as "edge noise" or sometimes as "overscan".

EMBED Tag ­ an HTML code that specifies how a graphic or movie will be included within your WWW page.

Event Handling ­ the process in which programs look for other system activity and respond to it. Media Cleaner uses very limited event handling while compressing. This means it finishes what it is currently doing before checking if the mouse has moved. This behavior can cause delays between when you first move the mouse and when control is returned to you, but speeds up the compression process.

Export Module ­ an Adobe Premiere plug-in which allows files to be transferred from Premiere to Media Cleaner for optimization and compression.

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Fades ­ see "Audio Fades" and "Video Fades."

Fast Start ­ a progressive download feature of QuickTime which allows movies to be viewed inline before the whole movie has been fully downloaded.

Field ­ half of an interlaced video frame consisting of the odd or the even image lines. Alternating video fields are drawn every 1/60th of a second in NTSC video to create the perceived 30 fps video.

Flat Field Noise ­ slight differences in areas that should be identical. For example, "blotchiness" in the background behind titles. While often not objectionable to the human eye, "flat field" noise degrades compression and may be removed with the Adaptive Noise Reduction filter.

Flattening ­ a final pass applied to a compressed movie, which ensures that the movie data is laid out in a completely linear fashion. It also ensures that the sound is interleaved properly with the video.

fps ­ frames per second, a measure of the frame-rate.

Frame ­ one single still image among the many that make up a movie. A video frame is made up of two fields.

Frame Duration Data Rate Limiting ­ a method of limiting data rate by increasing frame duration to meet the desired data rate target.

Frame Rate ­ the number of frames per second of a movie.

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G.723 ­ 8:1 audio codec that works with 16-bit audio. Not available for QuickTime at the time this manual was created.

Gamma ­ the curve that describes how the middle tones of your images appear. Often incorrectly referred to as "brightness" and/or "contrast," gamma is a non-linear function. Changing the value of the gamma affects middle tones while leaving the white and black of the image alone. Gamma adjustment is used to compensate for differences between Macintosh and Windows monitors.

Generation Loss ­ image degradation that occurs each time a movie is saved with a lossy compression codec. Also occurs in each dub with analog video tape.

GSM ­ 10:1 audio codec that works with 16-bit audio. Not available cross-platform for QuickTime at the time this manual was created.

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H.263 ­ a video codec designed for low data rate video conferencing. Not freely available for QuickTime at the time this manual was published.

HTML ­ Hyper Text Markup Language. The format the World-Wide Web uses to display pages, links to other pages, etc.

http://www.terran-int.com ­ a really great site you should tell your friends about!

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IMA ­ 4:1 compression audio codec which works with 16-bit audio. Based on the standard created by the Interactive Multimedia Association.

Indeo ­ a codec developed by Intel, which allows temporal and spatial compression as well as data rate limiting for use on CD-ROM projects.

Inline ­ within the browser page, as opposed to needing to be viewed with an external application.

Interlacing Artifacts ­ horizontal lines in areas of fast movement caused by the fact that a video frame is made up of two separate fields, each 1/60th of a second apart.

Internally Data Rate Limiting Codecs ­ codecs such as Cinepak that can control the data rate of the movies they compress.

Internet ­ the coolest and biggest time-sink ever invented by humanity.

Intranet ­ large private network, often in a corporate environment.

ISDN ­ a moderately fast connection to the Internet. Theoretical throughput is between 5 KBps and 12 KBps depending on the configuration.

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KBps ­ KiloBytes per second (often referred to as "kps"), a unit of data rate measurement. Specified in this manual as "KBps" to avoid confusion with a different usage of "kps" or "kbps" by the telecommunications industry. KBps is typically used when measuring CD-ROM or broadcast video data rates.

kbps ­ kilobits per second, a unit of data rate measurement. A kilobit is 1/8th the size of a KiloByte. The term kbps is typically used when measuring web and network based video.

Keyframe ­ the complete video image which is the basis for the following delta frames.

kHz ­ kiloHertz, the number of audio samples per second. Higher sample rates yield better sound quality with better high-end response but larger files.

kps ­ ambiguous term for data rate meaning either kilobytes or kilobits per second. See "KBps" and "kbps."

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LAN ­ Local Area Network. A network that connects computers within a geographically small region, often within just one building.

LiteVDO ­ an online progressive download file format created by VDOnet to get around firewalls.

Live Action ­ video that is shot on location or in a studio which contains real-world subjects, such as people, places, etc. The term "live action video" is usually used to differentiate between real-world video and computer generated video.

Live ­ video or information that is captured, compressed, and distributed in real-time, such as "Live" news broadcasts. This is the other use of video as compared to "Store and Forward". Live video systems must use "symmetric" codecs to compress the video in real-time.

Local Area Network ­ see "LAN."

Lossless ­ compression in which no information is lost. Saving a file repeatedly with lossless compression will not affect the image quality. The Animation codec set to 100% quality is lossless.

Lossy ­ compression in which information is lost. Saving a file repeatedly with lossy compression will additionally degrade the image quality. This degradation is known as "generation loss". Cinepak is a lossy codec.

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Mean Filter ­ a filter that replaces a pixel with the average value of its surrounding pixels. Applying a mean filter effectively blurs the image.

Media ­ a term with many different meanings. In the context of this manual, it usually refers to:

1. A generic term for elements such as movies, sounds, pictures, etc. (as in multimedia)
2. Storage or transmission medium, such as tapes, diskettes, CD-R's, Zip disks, networks, etc.

Media Cleaner Wizard ­ an "expert" system that interviews the user and creates compression settings based on the user's responses.

Median Filter ­ replaces a pixel with the "most typical" value of its surroundings, while ignoring extreme values. Applying a median filter to an image tends to remove "stray pixels" and small details.

MIDI ­ Musical Instrument Digital Interface. An architecture that is used to instruct electronic instruments how to play a piece of music - think of MIDI files as "postscript" for music. QuickTime supports a data-type called QuickTime Music which is very similar to MIDI.

Modem ­ an incredibly slow way to drink from the information firehose.

Multimedia ­ a new art/communication form which combines various elements such as sound, graphics, and video. Often causes its creators to go insane and/or broke.

Multimedia Architecture ­ software including system extensions, plug-ins, servers, etc. which provide for the creation, storage and playback of synchronized multiple media types. Media Cleaner currently supports the QuickTime, RealMedia and VDOLive architectures.

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Noise ­ any part of a signal which contains unwanted randomness. In audio, noise makes the track have "hiss" or "fuzz". In video, it can appear as pixel "shimmer" or "blotchy" areas. Noise generally interferes with compression.

Noise Reduction ­ removing unwanted noise from a signal. For video this is accomplished with filters such as blur, mean, or median. Uniform noise reduction applies one filter equally to each pixel. Adaptive noise reduction applies different filters to different kinds of noise.

NTSC ­ 29.97 fps video format used by the United States and several other countries.

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Output Movie ­ compressed video ready for playback and distribution.

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PAL ­ 25 fps video format used by many European countries.

Palette ­ the list of colors which are used in an 8-bit color movie or image. There are several standard palettes, such as the Macintosh System palette. Often referred to as a "Color Lookup Table," "Color Table," or abbreviated as "CLUT."

Pixel ­ one dot in a video or still image. A typical small computer screen is 640 pixels wide and 480 pixels tall. Digital video movies are often 320 pixels wide and 240 pixels tall.

Pixelization ­ when the pixels that make up an image get exaggerated or enlarged. Makes the image look "chunky" or "jagged," and is often the result of compression artifacts.

Premiere Export Module ­ see "Export Module"

Progressive Download ­ online video files that users may watch as the files are downloaded. Progressive download files don't adjust to match the bandwidth of the user's connection like a streaming format. Currently, QuickTime is an example of a progressive download architecture.

Pulldown ­ introducing a pulldown is the process which compensates for the differences in frame rates between film and video by creating new frames. For 24 fps film to be converted to 30 fps NTSC video, a 3/2 pulldown is used which creates an extra 6 frames per second.

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QuickTime Compatible Browser ­ a browser (such as Netscape Navigator 3.0) that supports the inline viewing of QuickTime movies.

QuickTime Music ­ track that is very similar to MIDI. Allows music to be stored as instructions rather than digitized sounds, and then played back with defined instruments within QuickTime. QuickTime Music tracks are much smaller than digitized versions of the same music. Often referred to as MIDI even though it technically isn't.

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RealAudio ­ an online audio format created by Progressive Networks.

RealMedia ­ a progressive download, server-optional, online multimedia architecture created by Progressive Networks.

RealVideo ­ the first version of RealMedia, which only supports video and audio.

Recompression Data Rate Limiting ­ a method of limiting the data rate of a movie by recompressing frames that are larger than desired.

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Sample ­ the measurement of a signal level at one specific instant in time.

Sample Size ­ the accuracy with which a sound sample is recorded. Generally, audio sample size is 8-bit or 16-bit. The latter is more accurate and provides more dynamic range, but takes up more storage space.

Sample Rate ­ the number of samples per second used for audio. A higher sample rate yields higher quality audio that is larger than lower sample rates. For CD-ROM movies, the two most common sample rates are 11.025 kHz and 22.050 kHz.

Server ­ term which can either mean hardware or software:

1. Hardware ­ a computer that other computers connect to for the purpose of retrieving information. In this manual, generally used to mean the computer that hosts your WWW page.
2. Software ­ a software program that runs on your WWW server to support online video (such as the "VDOLive server" or the "RealMedia server").
Server-Based ­ technologies that require a server, such as VDOLive.

Serverless ­ technologies that don't require a server, such as QuickTime.

Server-Optional ­ technologies that don't require a server, but may benefit from them, such as RealMedia.

Settings Group ­ a name for all of the parameters in the Settings window. Also commonly referred to as simply "settings". Settings groups can be saved, modified, and deleted.

Source Movie ­ the original movie to be compressed.

Stray Pixel Noise ­ noise that appears as random pixels which are significantly different from the surrounding pixels. Occasionally caused by low-quality sources (such as VHS), multiple duplications, low light compensation, etc. May be removed with the Adaptive Noise Reduction filter.

Spatial Compression ­ a compression method that removes redundant data within any given image. For example, a field of blue in a picture would be stored as one large blue area rather than many individual blue pixels.

Spikes ­ See "Data Rate Spikes"

Sprites ­ QuickTime track that is made up of small graphic elements (sprites) which have position and time information associated with them. A bouncing ball is a good example of a sprite track ­ only the ball and its location are stored at any given time instead of a series of bitmaps that describe each whole frame.

Static Mask­ (previously the "Talking Heads filter") a Media Cleaner feature which composites defined areas of an image across frames to improve temporal compression.

Status Bar ­ the floating bar with the Start, Suspend and Resume buttons on it. The Status Bar displays the status of the current compression.

Store and Forward ­ video that is not broadcast "live" when it is filmed, but is compressed and made available on a server for people to watch when they wish. Also called "on demand" video. See "Live" for the other common use of video.

Streaming ­ refers to data that is transferred in real-time. In this manual, streaming is used to refer to technologies like VDOLive that match the bandwidth of the video signal to the viewer's connection, so that the video is always seen in real-time.

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T1 ­ a fast network connection. Theoretical limit is 150 KBps, but the realities of the Internet usually cut the throughput down dramatically.

Text Tracks ­ QuickTime track that is made up of text, positioning, and time information. It is often used for subtitles, etc.

"Talking Heads" Filter ­ Movie Cleaner name for the "Static Mask".

Target Machine ­ the typical/minimal configuration (of computer hardware and software) on which a movie will be viewed.

Telecine ­ the film-to-video conversion machine that introduces the 3/2 pulldown necessary to compensate for the differences in frame rates between film and video.

Temporal Compression ­ compression of movies by elimination of duplicate storage of similar areas across sequential images. For example, if several frames in a row have almost identical details, the details need only be stored once.

Terran ­ of, or relating to, the planet Earth (as in "Terra Firma").

Toggle ­ the little triangle shaped buttons which rotate to reveal more information. Similar to the little triangles in the Finder that let you view the contents of a folder without first opening it. Clicking once on them reveals more information; clicking again hides the extra information.

Tracks ­ the separate media types that make up a movie. Most movies include a video track and an audio track. In some multimedia architectures such as QuickTime, there are also text tracks, sprite tracks, music tracks, and more unusual track types.

Transcode ­ changing a file from one format to another without having to recompress the data. Often refers to changing Video for Windows files into QuickTime movies, and vice versa. Similarities in the file structure and codecs of the two architectures allow some files to be transcoded without the video being recompressed.

True Streaming ­ see "Streaming"

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Upload ­ to move a file from your computer to your server.

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Variable Frame Length Movie ­ a movie that contains frames that are not all of equal duration. Supported by QuickTime, but not Video for Windows.

VDOLive ­ a true streaming, server-based online video architecture created by VDOnet.

Vertical edge blanking ­ see "Edge Blanking"

Video Fades ­ feature that starts a movie with a solid color (such as black) and blends into the beginning of the movie over time. This effect may be reversed for the end of a movie.

Volume ­

1. A hard disk drive, floppy diskette, CD-ROM, or other storage device or piece of storage media.
2. The level of your audio track.


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WAN ­ Wide Area Network. A network connecting a large area, usually more than one building.

Web-Motion ­ a plug-in for Movie Cleaner that helped users create web-ready video. Now integrated into Media Cleaner Pro.

Web-Ready ­ a term used to refer to movies that are optimized for distribution on the World Wide Web. Movies must be flattened for cross-platform playback, fast start, and not contain unsupported data-types. Web-ready movies should also have a low enough data rate that most target users can watch them without unreasonable waiting.

Wide Area Network ­ see "WAN"

Windows Machine ­ an IBM compatible computer running Microsoft's Windows operating system.

Wizard ­ a generic term for a system that helps users configure computer software or settings. See "Media Cleaner Wizard."

WWW ­ World-Wide Web. The graphical subset of the Internet.

WYSIWYG ­ What You See Is What You Get. A very silly looking acronym meaning what you see on your computer screen is actually what you will get in your final output. Rarely true.

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