Appendix

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Appendix

glossary

[a] [b] [c] [d] [e] [f] [g] [h] [i] [j] [k] [l] [m] [n] [o] [p] [q] [r] [s] [t] [u] [v] [w] [X] [Y] [Z]

a

aac: advanced audio coding. standardized, lossy compression and encoding scheme for digital audio. aac is promoted as the successor to the mp3 format by mp3’s creator, fraunhofer iis. depending on the encoder used, aac generally achieves better sound quality than mp3 at the same bitrate, particularly below 192 kbit/s. aac’s most famous usage is as the default audio format of apple's iphone, ipod, itunes, and the format used for all itunes store audio (with extensions for proprietary digital rights management (drm) where used). aac is also the standard audio format for sony’s playstation 3, the mpeg-4 video standard, and he-aac is part of digital radio standards like dab+ and digital radio mondiale.
adpcm: adaptive differential pulse-code modulation. a technique for converting sound or analog information to binary information (a string of 0's and 1's) by taking frequent samples of the sound and expressing the value of the sampled sound modulation in binary terms. adpcm is used to send sound on fiber-optic long-distance lines as well as to store sound along with text, images, and code on a cd-rom. this method of encoding sound data files takes up less storage space than the regular pcm format used by wav and aiff files--and cd audio for that matter. adpcm comes in more than one flavor: ima's adpcm, for example, is used on the sony mini disc to cram more data onto a smaller platter; microsoft adpcm is used as part of windows 95's canon of audio codecs.
amr: adaptive multi-rate. an audio data compression scheme optimized for speech coding. amr was adopted as the standard speech codec by 3gpp in october 1998 and is now widely used in gsm. it uses link adaptation to select from one of eight different bit rates based on link conditions. amr is also a file format for storing spoken audio using the amr codec. many modern mobile telephone handsets will allow you to store short recordings in the amr format, and some commercial programs exist to convert between this and other formats such as mp3, although it should be remembered that amr is a speech format and is unlikely to give ideal results for other audio.
artifacts: unusual or unwanted video distortion. examples of artifacts include flicker, jitter, degradation of resolution, and aspect ratio abnormalities.
aspect ratio: the aspect ratio is the relationship of screen width to height. standard broadcast tv has a ratio of 4 to 3. widescreen commonly has a ratio of 16 to 9 (although 1.85:1 and 2.11:1 are also used). to show widescreen movies on a standard tv screen, either letterbox (with black bars above and below the image) or 'pan and scan' (which crops the movie to fit the screen) are common techniques.
audio feedback: a special kind of feedback which occurs when a sound loop exists between an audio input (for example, a microphone or guitar pickup) and an audio output (for example, a loudspeaker). in this example, a signal received by the microphone is amplified and passed out of the loudspeaker. the sound from the loudspeaker can then be received by the microphone again, amplified further, and then passed out through the loudspeaker again. this is a good example of positive feedback. the frequency of the resulting sound is determined by resonant frequencies in the microphone, amplifier, and loudspeaker, the acoustics of the room, the directional pick-up and emission patterns of the microphone and loudspeaker, and the distance between them.
avi: audio video interleave. the original microsoft file format for microsoft's video for windows standard. it is an audio video standard designed by microsoft and is apparently proprietary and microsoft windows specific. it is a format developed for storing video and audio information. files in this format have an .avi extension. however, video for windows does not require any special hardware, making it the lowest common denominator for multimedia applications.

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b

b-frames: bidirectional frames - frames used in mpeg-4 format that are compressed based on the frames before and after them. have the greatest compression ratio among all frame types. see b-vops codec settings section for more detail.
bd: blu-ray disc. a next-generation optical disc format meant for storage of high-definition video and high-density data. the blu-ray standard was jointly developed by a group of leading consumer electronics and pc companies called the blu-ray disc association (bda), led by sony and philips. a single-layer blu-ray disc (bd) can fit 23.3, 25, or 27 gb; this is enough for approximately four hours of high-definition video with audio. a dual-layer bd can fit 46.6, 50, or 54 gb, enough for approximately eight hours of hd video. capacities of 100 gb and 200 gb, using four and eight layers respectively, are currently being researched; tdk has already announced a four-layer 100 gb disc.
bandwidth: a network's capacity for transferring an amount of data in a given time.
bidirectional frames: see b-frames.
bit rate: the number of bits transferred per second.
brightness: the value of a pixel along the black-white axis.
b-vops: an option that allows the codec algorithm to use so called bidirectional frames that are much smaller in size than usual frames and are predicted based on the frames before and after them.

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c

capture

to record audio, video, or still images as digital data in a file.

capture device

hardware that transfers audio and video from an external source, such as a vcr or camcorder, to a computer.

chapters

dvd discs can be split up into titles, and then further into chapters. for example, on a disc with multiple sporting events, each event may be designated as a separate title. each period in the individual sporting event or title may be designated a chapter.

chroma motion

an algorithm that lets the codec detect motion in an advanced way and calculate the possibility to additionally compress the output file without the quality loss.

chroma optimizer

an algorithm used to produce a better impression of objects edges by reducing the noise around them.

chromaticity

chromaticity is an objective specification of the quality of a color regardless of its luminance, that is, as determined by its saturation (or colorfulness) and hue.

clip

1. the audio, video, or still images within dvd discs. clips are stored in collections.

2. the audio, video, or still images within avs video editor.

clip creation

the process of detecting and splitting video content into separate clips.

codec

an abbreviation for compressor/decompressor. software or hardware used to compress and decompress digital media.

color depth

color depth or bit depth, is a computer graphics term describing the number of bits used to represent the color of a single pixel in a bitmapped image or video frame buffer. this concept is also known as bits per pixel (bpp), particularly when specified along with the number of bits used. higher color depth gives a broader range of distinct colors.

1-bit monochrome - typically the two colors used for a binary image are black and white, though any two colors can be used
8-bit greyscale - greyscale images have many shades of grey in between in comparison with one-bit black-and-white images
8-bit color - the maximum number of colors that can be displayed at any one time is 256
15/16-bit color (highcolor) - it allows 32,768/ 65,536 possible colors for each pixel
24-bit color (truecolor) - it means at least 256 shades of red, green, and blue, for a total of at least 16,777,216 color variations
30/36/48-bit color (deepcolor) - anything superior to truecolor, typically over a billion colors; the xvYcc, srgb, and Ycbcr color spaces can be used with deepcolor systems

color model

a color model is an abstract mathematical model describing the way colors can be represented as sequences of numbers, typically as three or four values or color components. when this model is associated with a precise description of how the components are to be interpreted (viewing conditions, etc.), the resulting set of colors is called color space.

color space

any specific method for associating tristimulus values with each color.

cmYk - cyan (c), magenta (m), yellow (Y), and black (k) - used in the printing process
srgb or standard rgb - red, green, blue - created cooperatively by hewlett-packard and microsoft corporation for use on the internet
adobe rgb - developed by adobe systems in 1998, designed to encompass most of the colors achievable on cmYk color printers, but by using rgb primary colors on a computer display
hsv, also known as hsb - hue, satutarion, value/ brightness - lightness of a pure color is equal to the lightness of a medium grey
hsl, also known as hls, hsi, or tsd - hue, saturation, lightness/ luminance - brightness of a pure color is equal to the brightness of white
Yiq, Yuv, Ydbdr - Yiq was formerly used in ntsc, Yuv in pal, Ydbdr in secam
Ypbpr, Ycbcr - Ypbpr is a scaled version of Yuv. it is most commonly seen in its digital form, Ycbcr, used widely in video and image compression schemes such as mpeg and jpeg
xvYcc - a new international digital video color space standard
cie 1931 XYZ - the first attempt to produce a color space based on measurements of human color perception and it is the basis for almost all other color spaces
cieluv - a modification of "cie 1931 XYZ" to display color differences more conveniently, especially useful for additive mixtures of lights, due to its linear addition properties
cielab - designed to produce a color space that is more perceptually linear than other color spaces (i.e. a change of the same amount in a color value should produce a change of about the same visual importance)
cieuvw - measurements over a larger field of view than the "cie 1931 XYZ" color space which produces slightly different results

color wheel

the color wheel or color circle is the basic tool for combining colors. the color wheel is designed so that virtually any colors you pick from it will look good together. over the years, many variations of the basic design have been made, but the most common version is a wheel of 12 colors based on the rYb (red, yellow, blue) color model.

compression

a process for removing redundant data from a digital media file or stream to reduce its size or the bandwidth used.

content

audio, video, images, text, or any other information that is contained in a digital media file or stream.

css

"content scramble system". the official dvd-video digital encryption scheme.

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d

data rate: the speed of a data transfer process, usually expressed in kilobytes (thousands of bytes) per second. see also bit rate.
dc bias (dc offset): an offsetting of a signal from zero. the term originated in electronics, where it refers to a direct current voltage, but the concept has been extended to any representation of a waveform. dc offset is the mean amplitude of the waveform; if the mean amplitude is zero, there is no dc offset. dc offset is usually undesirable. for example, in audio processing, a sound that has dc offset will not be at its loudest possible volume when normalized (because the offset consumes headroom), and this problem can possibly extend to the mix as a whole, since a sound with dc offset and a sound without dc offset will have dc offset when mixed. it may also cause other artifacts depending on what is being done with the signal. dc offset can be reduced in real-time by a one-pole one-zero high-pass filter. when one already has the entire waveform, subtracting the mean amplitude from each sample will remove the offset if the offset is constant throughout the waveform. otherwise, the high-pass filter should be used.
decode: the process of converting the data on a dvd into the video image on the screen.
decompress: convert video and audio data from a compressed form back into its original form.
delta frames: see p-frames.
digital video (dv): video images and sound stored in a digital format.
to download: to transfer a file over a network in response to a request from the device that receives the data. downloaded content is kept on the receiving device for playback on demand. in contrast, streamed content is played as it is delivered.
dvd: digital versatile disc - an optical disc used to store information that has rather a large capacity as compared with usual cd's. needs special dvd drive to read such a disc.

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e

encode: convert video or audio into a compressed format.

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f

fft: fast fourier transform. an efficient algorithm to compute the discrete fourier transform (dft) and its inverse. ffts are of great importance to a wide variety of applications, from digital signal processing and solving partial differential equations to algorithms for quick multiplication of large integers. the discrete fourier transform, occasionally called the finite fourier transform, is a transform for fourier analysis of finite-domain discrete-time signals. as with most fourier analyses, it expresses an input function in terms of a sum of sinusoidal components by determining the amplitude and phase of each component. however, the dft is distinguished by the fact that its input function is discrete and finite: the input to the dft is a finite sequence of real or complex numbers, which makes the dft ideal for processing information stored in computers. in particular, the dft is widely employed in signal processing and related fields to analyze the frequencies contained in a sampled signal, to solve partial differential equations, and to perform other operations such as convolutions. the dft can be computed efficiently in practice using a fast fourier transform algorithm. since fft algorithms are so commonly employed to compute the dft, the two terms are often used interchangeably in colloquial settings, although there is a clear distinction: "dft" refers to a mathematical transformation, regardless of how it is computed, while "fft" refers to any one of several efficient algorithms for the dft. this distinction is further blurred, however, by the synonym "finite fourier transform" for the dft, which apparently predates the term "fast fourier transform" but has the same initialism.
frame: one of many sequential images that make up video.
frame drop ratio: the percentage of frames that don't have any important information and thus can be dropped.
frame rate: the number of video frames displayed per second. higher frame rates generally produce smoother movement in the picture.
frame size: the number of pixels that form the video image (horizontally/vertically).
full motion video: content that shows 30 (interlaced) or 24 (film content) frames per second.

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g

gain: a measure of the ability of a circuit to increase the amplitude or power of a signal. it is usually defined as the mean ratio of the signal output of a system to the signal input of the same system. it may also be defined as the decimal logarithm of the same ratio.; thus, the term gain on its own is ambiguous. for example, 'a gain of five' may imply that either the voltage or the power is increased by a factor of five.
global motion compensation: an algorithm that helps while coding the objects that only change their size or place in the picture but keep static.
gsm: an open file format designed for telephony use in europe, gsm is a very practical format for telephone quality voice. it makes a good compromise between file size and quality. note that wav files can also be encoded with the gsm codec.

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h

hd dvd: high-definition digital versatile disc or high-density digital versatile disc is a high-density optical disc format designed for the storage of data and high-definition video. hd dvd-rom has a single-layer capacity of 15 gb, a dual-layer capacity of 30 gb, and a 51 gb single-sided triple-layer disc (which uses slightly bigger 17 gb layers), approved in september 2007 by the dvd forum. however, the 51 gb spec is only a preliminary spec and compatibility with existing hardware is unknown at this time. hd dvd-r and hd dvd-rw has a single-layer capacity of 15 gb, a dual-layer capacity of 30 gb.
hdd: hard disk drive.
highlight (photography): the brightest areas in a picture, which often occur as a result of an incorrect exposure when initially photographing or scanning to a digital image. increasing an exposure increases the intensity of light, and increasing it too far will cause the lightest areas, such as the sky, or light sources, to clip.
to highlight: activate or focus menu or selection. when the cursor is moved over an option on a dvd menu, that menu often changes color. it is then "highlighted".
hue: in painting color theory, a hue refers to a pure color — one without tone, tint or shade. usually, colors with the same hue are distinguished with adjectives referring to their lightness and/or chroma, such as with "light blue", "pastel blue", "vivid blue". exceptions include brown, which is a dark orange, and pink, a light red with reduced chroma.

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i

i-frames: also called intraframes or keyframes - frames with a very small compression ratio used to form the base of the video picture. see b-vops codec settings section for more detail.
import: the process of bringing existing digital audio, video, and still image files into avs video converter or avs video editor programs.
indexed color: in computing, indexed color is a technique to manage digital images' colors in a limited fashion, in order to save computer's memory and file storage, while speeding up display refresh and telecom transfers. when an image is encoded this way, the color information is not directly carried by the image pixel data, but it is stored into a separate piece of data called a palette: an array of color elements, in which every element, a color, is indexed by its position within the array. this way, each pixel does not contain the full information to represent its color, but only its index into the palette. this technique is sometimes referred as pseudocolor or indirect color, as colors are addressed indirectly.
interframes: see p-frames.
intraframes: see i-frames.

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j

jitter: the smoothness of frame delivery over time.

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k

keyframes: see i-frames.

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l

letterboxing: the practice of transferring widescreen films to video formats while preserving the original aspect ratio.
lfo: low-frequency oscillation. an audio signal usually below 20 hz which creates a pulsating rhythm rather than an audible tone. lfo predominantly refers to an audio technique specifically used in the production of electronic music. the abbreviation is also very often used to refer to low-frequency oscillators themselves, which produce the effects explored in this article.
lumimasking: an algorithm used to apply more compression to very dark and very bright areas where it cannot be easily noticed by the human eye.

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m

m4a: m4a files are actually the audio layer of (non-video) mpeg-4 movies. m4a is slated to become the new standard for audio file compression. this format is also known as apple lossless, apple lossless encoder, or ale. it is a new codec designed to provide lossless encoding in less storage space.
matte (usually used in plural - mattes): the masked-off areas above and below the picture area, used to maintain original aspect ratio when viewing video on the screen with a different aspect ratio.
max consecutive b-vops: maximum number of sequential bidirectional frames in the video stream.
max key interval: maximum number of delta frames (interframes) between two keyframes (intraframes).
motion search type: an algorithm that allows the codec to search for the motions in the movie and better compress them with a higher quality.
mov: a file extension for quicktime video clip. quicktime is a video and animation system developed by apple computer. quicktime is built into the macintosh operating system and is used by most mac applications that include video or animation. pcs can also run files in quicktime format, but they require a special quicktime driver. quicktime supports most encoding formats, including cinepak, jpeg, and mpeg. quicktime is competing with a number of other standards, including avi and activemovie. for more information see the apple site and their support page.
movie file: the file created by combining the audio, video, and still images contained in your project.
mp+: a musepack music format, a popular high quality lossy compression that offers higher audio quality than mp3. nowadays musepack audio files generally have the extension .mpc, but lots of files with the extension .mp+ still float around file sharing networks. musepack is based on the mpeg-1 audio layer 2 standard (mp2), but includes many improvements. it is believed by audiophiles to be one of the highest quality lossy compressions available for music.
mp2: mpeg-1 audio layer ii, sometimes musicam. an audio codec defined by iso/iec 11172-3. an extension exists: mpeg-2 layer ii and is defined in iso/iec 13818-3. the file extension for files containing such audio data is usually .mp2. while it has largely been superseded by mp3 for pc and internet applications, it remains a dominant standard for audio broadcasting as part of the dab digital radio and dvb digital television standards. it is also used internally within the radio industry, for example in npr's prss content depot programming distribution system.
mp3: mpeg-1 audio layer 3. an audio encoding format. it uses a lossy compression algorithm that is designed to greatly reduce the amount of data required to represent the audio recording, yet still sound like a faithful reproduction of the original uncompressed audio to most listeners. it was invented by a team of european engineers at philips, ccett (centre commun d'etudes de television et telecommunications), irt and fraunhofer society, who worked in the framework of the eureka 147 dab digital radio research program, and it became an iso/iec standard in 1991. mp3 is an audio-specific format. the compression removes certain parts of sound that are outside the normal human hearing range so cannot be heard by the listener. it provides a representation of pulse-code modulation — encoded audio in much less space than straightforward methods, by using psychoacoustic models to discard components less audible to human hearing, and recording the remaining information in an efficient manner. using mp3-compression pc-users were able to compress an ordinary music-cd to one tenth of its original size - thus 12 hours of music could be stored on a recordable cd that on the other hand could be played by a mp3-cd-player or an ordinary pc.
mpeg: moving picture experts group. gives excellent compression with little loss in quality of the video. mpeg supports three types of data - video, audio and streaming. there are a number of standards: among them there are two flavors of mpeg available today. mpeg-1 was designed to provide vhs video quality and cd audio quality at a combined data rate of 150 kilobytes per second. mpeg-1 is displayed at 30 frames per second in a frame that is 352x240 (horizontal x vertical) pixels in size. this allows relatively high quality video images to be stored in relatively small file sizes for playback across computer networks or cd-rom delivery. mpeg-2 is the other side of the compression coin. it is a broadcast standard specifying a playback size of 720 x 480 pixels at 60 fields per second. data rates can range from 2 to 10 megabits per second. this means large file sizes and data rates that require specialized hardware for playback. mpeg-2 is one of the core compression technologies for dvd. see the mpeg site for more information.
mpeg-4: iso/iec open standard for video encoding developed by mpeg (moving picture experts group). it is characterized by a small output video file size and quite good picture quality even when a relatively low bit rate is used. the most known resulting output when you use mpeg-4 format for compression is the avi file type which is commonly used in home video. it is coded with Xvid, divX, 3ivx, nero digital and other video codecs.
msc: devices that represent usb mass storage device class (msc or ums) are seen as a removable drive in the system and some of them as a fixed drive.
mtp: devices representing usb mtp device class use media transfer protocol (mtp) supported by microsoft windows media player 10 and 11.
multimedia: any format that contains more than one media, such as text, still images, sound, animation, and video.

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n

navigation: accessing the features of a dvd-video disc.
ntsc: national television systems committee. a committee of the electronic industries association that prepared the standards for commercial television broadcasting in the united states, canada, japan, and parts of central and south america. the ntsc format has 525 scan lines (rows) of resolution at frame rate of thirty frames per second.

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o

ogg: an open standard for a free container format for digital multimedia, unrestricted by software patents and designed for efficient streaming and manipulation. the development of the ogg standard began in 1993, then known as "squish". it was designed as a substitute for mp3 and wma and by now it is almost as popular and well known as mp3. above all, the algorithm is still being developed what is mainly due to its flexibility. although the sound-quality gets better with every further development the files are backwards compatible and can be played with older players as well. like mp3 ogg offers encoding at variable bitrates. using this compression parts of the song are encoded with a higher compression than others what depends on the source. most times, this compression goes along with squishy noises or even small interruptions. ogg is also one of the very few formats that support multi-channel compression. surround-files could theoretically be compressed with more than two channels. ogg is, like it's predecessors, streamable and although the used player has to support this feature, it's one of many good reasons for ogg.
output file: the file that is a result of conversion of a source file.

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p

p-frames: delta frames or interframes - frames used in mpeg-4 format to increase the compression ratio. a row of p-frames is placed between two i-frames - thus the name interframes was given. see b-vops codec settings section for more detail.
pal: phase alteration line. this standard is used for commercial broadcasting in most of europe, australia, and parts of central and south america. pal format displays at 625 scan lines (rows) of resolution at frame rate of 25 frames per second.
pillar boxing: the practice of transferring films having aspect ratio of 1.33:1 to wide screens while preserving the original aspect ratio.
pitch: the perceived fundamental frequency of a sound. while the actual fundamental frequency can be precisely determined through physical measurement, it may differ from the perceived pitch because of overtones, or partials, in the sound. the human auditory perception system may also have trouble distinguishing frequency differences between notes under certain circumstances. according to ansi acoustical terminology, it is the auditory attribute of sound according to which sounds can be ordered on a scale from low to high.
pixel: picture cell. this is the smallest independent unit of a digital image; similar to each dot on your monitor.
pixel depth: the number of bits of color information per pixel.
player: a program or device that displays multimedia content, typically animated images, video, and audio.
project file: the file created when you save the results of adding various clips to the workspace when you work with avs video editor. this file is saved with an .vep4 extension.

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q

qt: apple quick time format for audio/video data.
quantizer: detail removal factor (drf), or the degree of picture blur due to details reduction. used to allow picture compression.
quantizer offset: the offset used to calculate frames quantizer.
quantizer ratio: the ratio used to calculate frames quantizer.

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r

to record: to capture audio, video, or still images as digital data in a file.
regional coding: region code - the software protection used on dvd discs to prevent unauthorized playback of the discs made in one country to be played in another country.; most dvd-rom drives let you change the region code a few times, usually between 0 and 5. once a drive has reached the limit it can't be changed again unless the vendor or manufacturer resets the drive. this limitation cannot be overridden.; there are 7 regions: (1) canada, u.s., us territories; (2) europe, japan, south africa, middle east (including egypt); (3) southeast asia, east asia (including hong kong); (4) australia, new Zealand, pacific islands, central america, mexico, south america, caribbean; (5) former soviet union, indian subcontinent, africa (also north korea, mongolia); (6) china and (7) transcontinental - used for watching dvd movies onboard the planes, ships and so forth.
resolution: see frame size
rgb model: color spectrum represented by mixing red, green, and blue (rgb) colored light in various proportions and intensities.
rm: real media streaming format for audio/video data. realmedia provides one of the oldest and most widespread (85% of all web-accessing computers have realplayer installed) web delivery formats. the realmedia files (.rm) can be viewed using realplayer 3 and above. for more information see the realnetworks site and their user information site.
root-mean-square: abbreviated rms or rms, also known as the quadratic mean, is a statistical measure of the magnitude of a varying quantity. it is especially useful when variates are positive and negative, e.g. waves. it can be calculated for a series of discrete values or for a continuously varying function. the name comes from the fact that it is the square root of the mean of the squares of the values.

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s

saturation: that is the strength (purity) of colors. saturation represents the amount of grey in proportion to the hue, measured as a percentage from -100 (grey) to 100 (fully saturated).
source: audio and video content that can be captured and encoded from devices installed on your computer or from a file.
split: the process of dividing an audio or video clip into two parts.
still image: a graphic file, such as a .bmp, .gif, or .jpg.
storyboard: a view of the workspace that focuses on the sequencing of your clips (used in avs video editor).
subtitle: subtitles show the words being spoken on top of video content. they are often used for language translations.
swf: macromedia/adobe flash format, used to create video files that can be easily placed to your home page as they use not too much space and are supported by most browsers (in case the necessary plugin is installed). see the adobe web site for more info on this format.

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t

timeline: 1. the area of the user interface that shows the timing and arrangement of files that make up a media file.; 2. a view of the workspace that focuses on the timing of your clips.
titles: video programs can be split up into titles, and then further into chapters. a good example of titles is when a dvd contains a movie (one title), the trailer for the movie (a second title), and biographies of the actors (a third title), all on the same disc.
tone, tint, shade: these terms are often used incorrectly, although they describe fairly simple color concepts. if a color is made lighter by adding white to a pure hue, the result is called a tint. if black is added, the darker version is called a shade. and if gray is added, the result is a different tone. so midtones are areas of an image, which consist of close to 50% grey (or 50% color).
transition: the method of smoothly moving from one video clip or photo to another.
trim: hiding parts of a file or clip without deleting them from the original source. files and clips can be trimmed by adjusting the start or end trim points. used in avs video editor.
tristimulus values: the human eye has receptors for short, middle, and long wavelengths. thus in principle, three parameters describe a color sensation. the tristimulus values of a color are the amounts of three primary colors in a three-component additive color model needed to match that test color. any specific method for associating tristimulus values with each color is called a color space.

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u

ums: devices that represent usb mass storage device class (msc or ums) are seen as a removable drive in the system and some of them as a fixed drive.

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v

vbr: variable bit rate. this allows dvd compression methods to use more or less compression according to the complexity of the picture.
vhq mode: an algorithm that decides which format will be used to store motion vectors thus reducing the file size.
vob: dvd video movie file. dvd is the new generation of optical disc storage technology. dvd is essentially a bigger, faster cd that can hold cinema-like video, better-than-cd audio, still photos, and computer data. dvd aims to encompass home entertainment, computers, and business information with a single digital format. it has replaced laserdisc, is well on the way to replacing videotape and video game cartridges, and could eventually replace audio cd and cd-rom. dvd has widespread support from all major electronics companies, all major computer hardware companies, and all major movie and music studios.
voX: dialogic adpcm. an open file format optimized for storing digitized voice data at a low sampling rate. voX files are most commonly found in telephony applications, as well as an occasional arcade redemption game. similar to other adpcm formats, it compresses to 4-bits. unlike a wav file, a voX file does not contain a header to specify the encoding format or the sampling rate, so this information must be known in order to play the file. if not known, it is normally assumed that a voX file is encoded with dialogic adpcm at a sampling rate of 8000hz. it is possible that a voX file may be encoded in a format other than dialogic adpcm, but this is not common.

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w

wav/wave: short for waveform audio format, a microsoft and ibm audio file format standard for storing audio on pcs. it is a variant of the riff bitstream format method for storing data in "chunks", and thus also close to the iff and the aiff format used on amiga and macintosh computers, respectively. it is the main format used on windows systems for raw audio.
warm and cold colors: the color wheel can be divided into warm and cold colors. warm colors are vivid and energetic, and tend to advance in space. cold colors give an impression of calm, and create a soothing impression. white, black and gray are considered to be neutral.
white point: it is a set of tristimulus values or chromaticity coordinates that serve to define the color "white" in image capture, encoding, or reproduction. depending on the application, different definitions of white are needed to give acceptable results. for example, photographs taken indoors may be lit by incandescent lights, which are relatively orange compared to daylight. defining "white" as daylight will give unacceptable results when attempting to color correct a photograph taken with incandescent lighting.
widescreen: most tvs display in 4:3 ratio. widescreen display shows you the same ratio that is used for movies, which is frequently 16:9. if the title is being shown on a widescreen tv it can be shown in its original aspect ratio without the display of the black bars above and below the image.
windows media file: a file containing audio, video, or script data that is stored in windows media format. depending on their content and purpose, windows media files use a variety of file name extensions, such as: .wma, .wme, .wms, .wmv, .wmx, .wmz, or .wvx.
wma: windows media audio, an audio data compression technology developed by microsoft. the name can be used to refer to its audio file format or its audio codecs. it is a proprietary technology which forms part of the windows media framework. wma consists of four distinct codecs. the original wma codec, known simply as wma, was conceived as a competitor to the popular mp3 and realaudio codecs. it is the second most popular audio codec after mp3, based on the number of supported devices researched by jupiter research. wma pro, a newer and more advanced codec, supports multichannel and high resolution audio. a lossless codec, wma lossless, compresses audio data without loss of audio fidelity. and wma voice, targeted at voice content, applies compression using a range of low bit rates.
wmv: windows media video, microsoft's new standard for audio and video which is closely tied with the windows operating system. the player is able to play windows media video (.wmv) and advanced streaming format (.asf) files, and also other formats such as quicktime, avi, mpeg and mp3. see the windows media site for more information.
workspace: the area of avs video editor in which you create your movies. it consists of two views: storyboard and timeline, which act as a container for work in progress.

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