525/60 An abbreviation for NTSC video derived from the number of scan lines (525) and the refer- ence scanning frequency (60 Hz).
625/50 An abbreviation for PAL video derived from the number of scan lines (625) and the refer- ence scanning frequency (50 Hz).
A
AAC (Advanced Audio Codec) An audio-encod- ing standard for MPEG-2 that is not backward-com- patible with MPEG-1 audio.
AC-3 (See also Dolby Digital) Properly, the orig- inal name for a Dolby digital audio encoding algo- rithm used for many different channel formats from Mono to 5.1. Commonly misreferenced as Dolby 5.1, this format also includes a six-channel theatrical sound format (using one channel each for front left, center, and right, left surround, right surround, and a subwoofer), AC-3 was subsequently adapted for home use and has now become one of the most com- mon sound formats for DVD. It now goes by its proper name of Dolby Digital. AC-3 is the successor to Dolby’s AC-1 and AC-2 audio-coding techniques.
Amaray Case The “standard” packaging for a DVD, as designated by the VSDA (Video Software Dealers Association).
Amplifier A device that increases the sound level of an audio signal so it can be played through speak- ers.
Analog Digital video or audio information is stored in numbers; analog uses a continuously vari- able signal of any kind.
Analog Controls Controls that move in a smooth progression, as opposed to the discrete steps that characterize digital. Unlike digital controls, analog controls must be reset every time.
Anamorphic In DVD, used to indicate widescreen video content (typically 16 ⫻ 9) that has been squeezed into a 4 ⫻3 visual space for encoding. In film, an anamorphic movie is a widescreen movie in which the image is squeezed to fit on a standard 35 mm film negative.
Anamorphic Mastering Anamorphically mas- tered titles can play widescreen (16 ⫻9) or standard TV (4 ⫻3) formats with black letterbox bars on the top and bottom of the screen. The instructions about which version to use with which television set are imbedded in the disc’s MPEG data stream. For DVD, the image can be digitally unsqueezed.
Angle A specific view of a scene, sometimes recorded from a certain camera position, sometimes just a different edited cut. DVD players allow view- ers to choose from as many as nine different camera angles on titles offering multiple angles, but few titles really take advantage of this standard DVD player feature.
Angle Menu An optional DVD Menu used to select the video angle number.
Artifact A flaw in the MPEG encoded video image that mars the picture quality, and was not pres- ent in the original material.
Asset list A complete list of the various audio, video, graphic, text, and subpicture elements included in a DVD title.
Assets The audio, video, graphic, text, and sub- picture elements included in a DVD title.
Aspect Ratio The ratio between the width and height of a screen. The aspect ratio for standard TV is 4x3; widescreen TV is typically 16 ⫻9. This is sometimes also show, using the colon, as in 4:3, 16:9.
Authoring The generally-used name for preparing a DVD-Video disc for replication, or for DVD-R burning. The physical process of assembling assets and navigation into a playable DVD.
Audio Menu An optional DVD Menu used to select the audio stream.
Audio Stream Number The consecutive numbers assigned to the audio streams for a title in a VTS.
These numbers range from 0 to 7 in the order described in the VTS manager area. For menus, the number of audio streams is limited to 0 or 1.
Audio_TS The UDF file name used for a DVD- Audio directory on disc volume. On SD DVD-Video- only discs, this directory is empty.
B
B-Frame (or B-Picture) One of three picture types used in MPEG video. An MPEG “Bi-direc- tionally Predictive” frame. Compressed both spa- tially and temporally, and with some regard for motion estimation, a B frame uses information from its neighboring I- and P-frames to properly recon- struct the video frame at that instant. An MPEG Chapter may not be placed on this frame.
Bandwidth The amount of information that can be carried by a circuit or a signal. The larger the band- width, the sharper and more complex the image can be. In digital technologies, bandwidth is referred to as “data rate.”
Bit Rate The rate at which digital information is presented or encoded. Since there is room for only so
many bits on a DVD, the bit rate can vary. The rate is kept lower for simpler sequences so that extra space will be available for more complex ones.
Bitmap A format for storing still graphic images. In DVDs, bitmaps are used for menus and subpicture overlays.
Blocking A visible artifact of digital com- pression in which blocky rectangular areas appear in the picture due to an encode rate insuf- ficient to properly capture the picture details.
Burst Cutting Area A circular section near the center of a DVD disc where ID codes and manufacturing information can be inscribed in bar code format.
Button This is a rectangular area in the sub- picture display area highlighted by the Highlight Information (HLI) that is used to define the active area on a menu associated with a specific action.
Button Number The consecutive numbers assigned to every button on a menu. These num- bers range from 1 to 36.
Buss A pathway over which data travels.
Button Highlight Marker A Cell Marker that is used to turn on or turn off the Highlights for Buttons over Video.
C
Caption Text that appears on screen during a program, such as foreign language subtitles, commentary, program notes, etc.
CBR Constant Bit Rate encoding, which dig- itizes and compresses a video source using a single, unvarying encode rate, as opposed to VBR (see Variable Bit rate).
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Cell A contiguous length of video within a DVD presentation object (i.e. a “Track”) having a specific beginning marker and a specific ending marker. The video in between the markers is defined as the “cell”.
A Track may have one cell, or many cells.
Cell Command A DVD command inserted into the beginning marker of a DVD video cell, which defines the navigation action taken when that cell has completed its playback. This command does not exe- cute until the playback has reached the cell’s end marker. In DVD Studio Pro, these are the commands programmed into Track Markers, and cause inter- ruptions in the track’s playback at the next marker.
Cell Marker A Marker that is not defined as a Chapter Marker or a Program Marker.
CGMS (Copy Guard Management System) A method of preventing copies or controlling the num- ber of sequential copies allowed. CGMS/A is added to an analog signal, such as line 21 of NTSC. CGMS/D is added to a digital signal, such as IEEE 1394.
Channel One section of an audio track, usually carrying the sound for one speaker.
Chapter Properly known as a “Part of Title,”
(PTT) a point on a DVD that the viewer can instantly jump to, like a track on a CD. In DVD Studio Pro, this is a Marker within a Track (and also the division point between slides in a Slideshow).
Chapter Marker Chapter Markers define Chapter locations, which may be navigated to from a Menu, or may be skipped to by the DVD viewer while that Track is playing. In DVD Studio Pro, these are the highest priority of all of the various Markers.
Chroma The color part of a video signal, as well as a description of how intense the color is in a given frame.
Closed Caption A caption that is only visible when specifically decoded (and requiring a decoder of some kind), as opposed to “open captions,” which
are a permanent part of the picture image. DVD Studio Pro can process .CC files to add Closed Captions to your project.
CMF (Cutting Master Format) A protocol, sim- ilar to DDP, that describes data that will be recorded onto an optical disc. Developed by Pioneer, CMF can now be recorded directly to DVD-R for Authoring (4.7 GB) media using the Pioneer DVR-S201 recorder, but is not supported by the DVD-R General Media Format (i.e., the Superdrive). This allows a single DVD-R (A) disc to serve as both a check disc for testing playback, and as the replication master for saving time and ensuring accuracy of the data. DVD- R Cutting Master Format is written to the lead-in area, which has been specially reserved for master- ing applications and is defined in version 2.0 of the DVD-R for Authoring specification. Special software and some handling at a press facility are required to use the DVD-R Cutting Master. CMF may also be used to prepare a DLT master tape, but DDP is more commonly used, and more generally acceptable at replicators.
Coaxial Cable A two-conductor cable with a hot center wire and a neutral shield wire running along the same axis. Used to link a television to a DVD player, route digital audio signals, or to provide cable TV access.
CODEC Short for Compression/Decompression, a codec is a set of rules that govern the encoding (or compression) and decoding (or decompression) of media.
Color Balance The balance of different colors on a video monitor. Improperly balanced, the image will appear weighted toward one hue or another. The right balance can be achieved by using color reference bars.
Colorist The individual responsible for the look of a title when it is mastered to video, including adjust- ing not only the color and contrast, but also occa-
sionally the framing of the image (sometimes called a telecine colorist).
Combo Drive A DVD-ROM drive capable of reading and writing CD-R and CD-RW media. May also refer to a DVD-R, DVD-RW, or DVD+RW drive with the same capability.
Component Video A video system in which the video signal is divided into three parts, and trans- ferred through three individual wires, so that the color signals don’t interfere with one another. Many television sets are now equipped to receive a compo- nent video signal, which offers higher quality pic- tures than composite video.
Composite Video A video system in which all three colors (R, G, & B) and brightness (“Luminance”) are transferred over one wire. Single- cable outputs from both NTSC (the United States tel- evision standard) and PAL (the European television standard) DVD players and VCRs are typical exam- ples of composite video, which offers a lower qual- ity picture than component video. This is not a good format to use for encoding MPEG (unless you have nothing else). Composite video cables are typically color-coded Yellow.
Compression Any method of reducing the amount of space needed to record or transmit information. In DVDs, video is compressed using a process called variable bit rate encoding, which allots a changing number of bits to enhance resolution in a given scene.
Scenes with lots of light or little action require less hits than dark scenes or those with lots of action.
CPRM (Content Protection for Recordable Media) Copy protection for writable DVD for- mats.
CSS “Content Scramble System” One of the two types of encryption available in DVD, CSS scram- bles the DVD data in such a manner as to require a decrypting key for proper playback. The decrypting
keys are inserted during replication, and is typically not copyable if the DVD contents are digitally extracted without special software. CSS-encrypted masters are typically delivered on DLT, not DVD-R.
D
DDP (Disc Description Protocol) Acronym for the protocol that describes collections of data that are recorded onto a CD or DVD. DDP allows for auto- mated transfer of data from data publishers to disc manufacturers. DDP is the de-facto standard in the DVD industry for delivering disc image data to the replication plant for manufacturing. Originally devel- oped by Doug Carson & Associates, Inc. (DCA) for CD manufacturing, DDP provides descriptive infor- mation about the disc to be manufactured, such as the physical size, number of sides, etc. DVD Studio Pro utilizes both version 2.0 and 2.1 of this specification, information about which can be requested via the DCA website at www.dcainc.com.
Decode To take compressed, encoded sources and turn them into a data stream that can be played back by another device.
Decoder Hardware or software that can render an encoded file or bitstream playable. DVD Playback always requires an MPEG decoder of some kind.
Digital Compression Any scheme, method, or algorithm that reduces the storage space or data bandwidth required to record or transmit informa- tion. MPEG and JPEG are both digital compression schemes, as are Dolby Digital AC-3, MP3, AAC, MPEG-4, and other compression schemes.
DLT (Digital Linear Tape) A digital archive stan- dard using half-inch tapes. Commonly used for sub- mitting a premastered DVD disc image to a replication service. Drives are almost universally manufactured by Quantom, but marketed under a variety of trade names.
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DTS (Digital Theatre Systems) Another well- established format in the 5.1 channel surround sound market besides Dolby Digital. DTS is a Stereo or 5.1 channel surround format available for DVD or Audio CD. This format is similar to Dolby Digital, except that it uses less compression, and by consequence, a higher encoding rate. These features theoretically provide higher quality sound. Many DVD players do not provide integral DTS audio decoding, hence they require an external DTS decoder. DTS audio streams are supported in DVD Studio Pro 3 and 4, but not 2.
DSP Digital Signal Processor (or Processing) DSP is usually found on surround sound receivers, and in computerized DAWs (Digital Audio Workstations).
DSP uses digital algorithms to alter the way sound is heard. For example, setting the DSP to “Hall” would create an effect that sounded like you were in a Concert Hall. DSP can also be used to modify the level, frequency response, and many other character- istics of a sound file.
Direct Satellite System (DSS) DSS is a method used in broadcasting television. A small 18" dish can receive hundreds of channels with high quality digi- tal picture and sound.
Direct View Television Unlike Projection systems, a TV in which the picture is directly scanned on a CRT tube. This is the most typical television found in American homes. These TVs can vary in size from less than 12 to 40 inches or more.
Discrete Surround Sound Sound that has an indi- vidual channel for each speaker, with each channel handled separately.
Dolby Digital (a.k.a. Dolby 5.1) (see also AC-3) A six-channel digital surround sound system, using three speakers in the front (left, right, and center), split surrounds (left and right surround) and a sub- woofer for bass frequencies. The six-channel format was originally created by Dolby Labs for theatrical soundtracks and subsequently adapted for home use.
Originally known as AC-3, Dolby Digital is the most prevalent 5.1 channel surround sound format avail- able on DVD, and (with PCM) is one of the two worldwide DVD sound standards. Dolby Digital can encode a 5.1 channel surround sound program into a single bitstream, and then decompress this stream back into five discrete channels of sound, and a “.1”
subwoofer (LFE) channel. This recreates the original 5.1 soundtrack.
Dolby Pro Logic An audio coding system that allows four channels of sound to be encoded into two channels (stereo) and then decoded back into four channels (left, center, right, and surround). The cen- ter channel enables Dolby Pro Logic to reproduce theatrical soundtracks, especially Dialog, more fully than traditional Left/Right Stereo, while the Mono surround gives the “you are there” feeling. Dolby Pro Logic does not provide as rich a listening experience as Dolby Digital in the 5.1 mode.
Dolby Surround A encode/decode process cre- ated by Dolby that encodes four channels of audio (left, center, right, and surround) onto two audio channels, which are then decoded into three channels (left, right, and surround). Not as elaborate a sound system as either Dolby Pro Logic or Dolby Digital.
DTS (Digital Theater Systems) An audio format like Dolby. DTS has its own six-channel (5.1) encode/decode system for movie theaters and also sells a line of DVD videos and DVD-Audio titles that use its compression technique. Audio track DTS, however, requires almost four times as much space on a DVD disc than a Dolby track. DTS will only play in 5.1-channel sound on a system that has a DTS decoder.
Dual-Layer Breakpoint Marker A Marker used to designate the Chapter Marker at which a dual-layer DVD may shift playback from Layer 0 to Layer 1.
DVD Digital Video DiscDigital Versatile Disc DVD is the size of a standard CD, but it can hold
more information (4.7 gigabytes compared to 650 megabytes). DVD’s primary features include: Dolby Digital soundtracks, multiple aspect ratios, multiple spoken languages with multiple language subtitles, multiple camera angles, parental lockout, and addi- tional features that are at the discretion of the studio producing the disc. In addition, DVD is the highest resolution, consumer format available, with 500 lines of resolution. In comparison, VHS has 240, Super VHS has 400, and LD has 425 lines. For more infor- mation, check out the DVD FAQ by Jim Taylor.
DVD (see also Mini-DVD) Originally Digital Video Disc, then Digital Versatile Disc, DVD is the acronym for the 8 or 12 cm digital disc format pro- viding from 1 to about 17 billion bytes of data stor- age—commonly misused as a catch-all acronym for Digital Home Video, DVD is also a general format for data storage and delivery that includes several dif- ferent subformats: see also DVD-ROM, DVD-Audio, DVD-Video, DVD-R, DVD-RW, DVD-RAM.
DVD-1, 2, 3, 4 (also Mini-DVD) There is a stan- dard specified for the creation of Mini-DVD (8 cm) discs, with data structures identical to its big brother, but reduced capacities (1.46 GB SS/SL, 2.92 GB SS/DL). As of late 2000, the first Mini-DVD discs are finally making their way into some replication plants as a viable format.
DVD-5 Single-Sided, Single-Layer DVD disc, which can hold 4.7 billion bytes of data.
DVD-9 Single-Sided, Dual-Layer DVD disc, which can hold 8.5 billion bytes of data.
DVD-10 Dual-Sided, Single-Layer DVD disc, which can hold 9.4 billion bytes of data.
DVD-14 Dual-Sided DVD with one Single-Layer side, and one Dual-Layer side, which can hold around 14 billion bytes of data.
DVD-18 Dual-Sided, Dual-Layer DVD disc, which can hold around 17 billion bytes of data.
DVD-Audio Again using the DVD-ROM format for delivery, DVD-Audio is a specialized form of DVD that provides better-than-CD audio quality for music releases, while adding graphics and even some video capability to the disc. Previous forms of this (CD-I, CD-G) were built to enhance 44.1 kHz PCM Audio, and used the Compact Disc format. DVD- Audio allows sampling rates of up to 192 kHz (!) and data sample widths of up to 24 bits—the increased sampling rates provide better frequency response (fidelity) while the larger bit widths provide better dynamic range.
DVD-ROM In its most basic incarnation, DVD- ROM in the underlying technology that allows 4.7 Billion Bytes of data to be stored and retrieved from a 12 cm data disc. DVD-ROM can be used to dis- tribute computer-readable data, which are cross-plat- form compatible (Mac/PC). No, this doesn’t mean your Mac will suddenly be able to run a Windows program, but it DOES mean that both platforms (and all others with DVD-ROM drives) will be able to read compatible data from the same DVD disc. The cross-platform magic is accomplished by the Micro UDF file format.
DVD-Video Built on the DVD-ROM disc (above) as a delivery vehicle, DVD-Video is a specialized form of DVD that can provide multiple selectable broadcast-quality video streams, digital audio streams, and subpicture (graphics) streams.
Originally designed for Home Entertainment (Movies on DVD), the DVD Video format is being increasingly used for Corporate and Industrial Communications, Kiosks, point-of-interest displays, and, refreshingly, education and training!
DVD-R (recordable) A form of DVD that allows the creation of a DVD-5 equivalent by a laser- equipped writing device (“DVD burner”). Typically used in conjunction with a DVD formatting program (Adaptec TOAST on Macs, Prassi DVD-Rep (or many similar) on Windows), and utilizing a specific
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