Compiled by Shane Matsumoto - Copyright 2008 All Rights Reserved
1080p: Shorthand for a particular HDTV video mode. 1080 is the number of lines of virtical display resolution. The letter “p” indicates progressive scan and non-interlaced. Usually associated with widescreen and a 16:9 aspect ratio with a horizontal resolution display of 1920 pixels across.
1080i: HDTV video mode shorthand for 1080 lines of vertical resolution and interlaced or non-progressive scan. Usually indicates a frame resolution of 1920x1080.
720p: HDTV video mode shorthand for 720 lines of vertical resolution and progressive scan.
720i: HDTV video mode shorthand for 720 lines of vertical resolution and interlaced scan.
AACS: Advanced Access Content System. Copy protection system primarily used to protect HD video content formatted on both Blu-ray and HD DVD Discs.
AC3: Also known as Dolby Digital audio format. NTSC DVD titles use this audio compression format with MPEG-2 video. This digital format carries up to six channels and is compatible with BD authoring specs though HD formats tend to use uncompressed audio.
AES128: Advanced Encryption Standard (AES). This encryption has a fixed block size of 128 bits and a key size of 128, 192 or 256 bits.
Anamorphic: A process of storing images with different horizontal and vertical magnifications for later display through a reversed procedure.
Aspect Ratio: Width x height. Aspect ratio is a way of expressing the ratio of a display screen. For example: 16x9 means 16 units wide by 9 units high.
AVC: Advanced Video Coding. Also known as H.264 or MPEG-4. The most common video codec employed for BD video prior to the multiplexing stage in authoring.
BD+: A DRM system, different from AACS, for Blu-ray discs.
BD: Blu-ray Disc.
BD-ROM: Blu-ray Disc Read-Only Memory. A Blu-ray Disc with pre-recorded content. These are usually replicated discs although sometimes referring to closed-session content after it is recorded to BD-R discs. May contain content such as HD movies, music, software, games, etc.
BD-R: Blu-ray Disc Recordable. BD format for video recording and PC data storage.
BD-RE: Blu-ray Disc Rewritable. BD rewritable disc format.
Bandwidth: In reference to DVD authoring this concept is usually conveyed as a bitrate. Bandwidth is essentially the amount of data that can be handled in a specific increment of time (i.e. “megabits per second”).
Bitrate: The amount of data required to process video playback without interruption. For BD video, authoring bitrates are usually expressed in Mbs (megabits per second). The higher the bitrate, the higher the quality but the more bandwidth and processing power is required to playback without interruption.
Blu-ray Disc: Abbreviated as BD and is often just shortened to “Blu-ray”, is the optical disc format most likely to become the standard for PC data storage, and recording, rewriting, and playback of high-definition video. The name “Blu-ray” is probably short for “blue laser optical ray” and comes from the blue-violet laser the technology is based on which reads and writes data. The letter “e” was dropped from the word “Blue” in “Blu-ray” so the term could be registered as a trademark by the Blu-ray Disc Association.
CBR: Constant Bit Rate. An encoding or decoding method using consistent rate of Bandwidth. CBR encoding uses the same amount of data per second as opposed to variable bit rate (VBR).
Codec: Short for “coder-decoder” or “encode-decode”. A general term for compression standards and translators to deliver digital media in a condensed fashion. Different codecs determine file size and quality of encoded audio and video.
DRM: Digital Restrictions Management or Digital Rights Management
DVI: Digital Visual Interface. Video Interface standard able to carry HD video and typically used for digital projectors and
Frame Rate: The amount of frames displayed each second a video is played.
H.264, also MPEG-4: See AVC.
HDCP: High-Definition Content Protection. A copy protection system that downgrades the Hi Definition signal if signal passes through a video device that doesn’t support the protocol. If HDCP present in the video signal, all video gear in the playback chain (TV/Monitor, disc player, etc.) must support this protocol otherwise the HD signal drops to VHS comparable quality or will not display at all. Usually transmitted via DVI or HDMI digital connections.
HDMI: High-Definition Multimedia Interface. A single digital HDMI interface transmits both audio and video streams uncompressed as well as HDCP. This has become the consumer digital standard protocol for High-Definition signals replacing analog counterparts like component, composite, SCART, or RCA.
HDTV: High Definition Television. Consumer-speak for any display that supports higher quality picture images than standard definition. HDTV sets generally display 720 up to 1080 visible lines to display video.
Interlacing: Drawing a frame by alternately drawing the rows of each field. For example, an NTSC broadcast is expressed as 30 frames per second, but is actually made up of 60 half-frames displayed one after the other. The alternative is de-interlacing, where only complete frames are drawn on the screen.
Layers: In respect to Blu-ray Discs, each layer of data on a single side can hold 25GB of data. Dual-layered Blu-ray discs can hold 50GB of data. As of the writing of this glossary, there are working prototypes of BD media able to hold 200GB of data, or BD with four layers. Layers are transparent to BD reading/writing lasers if other layers are being read or written to. BD lasers re-focus to whichever layer is being utilized.
MPEG-1: Motion Picture Export Group.
MPEG-2: Pre-muxed video codec for BD video. This codec is used exclusively in DVD video, but not used on BD commercial releases as commonly as AVC/MPEG-4.
Also, a DVD audio compression format used in PAL releases. MPEG-2 as an audio format is optional for BD authored video but is not very common.
MPEG-4, also H.264: See AVC
Multiplexing: Sometimes referred to as “muxing”. The part of the video authoring process that takes multiple streams of digital data (like .AC3 audio and MPEG-2 video) and interleave it into one signal (like a .VOB video file on a DVD).
NTSC: National Television Systems Committee: A committee of the Electronic Industries Association. Also a video format used in North America, Japan and select parts of Central and South America. NTSC format has 525 scan lines (rows) of resolution at thirty frames per second (30 Hz).
PAL: Phase Alteration Line. As opposed to NTSC, this is the standard for commercial broadcasting in most of the world. Pal format displays at 625 scan lines (rows) of resolution at 25 frames per second (25 Hz).
SDTV: Standard Definition Television. Television sets based on the NTSC or PAL standards. SDTV supports 480 to 570 visible lines to display video.
VBR: An encoding/decoding method that determines which parts of a video are more complex and uses a higher bitrate for those sections and a lower bitrate for the simpler sections.
VC-1: One of the 3 video codecs compatible with BD for HD video. Codec is based on Windows Media Video Version 9. VC-1 decodes HD video twice as fast as H.264 and offers as much as three times better compression than MPEG-2 but is not as commonly used as H.264.
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