Blu-ray Disc is an optical disc storage media format. Its main uses are high-definition video and data storage. It is also the format used by Playstation 3 console system.
Compatible with Profile 2.0. Adds network connectivity for extra contents.
A single layered Blu-ray disc with 25GB capacity.
A double layered Blu-ray disc with 50GB capacity.
BD-9 is a red laser DVD with BD contents on it. Capacity: 9GB.
The Blu-ray Disc Association (BDA) is the industry consortium that develops and licenses Blu-ray Disc technology and is responsible for establishing format standards and promoting business opportunities for Blu-ray Disc. The BDA is divided into three levels of membership: the Board of Directors, the Contributors, and the General Members.
The “Blu-ray Disc Founder group” was started in May 2002 by nine leading electronic companies: Sony, Matsushita, Pioneer, Philips, Thomson, LG Electronics, Hitachi, Sharp, and Samsung. Spearheaded by Sony Corporation, on February 19th 2002 the companies announced that they were the “Founders” of the Blu-ray Disc and later changed their name to the “Blu-ray Disc Association” on May 18, 2004 to allow more companies to join their development. Some examples of companies that signed in include Apple, TDK, Dell, Hewlett Packard, The Walt Disney Company, Warner Bros. and Universal Music Group. As of December 2007, there are more than 250 members and supporters of the Association.
The term bitstream is frequently used to describe the configuration data to be loaded into a field programmable gate array (FPGA). This usage may have originated based on the common method of configuring the FPGA from a serial bit stream, typically from a serial PROM or flash memory chip, although most FPGAs also support a byte-parallel loading method as well. The detailed format of the bitstream for a particular FPGA chip is usually considered proprietary to the FPGA vendor.
Bonus material that can be played during the movie. Picture in picture content.
Codecs are compression schemes that store audio and video more efficiently, either giving longer play time or higher quality per megabyte. There are both lossy and lossless compression techniques.
The BD-ROM specification mandates certain codec compatibilities for both hardware decoders (players) and the movie-software (content). For video, all players are required to support MPEG-2, H.264/AVC, and SMPTE VC-1. MPEG-2 is the codec used on regular DVDs, which allows backwards compatibility. H.264/AVC was developed by MPEG and VCEG as a modern successor of MPEG-4. VC-1 is another MPEG-4 derivative codec mostly developed by Microsoft. BD-ROM titles with video must store video using one of the three mandatory codecs. Multiple codecs on a single title are allowed.
the process of encoding information using fewer bits (or other information-bearing units) than an unencoded representation would use through use of specific encoding schemes. One popular instance of compression with which many computer users are familiar is the ZIP file format, which, as well as providing compression, acts as an archiver, storing many source files in a single destination output file.
As with any communication, compressed data communication only works when both the sender and receiver of the information understand the encoding scheme. For example, this text makes sense only if the receiver understands that it is intended to be interpreted as characters representing the English language. Similarly, compressed data can only be understood if the decoding method is known by the receiver.
Digital rights management
The Blu-ray Disc format employs several layers of digital rights management.
Advanced Access Content System (AACS) is a standard for content distribution and digital rights management. It is developed by AS Licensing Administrator, LLC (AACS LA), a consortium that includes Disney, Intel, Microsoft, Matsushita (Panasonic), Warner Bros., IBM, Toshiba and Sony.
Since appearing in devices in 2006, several successful attacks have been made on the format. The first known attack relied on the trusted client problem. In addition, decryption keys have been extracted from a weakly protected player (WinDVD). However, even though some AACS cryptographic keys have been compromised, new releases will use new, uncompromised keys.
High-bandwidth Digital Content Protection (HDCP) is a form of digital copy protection developed by Intel Corporation to protect digital audio and video content as it travels across DisplayPort, Digital Visual Interface (DVI), High-Definition Multimedia Interface (HDMI), Gigabit Video Interface (GVIF), or Unified Display Interface (UDI) connections. The specification is proprietary, and implementing HDCP requires a license.
The High-Definition Multimedia Interface (HDMI) is a compact audio/video connector interface for transmitting uncompressed digital streams. It represents a digital alternative to consumer analog standards such as Radio Frequency (RF) coaxial cable, composite video, S-Video, SCART, component video, D-Terminal, and VGA.
Letterboxing is the practice of transferring widescreen film to video formats while preserving the film’s original aspect ratio. Since the video display often has a square aspect ratio, the resulting videographic image has mattes (black bars) above and below it; LTBX is the identifying acronym for films and images so formatted.
Letterboxing is the alternative to the full-screen, pan-and-scan transference of a widescreen film image to videotape or videodisc. In pan-and-scan transfers, the original image is cropped to the 1.33:1 (4:3) aspect ratio of the standard television screen, whereas letterboxing preserves the film’s original image composition seen in the cinema.
Lossless: Refers to audio that has been reproduced from the original source (Blu-ray disc, CD, eg.) without compressing the audio with compression codecs. Uncompressed PCM, Dolby True HD, and DTS-HD MA are examples of lossless audio feeds. All Blu-ray players are capable of transmitting uncompressed PCM data to a receiver using an HDMI cable. Not all players are capable of decoding/transmitting every type of compressed data. See your player’s user manual for details. See Compression. For comparison, See Lossy.
Lossy: Refers to audio that has been compressed with codec. During the recording/compression process, information has been lost, and may result in the perception of less quality/depth/richness of sound. Not all players are capable of decoding/transmitting every type of compressed data. See your player’s user manual for details. Examples of Lossy sound compression methods include DTS, Dolby Digital, and DTS-HD HR. See Compression. For comparison, See Lossless.
Manufacturer’s Suggested Retail Price.
Original Aspect Ratio.
Pulse-code modulation (PCM) is a digital representation of an analog signal where the magnitude of the signal is sampled regularly at uniform intervals, then quantized to a series of symbols in a digital (usually binary) code. PCM has been used in digital telephone systems and is also the standard form for digital audio in computers and the compact disc red book format. It is also standard in digital video, for example, using ITU-R BT.601. However, straight PCM is not typically used for video in standard definition consumer applications such as DVD or DVR because the bit rate required is far too high. Very frequently, PCM encoding facilitates digital transmission from one point to another (within a given system, or geographically) in serial form.
The pillar box effect occurs in widescreen video displays when black bars (mattes or masking) are placed on the sides of the image.
It becomes necessary when film or video that was not originally designed for widescreen is shown on a widescreen display, or a narrower widescreen image is displayed within a wider aspect ratio, such as a 1.85:1 image in a 2.35:1 frame. The original material is shrunk and placed in the middle of the widescreen frame. Some older arcade games that had a tall vertical and short horizontal are displayed in pillar box even on 4:3 televisions. Some early sound films made 1928–1931, such as City Lights, were filmed in an even narrower format to make room for the Sound-on-film track on then-standard film stock. These will appear pillar-boxed even on 4:3 screens.
Posterization of a photographic image being developed occurs when a region of an image with a continuous gradation of tone is replaced with several regions of fewer tones, resulting in an abrupt change from one tone to another. This creates an effect somewhat similar to that of a simple graphic poster. The effect may be created deliberately, or happen accidentally.
Blu-ray Discs may be encoded with a region code, intended to restrict the area of the world in which they can be played, similar in principle to the DVD region codes, although the used geographical regions differ. Blu-ray Disc players sold in a certain region may only play discs encoded for that region. The purpose of this system is to allow motion picture studios to control the various aspects of a release (including content, date, and, in particular, price) according to the region. Discs may also be produced without region coding, so they can be played on all devices.
Windowboxing (also called the “postage stamp effect”) occurs when the aspect ratio of a film is such that the letterbox effect and pillarbox effect occur simultaneously. Sometimes, by accident or design, a standard ratio image is presented in the central portion of a letterbox picture, resulting in a black border all around. It is generally disliked because it wastes a lot of screen space and reduces the resolution of the original image. It can occur when a 16:9 film is set to 4:3 (letterbox), but then shown on a 16:9 TV or other output device. It can also occur in the opposite direction (4:3 to 16:9 to 4:3). Few films have been released with this aspect ratio — one example is The Crocodile Hunter: Collision Course, which had numerous scenes of widescreen pillar boxing.