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Blu-ray Disc Recordable (BD-R) and Blu-ray Disc Recordable Erasable (BD-RE) refer to two direct to disc optical disc recording technologies that can be recorded on to a Blu-ray-based optical disc with an optical disc recorder. BD-R discs can only be written to once, whereas BD-RE discs can be erased and re-recorded multiple times, similar to CD-R and CD-RW for a compact disc (CD). Disc capacities are 25 GB for single-layer discs, 50 GB for double-layer discs, [1] 100 GB ("XL") for triple-layer, and 128 GB for quadruple-layer (in BD-R only). [2] [3]
The minimum speed at which a Blu-ray Disc can be written is 36 megabits (4.5 megabytes) per second. [4]
As of 2024, one of the primary pioneers of the Blu-ray disc, Sony, is winding down production of recordable Blu-ray discs in its plant in Tagajo, Japan. Sony plans to gradually cease its manufacturing of optical media, including recordable Blu-ray discs. [5]
As of November 2022 [update] , there are five versions of BD-RE and four versions of BD-R formats. Each version includes three Parts (a.k.a. Books): Basic Format Specifications, File System Specifications, Audio Visual Basic Specifications. Each part has sub-versions (e.g. R2 Format Specification includes Part 3: Audio Visual Basic Specifications Ver.3.02, Part 2: File System Specifications Ver. 1.11, Part 1: Basic Format Specifications Ver. 1.3). [6] [7] [8]
Date | RE Version | R Version | By Parts [8] [a] | Changes | ||
---|---|---|---|---|---|---|
Part 1 | Part 2 | Part 3 | ||||
2002 | 1.0 [9] | RE V1.0 | RE V1.0 | RE V1.0 | ||
2005 | 2.0 [12] | 1.0 | RE V2.1 R V1.3 | RE V2.1 R V1.1 | RE V2.1 | |
September 2006 | 3.0 [16] | 2.0 [6] | RE V2.1 R V1.3 | RE V2.1 R V1.1 | RE V3.0 + ROM V2.4 (BDMV) |
|
June 2010 | 4.0 [17] | 3.0 [18] | RE V3.0 R V2.0 | RE V3.0 R V2.0 | RE V4.0 + RE V2.1 | New BDXL definition:
|
December 2017 | 5.0 [20] | 4.0 [21] | RE V3.1 R V2.2 | RE V4.0 R V3.0 | RE V5.0 | BDXL expansions:
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Inspite of having the "Blu-ray" brand, "BDXL" is separate from the original "BD" format, meaning existing Blu-ray drives that predate the release of BDXL (mid-2010) do not support BDXL. Even Blu-ray drives released after then do not necessarily support BDXL unless explicitly stated. [22]
Type | Data layers | Capacity | First released in year |
---|---|---|---|
BD-R, BD-RE (single-layer) | 1 | 25 GB (25,025,314,816 bytes) | 2006 |
BD-R DL, BD-RE DL (dual-layer) | 2 | 50 GB (50,050,629,632 bytes) | |
BD-R XL, BD-RE XL (triple-layer) | 3 | 100 GB (100,103,356,416 bytes) | 2010 |
BD-R XL (quadruple-layer) | 4 | 128 GB (128,001,769,472 bytes) |
A single-layer Blu-ray disc (BD-R and BD-RE) has a capacity of 25,025,314,816 bytes, which are 23,866 MiB. A dual-layer Blu-ray disc (BD-R DL and BD-RE DL) has 50,050,629,632 bytes, which are 47,732 MiB. This is exactly twice the capacity, unlike dual-layer DVDs, which only have less than twice the capacity as single-layer DVDs. [23]
BDXL discs store more per data layer, roughly 30 GiB, so they are able to store 100 GB in only three instead of four layers. No single-layer variant for BDXL exists, given that a first-generation BD-R DL disc already exceeds the capacity of one layer of a BDXL. There are variants with 100 GB and 128 GB, the latter of which has slightly less capacity per data layer but one additional data layer. A 100 GB BDXL has three data layers and 100,103,356,416 bytes (95,466 MiB) of capacity, which is 2 MiB less than twice the capacity of a BD-R(E) DL, and a 128 GB BDXL has four data layers and 128,001,769,472 bytes (122,072 MiB) of capacity and only exists as write-once variant (BD-R XL). [23]
This area is referred to as the "Volume Space" in the UDF specification, and stores the file system, names of files and folders, and the file contents. [24] The same area is referred to as the "program area" on the CD. [25] Other information such as where the disc sessions and tracks are located and their length are stored outside this area.
If the spare area is enabled, 256 MiB (268.435.456 bytes) are taken away from the "Volume Space" and reserved for the spare area. Within the "Volume Space", the capacity that can be occupied by the content of files is also slightly reduced by file system overhead and by slack space as well, but the amount of slack space is trivial given that file systems on optical discs use a low cluster size (also referred to as "logical sector size") of 2 KiB (2048 bytes), matching the size of a single physical sector on optical discs. With packet writing, the file system overhead is larger. [26]
The spare area is where the drive stores addresses for unreadable sectors so they are replaced with new data in case. This is known as defect management and is handled internally by the drive, not by the computer's operating system. On some earlier formats, including the CD-RW and DVD±RW, defect management has to be handled by the UDF file system, meaning by the computer, also referred to as the "host" system. [27] [28]
As of December 2018 [update] , the following speeds are seen in Blu-Ray specifications for R/RE discs: [8]
Drive speed | Data rate | 25 GB BD-R(E) write time | 50 GB BD-R(E) DL (25 GB/layer) write time | 100 GB BD-R(E) XL TL (~33 GB/layer) write time | ||
---|---|---|---|---|---|---|
1× [1] | 36 Mbit/s | 4.5 MB/s | 4.29 MiB/s | ~95 min. | ~190 min. | ~380 min. |
2× | 72 Mbit/s | 9 MB/s | 8.58 MiB/s | ~47 min. | ~94 min. | ~188 min. |
4× | 144 Mbit/s | 18 MB/s | 17.17 MiB/s | ~24 min. | ~48 min. | ~96 min. |
6× | 216 Mbit/s | 27 MB/s | 25.75 MiB/s | ~16 min. | ~32 min. | ~64 min. |
8× | 288 Mbit/s | 36 MB/s | ~34.32 MiB/s | ~11.25 min. | ~22.5 min. | ~45 min. |
10× | 360 Mbit/s | 45 MB/s | 42.898 MiB/s | ~9 min. | ~18 min. | ~36 min. |
12× | 432 Mbit/s | 54 MB/s | ~51.48 MiB/s | ~7.5 min. | ~15 min. | ~30 min. |
14× | 504 Mbit/s | 63 MB/s | ~60 MiB/s | ~6.5 min. | ~13 min. | ~26 min. |
16× | 576 Mbit/s | 72 MB/s | ~68.64 MiB/s | ~5.7 min. | ~11.5 min. | ~23 min. |
2× speeds are mandatory for all formats, with 4× and 6× being optional for non-XL BD-R media. Since BD-RE 5.0/BD-R 4.0, a read speed of 4× is mandatory for UHD support. [8]
Note: If write verification is enabled, as it may be by default on some burning software, the write will take longer to complete. Erasing a BD-RE is not necessary since existing data can be directly overwritten. Unlike with CD-RW, there is no need for blanking BD-RE before re-use, but they need to be formatted before first use. Burn programs may detect the unformatted state and automatically format the medium before beginning to write. [29]
Write verification is a feature of formatted Blu-ray media, officially called "Defect Management". Similar functionality existed on DVD-RAM and on Mount Rainer-supporting disc drives, but BD-R is the first write-once media with such functionality. If not deactivated, the correctness of the written data is verified immediately after being written. Poorly readable data can be written again to an area of spare blocks, but the writing speed is halved during the entire writing process because only half of the disc rotations are for writing. Defect management can be deactivated by burn programs using a feature called "Stream Recording" which enables full nominal write speed. Whether defect management is beneficial with mediocre media depends much on the individual medium and the drive's firmware. It works well with narrowly located bad spots but tends to fail more often than stream recording if the drive perceives reduced read quality on the whole medium. It may be desirable to deactivate write verification on undamaged media to save time when mass-producing physical copies of data, since errors are unlikely to occur on physically undamaged media. [30] [31]
As of April 2018 [update] (approximate pricing):
Instead of the pits and lands found on prepressed/prerecorded/replicated discs, BD-R and RE discs contain grooves which contain a wobble frequency that is used to locate the position of the reading or writing laser on the disc. [40] BD-R has an Optimum Power Calibrations (OPC) / Test Zone, which is used to calibrate (finely adjust) the power of the writing laser before and during writing, and it also has a Drive Calibration Zone (DCZ) at the outer edge of the disc, for optional high speed calibration. The calibration is necessary to allow for slight manufacturing defects, greatly reducing or completely eliminating rejected discs and drives, reducing costs and eliminating potential waste. The information below describes the different types of recording layers that may be used on BD-R and BD-RE discs.
"Normal" BD-R discs use a composite (or, in the case of BD-RE, a phase-changing alloy) that decreases its reflectivity on recording, i.e. "High To Low". [41] Sony, for example, uses an inorganic [42] composite that splits into two laminar components with low reflectivity. [43] Composites used may include BiN, Ge3N4, and Pd-doped tellurium suboxide. [44] A pair of layers with copper alloy and silicon that combines on recording may alternatively be used. [45] Similar to CD-RW and DVD-RW, a phase transition alloy (often GeSbTe or InAgTeSb; copper silicate (CuSi) or other alloys can also be used, like Verbatim's proprietary MABL) [46] [45] [47] is used for BD-RE discs. Melting the material with a very high power beam turns it into an amorphous state with low reflectivity, while heating at a lower power erases it back to a crystalline state with high reflectivity. [48]
In BD-RE discs, the data layers are surrounded by a pair of dielectric Zinc Sulfur-Silicon Dioxide layers. [3] [49] An adhesive spacer layer and a semi-reflective layer are used for multi-layer discs. [45] [50] The recording and dielectric layers are all deposited using Sputtering. [49] On multi-layer BD-RE discs, each GeSbTe recording layer is progressively thinner. So the first layer (L0) is 10 nm thick, L1 is 7.5 nm thick, L2 is 6 nm thick, and so on. The silver alloy reflective layers that are behind each recording layer also become progressively thinner, so the L0 silver layer is 10 nm thick, the L1 layer is 9 nm thick, the L2 layer is 7 nm thick, and so on. The separation layers that separate the recording layers from one another also progressively become thinner. [51] [52]
BD-R LTH is a write-once Blu-ray Disc format that features an organic dye recording layer. "Low To High" refers to the reflectivity changing from low to high during the burning process, which is the opposite of normal Blu-rays, whose reflectivity changes from high to low during writing. The advantage of BD-R LTH is it can protect a manufacturer's investment in DVD-R/CD-R manufacturing equipment because it does not require investing in new production lines and manufacturing equipment. Instead, the manufacturer only needs to modify current equipment. This is expected to lower the cost of disc manufacturing. [53]
Old Blu-ray players and recorders cannot utilize BD-R LTH; however, a firmware upgrade can enable devices to access BD-R LTH. Panasonic released such a firmware update in November 2007 for its DMR-BW200, DMR-BR100 and MR-BW900/BW800/BW700 models. [54] Pioneer was expected to ship the first LTH BD drives in Spring 2008. [55] Sony upgraded the PlayStation 3 firmware enabling BD-R LTH reading in March, 2008. [56]
In 2011, France's Ministry of Culture and Communication conducted a study on the suitability of data archival of LTH (low to high) discs compared to HTL (high to low) discs. The data they collected indicated that the overall quality of LTH discs is worse than HTL discs. [57] [58]
An optical disc is a flat, usually disc-shaped object that stores information in the form of physical variations on its surface that can be read with the aid of a beam of light. Optical discs can be reflective, where the light source and detector are on the same side of the disc, or transmissive, where light shines through the disc to be detected on the other side.
Universal Disk Format (UDF) is an open, vendor-neutral file system for computer data storage for a broad range of media. In practice, it has been most widely used for DVDs and newer optical disc formats, supplanting ISO 9660. Due to its design, it is very well suited to incremental updates on both write-once and re-writable optical media. UDF was developed and maintained by the Optical Storage Technology Association (OSTA).
In computing, an optical disc drive (ODD) is a disc drive that uses laser light or electromagnetic waves within or near the visible light spectrum as part of the process of reading or writing data to or from optical discs. Some drives can only read from certain discs, while other drives can both read and record. Those drives are called burners or writers since they physically burn the data onto on the discs. Compact discs, DVDs, and Blu-ray discs are common types of optical media which can be read and recorded by such drives.
Optical disc authoring, including CD, DVD, and Blu-ray Disc authoring, is the process of assembling source material—video, audio or other data—into the proper logical volume format to then be recorded ("burned") onto an optical disc. This act is sometimes done illegally, by pirating copyrighted material without permission from the original artists.
DVD-RAM is a DVD-based disc specification presented in 1996 by the DVD Forum, which specifies rewritable DVD-RAM media and the appropriate DVD writers. DVD-RAM media have been used in computers as well as camcorders and personal video recorders since 1998.
The Blu-ray Disc Association (BDA) is the industry consortium that develops and licenses Blu-ray 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, contributors, and general members.
MultiLevel Recording is a technology originally developed by Optex Corporation and promoted by Calimetrics to increase the storage capacity of optical discs. It failed to establish itself on the market. Through a combination of proprietary media, recorder, reader and player modifications, Calimetrics proposed that ML could increase the capacity of a CD-ROM, CD-R or CD-RW to 2 GB, a single-layer DVD, DVD-R, DVD+R, DVD-RW, DVD+RW or DVD-RAM to 7.1 to 10 GB and a single-layer Blu-ray Disc (BD) to as much as 60 GB. An optionally integrated digital rights management (DRM) system entitled MovieGuard was also suggested. An industry group called the ML Alliance was formed in 2000 to help commercialize ML technology. Members eventually included Calimetrics, TDK, Sanyo Semiconductor, Plextor, Matsushita Kotobuki Electronics, Mitsubishi Chemical Corporation, Verbatim, Teac and Yamaha.
The double-density compact disc (DDCD) is an optical disc technology developed by Sony and Philips using the same 780 nm laser wavelength as a compact disc. The format was announced in July 2000 and is defined by the Purple Book standard document. Unlike the compact-disc technology it is based on, DDCD was designed exclusively for data, with no audio capabilities.
Optical storage refers to a class of data storage systems that use light to read or write data to an underlying optical media. Although a number of optical formats have been used over time, the most common examples are optical disks like the compact disc (CD) and DVD. Reading and writing methods have also varied over time, but most modern systems as of 2023 use lasers as the light source and use it both for reading and writing to the discs. Britannica notes that it "uses low-power laser beams to record and retrieve digital (binary) data."
DVD recordable and DVD rewritable are a collection of optical disc formats that can be written to by a DVD recorder and by computers using a DVD writer. The "recordable" discs are write-once read-many (WORM) media, where as "rewritable" discs are able to be erased and rewritten. Data is written ("burned") to the disc by a laser, rather than the data being "pressed" onto the disc during manufacture, like a DVD-ROM. Pressing is used in mass production, primarily for the distribution of home video.
CD-RW is a digital optical disc storage format introduced by Ricoh in 1997. A CD-RW compact disc (CD-RWs) can be written, read, erased, and re-written.
AVCHD is a file-based format for the digital recording and playback of high-definition video. It is H.264 and Dolby AC-3 packaged into the MPEG transport stream, with a set of constraints designed around camcorders.
dvd+rw-tools is a collection of open-source DVD and Blu-ray Disc tools for Linux, OpenBSD, NetBSD, FreeBSD, Solaris, HP-UX, IRIX, Windows and OS X. dvd+rw-tools does not operate on CD media.
This article compares the technical specifications of multiple high-definition formats, including HD DVD and Blu-ray Disc; two mutually incompatible, high-definition optical disc formats that, beginning in 2006, attempted to improve upon and eventually replace the DVD standard. The two formats remained in a format war until February 19, 2008, when Toshiba, HD DVD's creator, announced plans to cease development, manufacturing and marketing of HD DVD players and recorders.
The DVD is a digital optical disc data storage format. It was invented and developed in 1995 and first released on November 1, 1996, in Japan. The medium can store any kind of digital data and has been widely used to store video programs, software and other computer files. DVDs offer significantly higher storage capacity than compact discs (CD) while having the same dimensions. A standard single-layer DVD can store up to 4.7 GB of data, a dual-layer DVD up to 8.5 GB. Variants can store up to a maximum of 17.08 GB.
Blu-ray is a digital optical disc data storage format designed to supersede the DVD format. It was invented and developed in 2005 and released worldwide on June 20, 2006, capable of storing several hours of high-definition video. The main application of Blu-ray is as a medium for video material such as feature films and for the physical distribution of video games for the PlayStation 3, PlayStation 4, PlayStation 5, Xbox One, and Xbox Series X. The name refers to the blue laser used to read the disc, which allows information to be stored at a greater density than is possible with the longer-wavelength red laser used for DVDs, resulting in an increased capacity.
HD DVD is an obsolete high-density optical disc format for storing data and playback of high-definition video. Supported principally by Toshiba, HD DVD was envisioned to be the successor to the standard DVD format, but lost to Blu-ray, supported by Sony and others.
In computing, the burst cutting area (BCA) or narrow burst cutting area (NBCA) is the circular area near the center of a DVD, HD DVD or Blu-ray Disc, where a barcode can be written for additional information such as ID codes, manufacturing information, and serial numbers. The BCA can be written during mastering and will be common for all discs from that master or, more usually, will be written using a YAG laser to “cut” the barcode into the aluminum reflective layer of the finished disc, potentially adding a unique barcode to each manufactured disc.
M-DISC is a write-once optical disc technology introduced in 2009 by Millenniata, Inc. and available as DVD and Blu-ray discs.
Ultra HD Blu-ray is a digital optical disc data storage format that is an enhanced variant of Blu-ray. Ultra HD Blu-ray supports 4K UHD video at frame rates up to 60 progressive frames per second, encoded using High-Efficiency Video Coding. These discs are incompatible with existing standard Blu-ray players.
Defect management comes with a performance penalty: most units will typically record at about 1/2 of the advertised media speed. This is because such units will spend every second revolution verifying the newly recorded data for defects.
growisofs allows for SRM recordings without spare area through "undocumented" -use-the-force-luke=spare:none
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