Layer Jump Recording (LJR)
Encyclopedia
Layer Jump Recording is a writing method used for DVD-R DL (Dual Layer)
.
It permits recording the disc per increments called session (see Optical disc authoring
), aka multi-session. It also permits a faster closing of the disc by saving extraneous padding when the amount of recorded data does not fill-up the disc. It overcomes these limitations of Sequential Recording (SR), the writing method usually applied to write-once optical media.
The layer jump is a switch (jump) between the layer closer to the laser head (referred as L0) to the farther layer (referred as L1), or vice-versa. Jumping layers is already necessary for reading multiple layer optical media (so far market released products are limited to two layers despite some research prototypes having up to eight layers), as well as for recording them with Sequential Recording. However the layer jump during the recording occurs only once, at the position called Middle Area, during a Sequential Recording, while it may occur multiple times with Layer Jump Recording.
Two different Layer Jump methods are defined: Manual Layer Jump and Regular Layer Jump. The first require the software
to specify to the hardware each jump point from layer zero to layer one (the jump from layer one to layer zero occurring always at the symmetric jump point). The latter requires the software to specify to the hardware only once the jumping interval size.
This technology was championed by Pioneer Corporation
, optical device manufacturer among things, and introduced to the market in 2005. The physical part of the technology was first specified within DVD Forum
, and then a matching device command set was introduced to the Mt Fuji specification (which eventually was replicated within the MMC specification
). Later the Layer Jump Recording impacted the UDF file system specification
.
Unlike most recording methods, Layer Jump Recording was not unanimously adopted by optical driver manufacturer. The limited backward compatibility with legacy optical devices, complexity of device firmware
implementation, need of significant software update for support and the slightly awkward writing sequencing, slowed down the adoption. In 2006, drives supporting the Layer Jump Recording methods were released by Pioneer itself, Plextor
, BenQ
, Lite-On
, and Sony
. The technology was also supported by optical drive chipsets from key manufacturer MediaTek.
The technology is supported by multiple recording software, but also not unanimously supported. Nero
, Sonic/Roxio
, CyberLink
and Ulead Systems
claim support for Layer Jump Recording in their software.
DVD-R DL
DVD-R DL , also called DVD-R9, is a derivative of the DVD-R format standard. DVD-R DL discs hold 8.54 GB per side by utilizing two recordable dye layers, each capable of storing nearly the 4.7 gigabyte of a single layer disc -almost doubling the total disc capacity...
.
It permits recording the disc per increments called session (see Optical disc authoring
Optical disc authoring
Optical disc authoring, including 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 onto an optical disc .-Process:To burn an optical disc, one usually first creates an...
), aka multi-session. It also permits a faster closing of the disc by saving extraneous padding when the amount of recorded data does not fill-up the disc. It overcomes these limitations of Sequential Recording (SR), the writing method usually applied to write-once optical media.
The layer jump is a switch (jump) between the layer closer to the laser head (referred as L0) to the farther layer (referred as L1), or vice-versa. Jumping layers is already necessary for reading multiple layer optical media (so far market released products are limited to two layers despite some research prototypes having up to eight layers), as well as for recording them with Sequential Recording. However the layer jump during the recording occurs only once, at the position called Middle Area, during a Sequential Recording, while it may occur multiple times with Layer Jump Recording.
Two different Layer Jump methods are defined: Manual Layer Jump and Regular Layer Jump. The first require the software
Computer software
Computer software, or just software, is a collection of computer programs and related data that provide the instructions for telling a computer what to do and how to do it....
to specify to the hardware each jump point from layer zero to layer one (the jump from layer one to layer zero occurring always at the symmetric jump point). The latter requires the software to specify to the hardware only once the jumping interval size.
This technology was championed by Pioneer Corporation
Pioneer Corporation
is a multinational corporation that specializes in digital entertainment products, based in Kawasaki, Kanagawa, Japan. The company was founded in 1938 in Tokyo as a radio and speaker repair shop...
, optical device manufacturer among things, and introduced to the market in 2005. The physical part of the technology was first specified within DVD Forum
DVD Forum
The DVD Forum is an international organization composed of hardware, software, media and content companies that use and develop the DVD and formerly HD DVD formats...
, and then a matching device command set was introduced to the Mt Fuji specification (which eventually was replicated within the MMC specification
MultiMedia Commands
MultiMedia Commands defines a SCSI/ATA based command set for accessing multimedia features on devices capable of such functionality. T10 subcommittee is responsible for developing it as well as other SCSI command set standards.-See also:...
). Later the Layer Jump Recording impacted the UDF file system specification
Universal Disk Format
Universal Disk Format is an implementation of the specification known as ISO/IEC 13346 and ECMA-167 and 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...
.
Unlike most recording methods, Layer Jump Recording was not unanimously adopted by optical driver manufacturer. The limited backward compatibility with legacy optical devices, complexity of device firmware
Firmware
In electronic systems and computing, firmware is a term often used to denote the fixed, usually rather small, programs and/or data structures that internally control various electronic devices...
implementation, need of significant software update for support and the slightly awkward writing sequencing, slowed down the adoption. In 2006, drives supporting the Layer Jump Recording methods were released by Pioneer itself, Plextor
Plextor
is a brand best known for its optical disc recorders. The brand name is used for all products manufactured by the Electronic Equipment Division and Printing Equipment Division of Shinano Kenshi. The brand was formerly known as TEXEL by which name it introduced its first CD-ROM optical disk drive in...
, BenQ
BenQ
BenQ Corporation is a Taiwanese multi-national company that sells and markets consumer electronics, computing and communications devices under the "BenQ" brand name, which stands for the company slogan Bringing Enjoyment and Quality to life .- Company :BenQ sells and markets technology products,...
, Lite-On
Lite-On
Lite-On is a conglomerate of individual companies that primarily manufacture consumer electronics, including LEDs, semiconductors, computer chassis, monitors, motherboards, DVD & CD devices, and other electronic components...
, and Sony
Sony
, commonly referred to as Sony, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan and the world's fifth largest media conglomerate measured by revenues....
. The technology was also supported by optical drive chipsets from key manufacturer MediaTek.
The technology is supported by multiple recording software, but also not unanimously supported. Nero
Nero AG
Nero is a global computer software company headquartered in Karlsbad, Germany. It is perhaps most well-known for its burning software, Nero Burning ROM.-History:The company was founded as Ahead Software GmbH in 1995 by Richard Lesser....
, Sonic/Roxio
Sonic Solutions
Sonic Solutions, acquired by Rovi Corporation in 2010, was a computer software company headquartered in Novato, California. In addition to having a number of offices in the U.S., the company also maintained offices in Europe and Asia.-History:...
, CyberLink
CyberLink
CyberLink is a digital entertainment and multimedia products software corporation. CyberLink's 2008 revenue was $140 million with market capitalization of $420 million. Cyberlink's headquarters are based in Taipei, Taiwan with worldwide offices in Fremont, USA; Tokyo, Japan; and the Netherlands...
and Ulead Systems
Ulead Systems
Ulead Systems is a Taiwanese computer software company headquartered in Neihu district in Taipei, Taiwan. It is a subsidiary of Corel.- History :Ulead was founded on August 5, 1989 by Lotus Chen, Lewis Liaw and Way-Zen Chen...
claim support for Layer Jump Recording in their software.