Comparison of high definition optical disc formats
Encyclopedia
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.
Other high-definition optical disc formats were attempted, including the multi-layered red-laser Versatile Multilayer Disc
and a Chinese made format called EVD
. Both appear to have been abandoned by their respective developers.
a These maximum storage capacities apply to currently released media as of July 2008. The DVD Forum
has approved a triple-layer version of HD DVD that would have a capacity of up to 51 GB, and Hitachi
has proposed a modified Blu-ray version that would support a capacity of up to 100 GB. However, neither has yet been mass-produced or released.
b All HD DVD players are required to decode the two primary channels (left and right) of any Dolby TrueHD track; however, every Toshiba made stand alone HD DVD player released thus far decodes 5.1 channels of TrueHD.
c On November 1, 2007 Secondary video and audio decoder became mandatory for new Blu-ray Disc players when the Bonus View requirement came into effect. However, players introduced to the market before this date can continue to be sold without Bonus View.
d There are some differences in the implementation of Dolby Digital Plus (DD+) on the two formats. On Blu-ray Disc, DD+ can only be used to extend a primary Dolby Digital (DD) 5.1 audiotrack. In this method 640 kbit/s is allocated to the primary DD 5.1 audiotrack (which is independently playable on players that do not support DD+), and up to 1 Mbit/s is allocated for the DD+ extension. The DD+ extension is used to replace the rear channels of the DD track with higher fidelity versions, along with adding additional channels for 6.1/7.1 audiotracks. On HD DVD, DD+ is used to encode all channels (up to 7.1), and no legacy DD track is required since all HD DVD players are required to decode DD+.
e On PAL DVDs, 24 frame per second content is stored as 50 interlaced frames per second and gets replayed 4% faster. This process can be reversed to retrieve the original 24 frame per second content. On NTSC DVDs, 24 frame per second content is stored as 60 interlaced frames per second using a process called 3:2 pulldown, which if done properly can also be reversed.
f As of July 2008, about 66.7% of Blu-ray discs are region free and 33.3% use region codes.
g DVD supports any valid MPEG-2
refresh rate as long as it is packaged with metadata converting it to 576i50 or 480i60, This metadata takes the form of REPEAT_FIRST_FIELD instructions embedded in the MPEG-2 stream itself, and is a part of the MPEG-2 standard. HDDVD is the only high-def disk format that can decode 1080p25 and 1080p30 while Blu-ray and HDDVD can both decode 1080p24. 1080p25 and 1080p30 content can only be presented on Blu-ray as 1080i50 and 1080i60 respectfully.
h Linear PCM is the only lossless audio codec that is mandatory for both HDDVD and Blu-ray disk players, only HDDVD players are required to decode two lossless sound formats and those are Linear PCM and Dolby TrueHD. Dolby TrueHD and DTS-HD Master Audio have become sound format of choice for many studios on their Blu-ray titles but ever since Blu-ray won the format war, it has not become clear if the they are now Mandatory for all new Blu-ray disk players since the end of the format war.
approved a preliminary specification for the triple-layer 51GB HD DVD (ROM only) disc though Toshiba never stated whether it was compatible with existing HD DVD players. In September 2006 TDK
announced a prototype Blu-ray Disc with a capacity of 200GB. TDK was also the first to develop a Blu-ray prototype with a capacity of 100GB in May 2005. In October 2007 Hitachi developed a Blu-ray prototype with a capacity of 100GB. Hitachi has stated that current Blu-ray drives would only require a few firmware updates in order to play the disc.
The first 50 GB dual-layer Blu-ray Disc release was the movie Click, which was released on October 10, 2006. As of July 2008, over 95% of Blu-ray movies/games are published on 50 GB dual layer discs with the remainder on 25 GB discs. 85% of HD DVD movies are published on 30 GB dual layer discs, with the remainder on 15 GB discs.
The choice of video compression technology (codec) complicates any comparison of the formats. Blu-ray Disc and HD DVD both support the same three video compression standards: MPEG-2
, VC-1
and AVC
, each of which exhibits different bitrate/noise-ratio curves, visual impairments/artifacts, and encoder maturity. Initial Blu-ray Disc titles often used MPEG-2 video, which requires the highest average bitrate
and thus the most space, to match the picture quality of the other two video codecs. As of July 2008 over 70% of Blu-ray Disc titles have been authored with the newer compression standards: AVC and VC-1. HD DVD titles have used VC-1 and AVC almost exclusively since the format's introduction. Warner Bros., which used to release movies in both formats prior to June 1, 2007, often used the same encode (with VC-1 codec) for both Blu-ray Disc and HD DVD, with identical results. In contrast, Paramount
used different encodings: initially MPEG-2 for early Blu-ray Disc releases, VC-1 for early HD DVD releases, and eventually AVC for both formats.
Whilst the two formats support similar audio codecs, their usage varies. Most titles released on the Blu-ray format include Dolby Digital
tracks for each language in the region, a DTS-HD Master Audio
track for all 20th Century Fox
and Sony Pictures and many upcoming Universal titles, Dolby TrueHD
for Disney and Sony Pictures and some Paramount and Warner titles, and for many Blu-ray titles a Linear PCM track for the primary language. On the other hand, most titles released on the HD DVD format include Dolby Digital Plus
tracks for each language in the region, and some also include a Dolby TrueHD
track for the primary language.
Blu-ray's basic mode is known as HDMV or BDMV ("High Definition Movie Mode" or "Blu-ray Disc Movie Mode"), whilst HD DVD's is known as "Standard Content". Both offer modest upgrades from standard DVD, such as the use of more buttons on-screen, a larger colour palette, and expanded programming environment. BDMV is more powerful than Standard Content, and has been used on many Blu-ray disc titles. Standard Content has been used less on HD DVDs. HD DVD's Standard Content is a minor change from standard DVD's subpicture technology, while Blu-ray's BDMV is completely new. This makes transitioning from standard DVD to Standard Content HD DVD relatively simple -- for example, Apple's DVD Studio Pro
has supported authoring Standard Content since version 4.0.3. For more advanced interactivity Blu-ray disc supports BD-J
while HD DVD supports Advanced Content
.
ed theirs as Durabis
, which has withstood direct abrasion by steel wool
and marring with markers in tests.
HD DVD uses traditional material and has the same scratch and surface characteristics of a regular DVD. The data is at the same depth (0.6 mm) as DVD as to minimize damage from scratching. As with DVD the construction of the HD DVD allows for a second side of either HD DVD or DVD.
A study performed by Home Media Magazine (August 5, 2007) concluded that HD DVDs and Blu-ray discs are essentially equal in production cost. Quotes from several disc manufacturers for 25,000 units of HD DVDs and Blu-rays revealed a price differential of only 5-10 cents. (Lowest price: 90 cents versus 100 cents. Highest price: $1.45 versus $1.50.) Another study performed by Wesley Tech (February 9, 2007) arrived at a similar conclusion. Quotes for 10,000 discs show that a 15 gigabyte HD DVD costs $11,500 total, and 25 gigabyte Blu-ray or a 30 gigabyte HD DVD costs $13,000 total. For larger quantities of 100,000 units, the 30 gigabyte HD DVD was more expensive than the 25 gigabyte Blu-ray ($1.55 versus $1.49).
, Warner Bros.
introduced a hybrid technology, Total HD
, that would reportedly support both formats on a single disc. The new discs would overlay the Blu-ray and HD DVD layers, placing them respectively 0.1 mm and 0.5 mm beneath the surface. The Blu-ray top layer would act as a two-way mirror, reflecting just enough light for a Blu-ray reader to read and an HD DVD player to ignore. But the following September, Warner President Ron Sanders said that the technology was on hold due to Warner being the only one that would publish on it.
On January 4, 2008, Warner Bros.
announced that it would support the Blu-ray format exclusively beginning on June 1, 2008. This news, along with the end of the format war, would indicate that the hybrid discs would not be put into production.
). Other copy protection systems include:
The HD DVD specification has no region coding, so an HD DVD from anywhere in the world will work in any player. The DVD Forum's steering committee has discussed a request from Disney to add it, but many of the 20 companies on the committee actively oppose it.
Some film titles that are exclusive to Blu-ray in the United States such as Sony's xXx
, Fox's Fantastic Four: Rise of the Silver Surfer
and The Prestige
, are available on HD DVD in other countries due to different distribution agreements (in fact, The Prestige was released outside the US by once format-neutral studio Warner Bros.
Pictures). Since there is no region coding in HD DVDs, there are no restrictions playing foreign-bought HD DVDs in an HD DVD player.
DVD
A DVD is an optical disc storage media format, invented and developed by Philips, Sony, Toshiba, and Panasonic in 1995. DVDs offer higher storage capacity than Compact Discs while having the same dimensions....
standard. The two formats remained in a format war
Format war
A format war describes competition between mutually incompatible proprietary formats that compete for the same market, typically for data storage devices and recording formats for electronic media. It is often characterized by political and financial influence on content publishers by the...
until February 19, 2008 when Toshiba, HD DVD's creator, announced plans to cease development, manufacturing and marketing of HD DVD players and recorders.
Other high-definition optical disc formats were attempted, including the multi-layered red-laser Versatile Multilayer Disc
Versatile Multilayer Disc
Versatile Multilayer Disc is a high-capacity red laser optical disc technology designed by New Medium Enterprises, Inc....
and a Chinese made format called EVD
Enhanced Versatile Disc
The Enhanced Versatile Disc is an optical medium-based digital audio/video format, developed to provide a means for playing HDTV content using existing optical media. It was announced on November 18, 2003, by the People's Republic of China's Xinhua News Agency as a response to the popular...
. Both appear to have been abandoned by their respective developers.
Technical details
| Blu-ray Disc Blu-ray Disc Blu-ray Disc is an optical disc storage medium designed to supersede the DVD format. The plastic disc is 120 mm in diameter and 1.2 mm thick, the same size as DVDs and CDs. Blu-ray Discs contain 25 GB per layer, with dual layer discs being the norm for feature-length video discs... |
HD DVD HD DVD HD DVD is a discontinued high-density optical disc format for storing data and high-definition video.Supported principally by Toshiba, HD DVD was envisioned to be the successor to the standard DVD format... |
CBHD (CH-DVD CH-DVD China Blue High-Definition is a high definition optical disc format announced in September 2007 by the Optical Memory National Engineering Research Center of Tsinghua University in China. The format is a derivative of the HD DVD, a medium created by the DVD Forum designed to succeed regular DVDs... ) |
AVCHD AVCHD AVCHD is a file-based format for the digital recording and playback of high-definition video.... |
AVCREC AVCREC AVCREC is a format for recording and playback of high definition video in BDAV format using conventional DVD recordable discs as recording media... |
DVD DVD-Video DVD-Video is a consumer video format used to store digital video on DVD discs, and is currently the dominant consumer video format in Asia, North America, Europe, and Australia. Discs using the DVD-Video specification require a DVD drive and a MPEG-2 decoder... |
MUSE LD | |||
|---|---|---|---|---|---|---|---|---|---|
| Laser Laser A laser is a device that emits light through a process of optical amplification based on the stimulated emission of photons. The term "laser" originated as an acronym for Light Amplification by Stimulated Emission of Radiation... wavelength Wavelength In physics, the wavelength of a sinusoidal wave is the spatial period of the wave—the distance over which the wave's shape repeats.It is usually determined by considering the distance between consecutive corresponding points of the same phase, such as crests, troughs, or zero crossings, and is a... |
405 nm Nanometre A nanometre is a unit of length in the metric system, equal to one billionth of a metre. The name combines the SI prefix nano- with the parent unit name metre .The nanometre is often used to express dimensions on the atomic scale: the diameter... (blue-violet laser) |
650 nm (red laser) | |||||||
| Numerical aperture Numerical aperture In optics, the numerical aperture of an optical system is a dimensionless number that characterizes the range of angles over which the system can accept or emit light. By incorporating index of refraction in its definition, NA has the property that it is constant for a beam as it goes from one... |
0.85 | 0.65 | 0.6 | ||||||
| Storage capacity (single side) |
per layer/maximum | 25/50 GB | 15/30 GB | 1.4/2.6 GB (8 cm DVD), 4.7/8.5 GB (12 cm DVD) |
4.7/8.5 GB | 30 cm, 60 min per side | |||
| Maximum bitrate Bitrate In telecommunications and computing, bit rate is the number of bits that are conveyed or processed per unit of time.... |
Raw data transfer | 53.95 Mbit/s | 36.55 Mbit/s | 18 Mbit/s | 11.08 Mbit/s | ||||
| Audio+Video+Subtitles | 48.0 Mbit/s | 30.24 Mbit/s | colspan="2" | 10.08 Mbit/s | |||||
| Video | 40.0 Mbit/s | 29.4 Mbit/s | colspan="2" | 9.8 Mbit/s | |||||
| Mandatory video codec Video codec A video codec is a device or software that enables video compression and/or decompression for digital video. The compression usually employs lossy data compression. Historically, video was stored as an analog signal on magnetic tape... s |
H.264/MPEG-4 AVC H.264/MPEG-4 AVC H.264/MPEG-4 Part 10 or AVC is a standard for video compression, and is currently one of the most commonly used formats for the recording, compression, and distribution of high definition video... / VC-1 VC-1 VC-1 is the informal name of the SMPTE 421M video codec standard, which was initially developed as a proprietary video format by Microsoft before it was released as a formal SMPTE standard video format on April 3, 2006... / MPEG-2 MPEG-2 MPEG-2 is a standard for "the generic coding of moving pictures and associated audio information". It describes a combination of lossy video compression and lossy audio data compression methods which permit storage and transmission of movies using currently available storage media and transmission... |
China's AVS Audio Video Standard Audio Video Standard is a compression standard for digital audio and video, and is competing with H.264/AAC to potentially replace MPEG-2. Chinese companies own 90% of AVS patents. The audio and video files have an .avs extension as a container format.-Overview:Development of AVS was initiated by... / H.264/MPEG-4 AVC H.264/MPEG-4 AVC H.264/MPEG-4 Part 10 or AVC is a standard for video compression, and is currently one of the most commonly used formats for the recording, compression, and distribution of high definition video... / VC-1 VC-1 VC-1 is the informal name of the SMPTE 421M video codec standard, which was initially developed as a proprietary video format by Microsoft before it was released as a formal SMPTE standard video format on April 3, 2006... / MPEG-2 MPEG-2 MPEG-2 is a standard for "the generic coding of moving pictures and associated audio information". It describes a combination of lossy video compression and lossy audio data compression methods which permit storage and transmission of movies using currently available storage media and transmission... |
H.264/MPEG-4 AVC H.264/MPEG-4 AVC H.264/MPEG-4 Part 10 or AVC is a standard for video compression, and is currently one of the most commonly used formats for the recording, compression, and distribution of high definition video... |
H.264/MPEG-4 AVC H.264/MPEG-4 AVC H.264/MPEG-4 Part 10 or AVC is a standard for video compression, and is currently one of the most commonly used formats for the recording, compression, and distribution of high definition video... MPEG-2 MPEG-2 MPEG-2 is a standard for "the generic coding of moving pictures and associated audio information". It describes a combination of lossy video compression and lossy audio data compression methods which permit storage and transmission of movies using currently available storage media and transmission... |
MPEG-1 MPEG-1 MPEG-1 is a standard for lossy compression of video and audio. It is designed to compress VHS-quality raw digital video and CD audio down to 1.5 Mbit/s without excessive quality loss, making video CDs, digital cable/satellite TV and digital audio broadcasting possible.Today, MPEG-1 has become... / MPEG-2 MPEG-2 MPEG-2 is a standard for "the generic coding of moving pictures and associated audio information". It describes a combination of lossy video compression and lossy audio data compression methods which permit storage and transmission of movies using currently available storage media and transmission... |
MUSE | |||
| Audio codec Audio codec All codecs are devices or computer programs capable of coding or decoding a digital data stream or signal.The term audio codec has two meanings depending on the context:... s (maximum data rates shown) |
lossy | Dolby Digital Dolby Digital Dolby Digital is the name for audio compression technologies developed by Dolby Laboratories. It was originally called Dolby Stereo Digital until 1994. Except for Dolby TrueHD, the audio compression is lossy. The first use of Dolby Digital was to provide digital sound in cinemas from 35mm film prints... |
colspan="2" | colspan="2" | |||||
| DTS | colspan="2" | colspan="2" | |||||||
| Dolby Digital Plus Dolby Digital Plus Dolby Digital Plus is a digital audio compression scheme. It is an incompatible development of the technologies used in the earlier Dolby Digital system. E-AC-3 has a number of improvements aimed at increasing quality at a given bitrate compared with legacy Dolby Digital... |
colspan="2" | colspan="2" | |||||||
| DTS-HD High Resolution | colspan="2" | ||||||||
| lossless | Linear PCM | colspan="3" | colspan="3" | (B Mode) 2 channel PCM |
|||||
| Dolby TrueHD Dolby TrueHD Dolby TrueHD is an advanced lossless multi-channel audio codec developed by Dolby Laboratories which is intended primarily for high-definition home-entertainment equipment such as Blu-ray Disc and HD DVD. It is the successor to the AC-3 Dolby Digital surround sound codec which was used as the... |
colspan="2" | colspan="2" | |||||||
| DTS-HD Master Audio DTS-HD Master Audio DTS-HD Master Audio is a lossless audio codec created by Digital Theater System. It was previously known as DTS++. It is an extension of DTS which, when played back on devices which do not support the Master Audio or High Resolution extension, degrades to a "core" track which is lossy. DTS-HD... |
colspan="2" | ||||||||
| Secondary video decoder (PiP Picture-in-picture Picture in Picture is a feature of some television receivers and similar devices. One program is displayed on the full TV screen at the same time as one or more other programs are displayed in inset windows. Sound is usually from the main program only.Picture in Picture requires two independent... ) |
colspan="2" | ||||||||
| Secondary audio decoder | colspan="2" | ||||||||
| Interactivity | colspan="3" | ||||||||
| Internet support | colspan="4" | ||||||||
| Video resolution Image resolution Image resolution is an umbrella term that describes the detail an image holds. The term applies to raster digital images, film images, and other types of images. Higher resolution means more image detail.... (maximum) |
1920×1080 | 720×480 (NTSC NTSC NTSC, named for the National Television System Committee, is the analog television system that is used in most of North America, most of South America , Burma, South Korea, Taiwan, Japan, the Philippines, and some Pacific island nations and territories .Most countries using the NTSC standard, as... ) 720×576 (PAL PAL PAL, short for Phase Alternating Line, is an analogue television colour encoding system used in broadcast television systems in many countries. Other common analogue television systems are NTSC and SECAM. This page primarily discusses the PAL colour encoding system... ) |
1125 interlaced lines 1035 lines displayed |
||||||
| Frame rate Frame rate Frame rate is the frequency at which an imaging device produces unique consecutive images called frames. The term applies equally well to computer graphics, video cameras, film cameras, and motion capture systems... s at maximum resolution |
24p Progressive scan Progressive scanning is a way of displaying, storing, or transmitting moving images in which all the lines of each frame are drawn in sequence... , 50/60i |
24/25/30p Progressive scan Progressive scanning is a way of displaying, storing, or transmitting moving images in which all the lines of each frame are drawn in sequence... , 50/60i |
24p 24p In video technology, 24p refers to a video format that operates at 24 frames per second frame rate with progressive scanning . Originally, 24p was used in the non-linear editing of film-originated material... , 50/60i |
24/25/30p Progressive scan Progressive scanning is a way of displaying, storing, or transmitting moving images in which all the lines of each frame are drawn in sequence... 50/60i |
60i | ||||
| Digital Rights Management Digital rights management Digital rights management is a class of access control technologies that are used by hardware manufacturers, publishers, copyright holders and individuals with the intent to limit the use of digital content and devices after sale. DRM is any technology that inhibits uses of digital content that... |
AACS Advanced Access Content System The Advanced Access Content System is a standard for content distribution and digital rights management, intended to restrict access to and copying of the "next generation" of optical discs and DVDs. The specification was publicly released in April 2005 and the standard has been adopted as the... -128bit / BD+ BD+ BD+ is a component of the Blu-ray Disc Digital Rights Management system. It was developed by Cryptography Research Inc. and is based on their Self-Protecting Digital Content concept... / ROM-Mark ROM-Mark In computing, ROM Mark or BD-ROM Mark is a serialization technology designed to guard against mass production piracy or the mass duplication and sale of unauthorized copies of pre-recorded Blu-ray Discs... |
AACS Advanced Access Content System The Advanced Access Content System is a standard for content distribution and digital rights management, intended to restrict access to and copying of the "next generation" of optical discs and DVDs. The specification was publicly released in April 2005 and the standard has been adopted as the... -128bit |
AACS Advanced Access Content System The Advanced Access Content System is a standard for content distribution and digital rights management, intended to restrict access to and copying of the "next generation" of optical discs and DVDs. The specification was publicly released in April 2005 and the standard has been adopted as the... -128bit / DKAA |
None (Not intended for prerecorded content) | CSS Content Scramble System Content Scramble System is a Digital Rights Management and encryption system employed on almost all commercially produced DVD-Video discs. CSS utilizes a proprietary 40-bit stream cipher algorithm... 40-bit |
None | |||
| Region codes Regional lockout Regional lockout is the programming practice, code, chip, or physical barrier used to prevent the playing of media designed for a device from the country where it is marketed on the version of the same device marketed in another country.-Video games:... |
Three region codes | None | None | 8 regions DVD region code DVD region codes are a digital-rights management technique designed to allow film distributors to control aspects of a release, including content, release date, and price, according to the region... (6 commercial) |
None | ||||
| Hardcoating of disc Anti-scratch coating An anti-scratch or scratch-resistant coating is a film or coating that can be applied to optical surfaces, such as the faces of a lens or photographic film. The coating does not interfere with how the lenses function and does not affect vision, but creates a permanent bond with the lens that... |
colspan="5" | ||||||||
a These maximum storage capacities apply to currently released media as of July 2008. The 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...
has approved a triple-layer version of HD DVD that would have a capacity of up to 51 GB, and Hitachi
Hitachi, Ltd.
is a Japanese multinational conglomerate headquartered in Marunouchi 1-chome, Chiyoda, Tokyo, Japan. The company is the parent of the Hitachi Group as part of the larger DKB Group companies...
has proposed a modified Blu-ray version that would support a capacity of up to 100 GB. However, neither has yet been mass-produced or released.
b All HD DVD players are required to decode the two primary channels (left and right) of any Dolby TrueHD track; however, every Toshiba made stand alone HD DVD player released thus far decodes 5.1 channels of TrueHD.
c On November 1, 2007 Secondary video and audio decoder became mandatory for new Blu-ray Disc players when the Bonus View requirement came into effect. However, players introduced to the market before this date can continue to be sold without Bonus View.
d There are some differences in the implementation of Dolby Digital Plus (DD+) on the two formats. On Blu-ray Disc, DD+ can only be used to extend a primary Dolby Digital (DD) 5.1 audiotrack. In this method 640 kbit/s is allocated to the primary DD 5.1 audiotrack (which is independently playable on players that do not support DD+), and up to 1 Mbit/s is allocated for the DD+ extension. The DD+ extension is used to replace the rear channels of the DD track with higher fidelity versions, along with adding additional channels for 6.1/7.1 audiotracks. On HD DVD, DD+ is used to encode all channels (up to 7.1), and no legacy DD track is required since all HD DVD players are required to decode DD+.
e On PAL DVDs, 24 frame per second content is stored as 50 interlaced frames per second and gets replayed 4% faster. This process can be reversed to retrieve the original 24 frame per second content. On NTSC DVDs, 24 frame per second content is stored as 60 interlaced frames per second using a process called 3:2 pulldown, which if done properly can also be reversed.
f As of July 2008, about 66.7% of Blu-ray discs are region free and 33.3% use region codes.
g DVD supports any valid MPEG-2
MPEG-2
MPEG-2 is a standard for "the generic coding of moving pictures and associated audio information". It describes a combination of lossy video compression and lossy audio data compression methods which permit storage and transmission of movies using currently available storage media and transmission...
refresh rate as long as it is packaged with metadata converting it to 576i50 or 480i60, This metadata takes the form of REPEAT_FIRST_FIELD instructions embedded in the MPEG-2 stream itself, and is a part of the MPEG-2 standard. HDDVD is the only high-def disk format that can decode 1080p25 and 1080p30 while Blu-ray and HDDVD can both decode 1080p24. 1080p25 and 1080p30 content can only be presented on Blu-ray as 1080i50 and 1080i60 respectfully.
h Linear PCM is the only lossless audio codec that is mandatory for both HDDVD and Blu-ray disk players, only HDDVD players are required to decode two lossless sound formats and those are Linear PCM and Dolby TrueHD. Dolby TrueHD and DTS-HD Master Audio have become sound format of choice for many studios on their Blu-ray titles but ever since Blu-ray won the format war, it has not become clear if the they are now Mandatory for all new Blu-ray disk players since the end of the format war.
Capacity/codecs
Blu-ray Disc has a higher maximum disc capacity than HD DVD (50 GB vs. 30 GB for a double layered disc). In September 2007 the DVD ForumDVD 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...
approved a preliminary specification for the triple-layer 51GB HD DVD (ROM only) disc though Toshiba never stated whether it was compatible with existing HD DVD players. In September 2006 TDK
TDK
, formerly , is a Japanese company which manufactures electronic materials, electronic components, and recording and data-storage media, and markets them globally. Their motto is "Contribute to culture and industry through creativity"...
announced a prototype Blu-ray Disc with a capacity of 200GB. TDK was also the first to develop a Blu-ray prototype with a capacity of 100GB in May 2005. In October 2007 Hitachi developed a Blu-ray prototype with a capacity of 100GB. Hitachi has stated that current Blu-ray drives would only require a few firmware updates in order to play the disc.
The first 50 GB dual-layer Blu-ray Disc release was the movie Click, which was released on October 10, 2006. As of July 2008, over 95% of Blu-ray movies/games are published on 50 GB dual layer discs with the remainder on 25 GB discs. 85% of HD DVD movies are published on 30 GB dual layer discs, with the remainder on 15 GB discs.
The choice of video compression technology (codec) complicates any comparison of the formats. Blu-ray Disc and HD DVD both support the same three video compression standards: MPEG-2
MPEG-2
MPEG-2 is a standard for "the generic coding of moving pictures and associated audio information". It describes a combination of lossy video compression and lossy audio data compression methods which permit storage and transmission of movies using currently available storage media and transmission...
, VC-1
VC-1
VC-1 is the informal name of the SMPTE 421M video codec standard, which was initially developed as a proprietary video format by Microsoft before it was released as a formal SMPTE standard video format on April 3, 2006...
and AVC
H.264/MPEG-4 AVC
H.264/MPEG-4 Part 10 or AVC is a standard for video compression, and is currently one of the most commonly used formats for the recording, compression, and distribution of high definition video...
, each of which exhibits different bitrate/noise-ratio curves, visual impairments/artifacts, and encoder maturity. Initial Blu-ray Disc titles often used MPEG-2 video, which requires the highest average bitrate
Bitrate
In telecommunications and computing, bit rate is the number of bits that are conveyed or processed per unit of time....
and thus the most space, to match the picture quality of the other two video codecs. As of July 2008 over 70% of Blu-ray Disc titles have been authored with the newer compression standards: AVC and VC-1. HD DVD titles have used VC-1 and AVC almost exclusively since the format's introduction. Warner Bros., which used to release movies in both formats prior to June 1, 2007, often used the same encode (with VC-1 codec) for both Blu-ray Disc and HD DVD, with identical results. In contrast, Paramount
Paramount Pictures
Paramount Pictures Corporation is an American film production and distribution company, located at 5555 Melrose Avenue in Hollywood. Founded in 1912 and currently owned by media conglomerate Viacom, it is America's oldest existing film studio; it is also the last major film studio still...
used different encodings: initially MPEG-2 for early Blu-ray Disc releases, VC-1 for early HD DVD releases, and eventually AVC for both formats.
Whilst the two formats support similar audio codecs, their usage varies. Most titles released on the Blu-ray format include Dolby Digital
Dolby Digital
Dolby Digital is the name for audio compression technologies developed by Dolby Laboratories. It was originally called Dolby Stereo Digital until 1994. Except for Dolby TrueHD, the audio compression is lossy. The first use of Dolby Digital was to provide digital sound in cinemas from 35mm film prints...
tracks for each language in the region, a DTS-HD Master Audio
DTS-HD Master Audio
DTS-HD Master Audio is a lossless audio codec created by Digital Theater System. It was previously known as DTS++. It is an extension of DTS which, when played back on devices which do not support the Master Audio or High Resolution extension, degrades to a "core" track which is lossy. DTS-HD...
track for all 20th Century Fox
20th Century Fox
Twentieth Century Fox Film Corporation — also known as 20th Century Fox, or simply 20th or Fox — is one of the six major American film studios...
and Sony Pictures and many upcoming Universal titles, Dolby TrueHD
Dolby TrueHD
Dolby TrueHD is an advanced lossless multi-channel audio codec developed by Dolby Laboratories which is intended primarily for high-definition home-entertainment equipment such as Blu-ray Disc and HD DVD. It is the successor to the AC-3 Dolby Digital surround sound codec which was used as the...
for Disney and Sony Pictures and some Paramount and Warner titles, and for many Blu-ray titles a Linear PCM track for the primary language. On the other hand, most titles released on the HD DVD format include Dolby Digital Plus
Dolby Digital Plus
Dolby Digital Plus is a digital audio compression scheme. It is an incompatible development of the technologies used in the earlier Dolby Digital system. E-AC-3 has a number of improvements aimed at increasing quality at a given bitrate compared with legacy Dolby Digital...
tracks for each language in the region, and some also include a Dolby TrueHD
Dolby TrueHD
Dolby TrueHD is an advanced lossless multi-channel audio codec developed by Dolby Laboratories which is intended primarily for high-definition home-entertainment equipment such as Blu-ray Disc and HD DVD. It is the successor to the AC-3 Dolby Digital surround sound codec which was used as the...
track for the primary language.
Interactivity
Both Blu-ray Disc and HD DVD have two main options for interactivity (on-screen menus, bonus features, etc.).Blu-ray's basic mode is known as HDMV or BDMV ("High Definition Movie Mode" or "Blu-ray Disc Movie Mode"), whilst HD DVD's is known as "Standard Content". Both offer modest upgrades from standard DVD, such as the use of more buttons on-screen, a larger colour palette, and expanded programming environment. BDMV is more powerful than Standard Content, and has been used on many Blu-ray disc titles. Standard Content has been used less on HD DVDs. HD DVD's Standard Content is a minor change from standard DVD's subpicture technology, while Blu-ray's BDMV is completely new. This makes transitioning from standard DVD to Standard Content HD DVD relatively simple -- for example, Apple's DVD Studio Pro
DVD Studio Pro
DVD Studio Pro was a high-end software tool published by Apple Inc. to allow users to create DVD masters to be sent out for replication at production houses. Its tight integration with other Apple applications allows users to take Final Cut Pro and Motion projects and render them into the DVD...
has supported authoring Standard Content since version 4.0.3. For more advanced interactivity Blu-ray disc supports BD-J
BD-J
BD-J, or Blu-ray Disc Java, is a specification supporting Java ME Xlets for advanced content on Blu-ray Disc and the Packaged Media profile of Globally Executable MHP .BD-J allows bonus content on Blu-ray Disc titles to be far more sophisticated than bonus content provided by standard DVD,...
while HD DVD supports Advanced Content
Advanced Content
Advanced Content provides interactivity in the HD DVD optical disc format.Advanced Content is used to provide interactive menus and "special features" such as additional bonus/extras content and games for HD DVD...
.
Disc construction
Blu-ray Discs contain their data relatively close to the surface (less than 0.1 mm) which combined with the smaller spot size presents a problem when the surface is scratched as data would be destroyed. To overcome this, TDK, Sony, and Panasonic each have developed a proprietary scratch resistant surface coating. TDK trademarkTrademark
A trademark, trade mark, or trade-mark is a distinctive sign or indicator used by an individual, business organization, or other legal entity to identify that the products or services to consumers with which the trademark appears originate from a unique source, and to distinguish its products or...
ed theirs as Durabis
Durabis
Durabis is a brand name for a clear polymer coating developed by the TDK Corporation. The need for a protective polymer arose because the data layer on Blu-ray Discs is much closer to the surface of the disc than in other disc formats, such as HD DVD. One of its principal applications at first was...
, which has withstood direct abrasion by steel wool
Steel wool
Steel wool, also known as wire wool, is a bundle of strands of very fine soft steel filaments, used in finishing and repairing work to polish wood or metal objects, and for cleaning household cookware....
and marring with markers in tests.
HD DVD uses traditional material and has the same scratch and surface characteristics of a regular DVD. The data is at the same depth (0.6 mm) as DVD as to minimize damage from scratching. As with DVD the construction of the HD DVD allows for a second side of either HD DVD or DVD.
A study performed by Home Media Magazine (August 5, 2007) concluded that HD DVDs and Blu-ray discs are essentially equal in production cost. Quotes from several disc manufacturers for 25,000 units of HD DVDs and Blu-rays revealed a price differential of only 5-10 cents. (Lowest price: 90 cents versus 100 cents. Highest price: $1.45 versus $1.50.) Another study performed by Wesley Tech (February 9, 2007) arrived at a similar conclusion. Quotes for 10,000 discs show that a 15 gigabyte HD DVD costs $11,500 total, and 25 gigabyte Blu-ray or a 30 gigabyte HD DVD costs $13,000 total. For larger quantities of 100,000 units, the 30 gigabyte HD DVD was more expensive than the 25 gigabyte Blu-ray ($1.55 versus $1.49).
Hybrid discs
At the January 8, 2007 Consumer Electronics ShowConsumer Electronics Show
The International Consumer Electronics Show is a major technology-related trade show held each January in the Las Vegas Convention Center, Las Vegas, Nevada, United States. Not open to the public, the Consumer Electronics Association-sponsored show typically hosts previews of products and new...
, Warner Bros.
Warner Bros.
Warner Bros. Entertainment, Inc., also known as Warner Bros. Pictures or simply Warner Bros. , is an American producer of film and television entertainment.One of the major film studios, it is a subsidiary of Time Warner, with its headquarters in Burbank,...
introduced a hybrid technology, Total HD
Total Hi Def
Total Hi Def Disc, also called Total HD or THD, was a planned optical disc format that included both of the rival high-definition optical disc formats, Blu-ray Disc and HD DVD. It was officially announced January 8, 2007 at the Warner Bros. press conference held at CES 2007...
, that would reportedly support both formats on a single disc. The new discs would overlay the Blu-ray and HD DVD layers, placing them respectively 0.1 mm and 0.5 mm beneath the surface. The Blu-ray top layer would act as a two-way mirror, reflecting just enough light for a Blu-ray reader to read and an HD DVD player to ignore. But the following September, Warner President Ron Sanders said that the technology was on hold due to Warner being the only one that would publish on it.
On January 4, 2008, Warner Bros.
Warner Bros.
Warner Bros. Entertainment, Inc., also known as Warner Bros. Pictures or simply Warner Bros. , is an American producer of film and television entertainment.One of the major film studios, it is a subsidiary of Time Warner, with its headquarters in Burbank,...
announced that it would support the Blu-ray format exclusively beginning on June 1, 2008. This news, along with the end of the format war, would indicate that the hybrid discs would not be put into production.
Copy protection
The primary copy protection system used on both formats is the Advanced Access Content System (AACSAdvanced Access Content System
The Advanced Access Content System is a standard for content distribution and digital rights management, intended to restrict access to and copying of the "next generation" of optical discs and DVDs. The specification was publicly released in April 2005 and the standard has been adopted as the...
). Other copy protection systems include:
| Blu-ray Disc Blu-ray Disc Blu-ray Disc is an optical disc storage medium designed to supersede the DVD format. The plastic disc is 120 mm in diameter and 1.2 mm thick, the same size as DVDs and CDs. Blu-ray Discs contain 25 GB per layer, with dual layer discs being the norm for feature-length video discs... |
HD DVD HD DVD HD DVD is a discontinued high-density optical disc format for storing data and high-definition video.Supported principally by Toshiba, HD DVD was envisioned to be the successor to the standard DVD format... |
|---|---|
|
|
Region coding
The Blu-ray specification and all currently available players support region coding. As of July 2008 about 66.7% of Blu-ray Disc titles are region-free and 33.3% use region codes.The HD DVD specification has no region coding, so an HD DVD from anywhere in the world will work in any player. The DVD Forum's steering committee has discussed a request from Disney to add it, but many of the 20 companies on the committee actively oppose it.
Some film titles that are exclusive to Blu-ray in the United States such as Sony's xXx
XXX
XXX may refer to:* The number 30 in Roman numerals* The year 30 AD* Games of the XXX Olympiad, the 2012 Summer Olympic Games in London, England* Super Bowl XXX, held on January 28, 1996* A mark indicating "extra strong"* Alcoholic beverages...
, Fox's Fantastic Four: Rise of the Silver Surfer
Fantastic Four: Rise of the Silver Surfer
Fantastic Four: Rise of the Silver Surfer is a 2007 American superhero film, and the sequel to the 2005 film Fantastic Four. Both films are based on the Fantastic Four comic book and were directed by Tim Story...
and The Prestige
The Prestige (film)
The Prestige is a 2006 mystery thriller film written, directed and co-produced by Christopher Nolan, with a screenplay adapted from Christopher Priest's 1995 novel of the same name. The story follows Robert Angier and Alfred Borden, rival stage magicians in London at the end of the 19th century...
, are available on HD DVD in other countries due to different distribution agreements (in fact, The Prestige was released outside the US by once format-neutral studio Warner Bros.
Warner Bros.
Warner Bros. Entertainment, Inc., also known as Warner Bros. Pictures or simply Warner Bros. , is an American producer of film and television entertainment.One of the major film studios, it is a subsidiary of Time Warner, with its headquarters in Burbank,...
Pictures). Since there is no region coding in HD DVDs, there are no restrictions playing foreign-bought HD DVDs in an HD DVD player.
External links
- Blu-ray vs. HD DVD article by cdfreaks.com