HANA High-Definition Audio-Video Network Alliance, founded and supported by several media and electronics companies, aims to develop technology guidelines that will make it easier for consumers to enjoy high definition television across their home entertainment systems. The guidelines would allow the transfer of HD between TVs, computers and other devices without multiple connecting wires and remote controls. See also: DLNA Website: www.hanaalliance.org
Hard disk drives Hard disk drives (HDD) comprise an assembly stacking of up to 12 rigid platters coated with magnetic oxide, each capable of storing data on both sides. Each recording surface has an associated read/write head, and any one may be activated at a given instant. Disk drives give rapid access to vast amounts of data, are highly reliable as they have only two moving parts - the swinging head assembly and the spinning disk. They can be written and read millions of times. The use of disks to store audio, video and film images has changed many aspects of digital production editing and transmission. For high capacity, disks pack data very tightly indeed.
HD Short for HDTV.
HDCAM Assigned D11, this is a series of Sony VTRs based on the Betacam principles for recording HD video on a tape format which uses the same style of cassette shell as Digital Betacam, although with a different tape formulation. The technology supports 1080-line standards. HDCAM SR is further extension of Betacam recorders using mild MPEG-4 Studio Profile (SP) intra-frame compression to store full bandwidth 4:4:4 HD RGB 1080 and 720-line video offering more headroom for digital cinema users, as well as 4:2:2 Y,Pr,Pb component video for television. It offers video data rates of 440 Mb/s and 880 Mb/s, and more audio channels than other currently available. It is scalable in its pixel count (SDTV, HDTV, film- resolution data), bit depth (10- or 12-bit), and color resolution (component or RGB). The close-to-raw-state RGB material is well suited to the needs of digital cinematography as the full latitude and bandwidth of the pictures is preserved through recording. See also: 24PsF, CineAlta, D11 Website: www.sonybiz.net/hdcamsr
HDCP High-bandwidth Digital Content Protection was designed by Intel to protect digital entertainment content across DVI or HDMI interfaces. See also: HDMI Website: www.digital-cp.com
HD D5 A D5 VTR adapted to handle high definition signals. Using around 5:1 compression the signals connect via an HD-SDI link. HD D5 can be multi- format, operating at both SD and HD TV standards. It can replay 525-line D5 as well as HD D5 cassettes. Formats include 480/60I, 1080/24P, 1080/60I, 1080/50I, 1035/59.94I and 720/60P. The recorder can also slew between 24 and 25 Hz frame rates for PAL program duplication from a 1080/24P master. Cassette recording times vary according to format, the longest is 155 minutes for 1080/24P. Website: www.panasonic-broadcast.com
HD DVD Designed as the successor to the standard DVD format HD DVD can store about three times as much data as its predecessor - 15 GB single layer, 30 GB dual layer. It is often called 3x DVD as it has three times the bandwidth and storage of regular DVDs. The future for HD DVD is unclear as Blu-ray seems to have won the format war. See also: DVD, Optical disks Website: www.dvdforum.org
HDMI The High-Definition Multimedia Interface is a digital audio and video interface able to transmit uncompressed streams. It is rapidly being adopted by both consumer and professional devices - from television sets, to set-top boxes, camcorders, game consoles and HD DVD/ Blu-ray Disc players. It replaces a pile of analog connections such as SCART, composite video, as well as DVI, audio and more. The data carried on HDMI is encrypted using High-bandwidth Digital Content Protection (HDCP) digital rights management technology - meaning that the receiving end needs to be able to decrypt HDCP.
HDR, HDRI High Dynamic Range Imaging techniques allow a greater dynamic range of exposure than normally possible, with the intention of accurately representing the wide brightness range of real scenes ranging from direct sunlight to shadows. This is sometimes used with computer-generated images or photography (by taking several pictures of a scene over a range of exposure settings) and it can provide a large amount of headroom for the adjustment of images in post production.
HD ready This describes a television that can display the recognized 720 and 1080- line formats but does not include the tuner or decoder needed to receive the signals.
HD RGB This refers to HDTV signals in RGB form rather than Y,Cr,Cb form. The difference is that HD RGB is a 4:4:4 signal that can carry the full bandwidth of each of the R, G and B channels, whereas HD (TV) is normally considered to be in 4:2:2 form where the color difference signals have a more restricted bandwidth. Generally, the 4:2:2 form of HD is sufficient for many television applications and can be carried in its uncompressed form by a single HD- SDI connection. HD RGB is often used for critical keying shots for television, and for digital cinematography. The availability of a suitable VTR (HDCAM SR) makes working with the format generally more affordable.
HD-SDI See SDI
HDTV High definition television. A television format with higher definition than SDTV. While DTV at 625 or 525 lines is usually superior to PAL and NTSC, it is generally accepted that 720-line and upward is HD. This also has a picture aspect ratio of 16:9. While there are many picture HDTV formats there is a consensus that 1080 x 1920 is a practical standard for global exchange of television material - a common image format. Many productions are made in this format. See also: 24P, ATSC, Common Image Format, DVB, Table 3 H HDV High definition DV is a tape format that stores long GOP MPEG-2 encoded HD video onto DV or MiniDV tape cassettes. At its introduction in 2004, HDV represented a huge drop in price for HD camcorders. However the quality is 'prosumer' but it has opened up a new layer of operations for HD. Also the SD down converted output is better than the usual SD DV results. The use of long GOP coding impedes frame-accurate editing. See also: AVC-Intra
HE-AAC See AAC, MPEG-4
Hexadecimal A numbering system ,often referred to as 'Hex', that works to base 16 and is particularly useful as a shorthand method for describing binary numbers. Decimal 0-9 are the same as Hex, then 10 is A, 11 is B, up to 15 which is F. See also: Binary H HIPPI High performance parallel interface (ANSI X3.283-1996). Capable of transfers up to 200 MB/s (800 with the 6400 Mb/s HIPPI, a.k.a. GSN) it is targeted at high performance computing and optimized for applications involving streaming large volumes of data rather than bursty network activity. The parallel connection is limited to short distance and so Serial HIPPI is now available (a.k.a. GSN). See also: GSN Website: www.hnf.org
Holographic recording A number of holographic recording systems are emerging as new ways of storing even more data onto 12 cm optical disks. 'Holographic' implies using optical techniques to record into the depth of the media, similar to modern high capacity hard (magnetic) disk drives that record successive tracks under one another below the disk's surface. See also: HVD Website: www.inphase-technologies.com
HSDL The High Speed Data Link is typically used to move uncompressed 2K, 10- bit RGB images (as used for digital film) within a facility. The data volumes involved are very large; each image is 12 MB, and at 24 fps this data amounts to 288 MB/s. HSDL provides an efficient transport mechanism for moving and sharing data between applications. It uses two SMPTE 292M 1.485 Gb/s serial links (HD-SDI) to provide nearly 3 Gb/s bandwidth and can result in close to realtime transfers at up to 15-20 f/s for 2K. Use of the SMPTE 292M data structure means the signal can be carried by the HD-SDI infrastructure - cabling, patch panels and routers that may already be in place for HD video. Images carried on HSDL can be imported as data to a workstation fitted with dual HD-SDI making them available for film restoration, compositing, editing, and film recorders. Archiving and transporting HSDL material can be done with data tape such as DTF-2 or LTO. See also: 2K, DTF, HD-SDI, LTO
HSM Hierarchical Storage Management is a scheme responsible for the movement of files between archive and the other storage systems that make up hierarchical storage architecture. Typically there may be three layers of storage - online, near-line and offline - that make up the hierarchy that HSM manages. Managing these layers helps to run the archive and have the required speed of access to all stored material.
Hub (network) Connects many network lines together as if to make them all part of the same wire. This allows many users to communicate but, unlike a switch, only one transaction can occur at once over the whole network. See also: CSMA/CD, Switch
Huffman coding This compresses data by assigning short codes to frequently occurring long sequences and longer ones to those that are less frequent. Assignments are held in a Huffman Table. Huffman coding is lossless and is used in video compression systems where it can contribute up to a 2:1 reduction in data. See also: JPEG
HVD Holographic versatile disk - a 'CD' sized (120mm diameter) optical disc that will be capable of storing up to 1 TB. In 2007, the HVD Forum developed three HVD standards including those for a 200 GB recordable and 100 GB ROM. See also: Holographic recording Website: hvd-forum.org
Hyperstereo (Stereoscopic) Using widely spaced cameras (e.g. beyond 70mm interocular) which record more stereo effect than the eyes can see. Such a large interocular distance can produce the effect of miniaturization. Also used in order to achieve the effect of more stereo depth and less scale in a scene. For stereo effects on very long shots (e.g. landscapes) interocular camera set ups of several meters have been used (hyperstereo). One extreme example of hyperstereo is from cameras on each side of the earth to record the sun in 3D. See also: Miniaturization, Interocular
Hypostereo (Stereoscopic) Using closely spaced cameras (e.g. less than 50 mm interocular) which record less stereo effect than the eyes can see. Such a small interocular distance can produce the effect of gigantism. If standard cameras are used, the minimum interocular distance is typically limited by the thickness of the cameras so a mirror or beam splitter system is often used, enabling interoculars down to millimeters. See also: Gigantism