A digital video recorder ( DVR ) is an electronic device that records video in digital format to disk drive, USB flash drive, SD memory card, SSD or other local or mass storage device networked. The term includes set-top boxes with live recording to disks, portable media players and TV gateways with recording capabilities, and digital camcorders. Personal computers are often connected to video recording devices and used as DVRs; in such cases the application software used for video recording is an integral part of the DVR. Many DVRs are classified as consumer electronics devices; such devices may alternately referred to as personal video recorders (PVR), especially in Canada.
Video Digital video recorder
History
Hard disk-based digital video recorder
Consumer digital video recorders ReplayTV and TiVo were launched at the 1999 Consumer Electronics Exhibition in Las Vegas, Nevada. Microsoft also showed units with DVR capability, but this was not available until late 1999 for a complete DVR feature on Dish Network's DISHplayer receiver. TiVo sent their first unit on March 31, 1999. ReplayTV won the "Best of Show" award in the video category with one of Netscape's founders, Marc Andreessen as an early investor and board member, but TiVo was more commercially successful.
Legal action by media companies forces ReplayTV to remove many features such as automatic commercial leap and share recordings over the Internet, but newer devices have steadily regained these functions while adding complementary capabilities, such as recording to DVD and remote control programming and facilities using a PDA, a network PC, and a Web browser.
Unlike VCRs, hard disk-based digital video recorders make "time shifts" more convenient and also enable functions such as stopping live TV, instant replay, chasing playback (viewing recording before completion) and skipping ads during playback.
Many DVRs use the MPEG format to compress digital video. The ability to record video has become an important part of modern decoders, as TV viewers want to control their viewing experience. Because consumers have been able to unify the ever-growing amount of video content on their set-top, delivered by traditional, satellite and terrestrial cable 'broadcast' as well as IP networks, the ability to capture programming and view it whenever they want has become a necessity. -Have functions for many consumers.
Digital video recorder tied to video services
At CES 1999, Dish Network demonstrated the hardware that would later have DVR capabilities with the help of Microsoft software. which also includes WebTV Networks Internet TV. By the end of 1999 Dishplayer had full DVR capability and within a year, more than 200,000 units were sold.
In the UK, digital video recorders are often referred to as "plus boxes" (such as BSKYB's Sky and Virgin Media's V that integrate HD capabilities, and free Freesat and Freeview subscriptions). Freeview has been in the UK since the 2000s. British Sky Broadcasting markets combined receivers and popular DVRs as Sky. TiVo launched the British model in 2000, and is no longer supported, except for third-party services, and TiVo's continuation through Virgin Media in 2010. South Africa's Africa Satellite TV beamer Multichoice recently launched their DVRs available on their DStv platform. In addition to ReplayTV and TiVo, there are a number of other terrestrial digital DVR (DTT) suppliers, including Thomson, Topfield, Fusion, Pace Micro Technology, Humax, VBox Communications, AC Ryan Playon and Advanced Digital Broadcast (ADB).
Many satellite, cable and IPTV companies combine digital video recording functionality into decoders, such as with DirecTiVo, DISHPlayer/DishDVR, Scientific Atlanta Explorer 8xxx from Time Warner, Total Home DVR from AT & amp; T U-verse, Motorola DCT6412 from Comcast and more, Moxi Media Center by Digeo (available through Charter, Adelphia, Sunflower, Bend Broadband, and Comcast and other cable companies), or Sky. Astro introduced their DVR system, called Astro MAX, which was the first PVR in Malaysia but was removed two years after its introduction.
In the case of digital television, there is no encoding required in the DVR because the signal has become a encoded MPEG digital stream. The digital video recorder only saves the digital stream directly to the disc. Once the announcer engages with, and sometimes subsidizes, the DVR design may lead to features such as the ability to use interactive TV on recorded events, pre-loading programs, or directly record encrypted digital streams. However, it can also force manufacturers to implement non-skippable ads and records that automatically expire.
In the United States, the FCC has decided that from July 1, 2007, consumers will be able to buy set-top boxes from third party companies, rather than being forced to buy or rent their set-top boxes. cable companies. This decision only applies to "navigation devices," otherwise known as cable television set-tops, and not for security functions that control user access to the content of cable operators. The net overall effect on digital video recorders and related technologies may not be as substantial as standalone DVRs currently available on the open market.
In Europe Free-To-Air and Pay TV TV gateways with multiple tuners have the ability to record the entire home enabling recording of TV programs to Network Attached Storage or USB storage installed, the programs recorded are then shared on the home network to tablet, smartphone, PC, Mac, Smart TV.
Introduction to the double tuner
In 2003 many Satellite and Cable providers introduced dual-tuner digital video recorders. In the UK, BSkyB introduced their first PVR Sky with dual tuner support in 2001. This machine has two independent tuners in the same receiver. The main use for this feature is the ability to record programs directly while watching other live programs simultaneously or recording two programs simultaneously, presumably while watching previously recorded. Kogan.com introduced a dual-tuner PVR on the Australian market that allows free-to-air television to be recorded on a removable hard drive. Some dual-tuner DVRs also have the ability to produce two separate sets of televisions at the same time. PVR produced by UEC (Durban, South Africa) and used by Multichoice and Scientific Atlanta 8300DVB PVR has the ability to view two programs while recording a third using a triple tuner.
Where multiple digital sub-channels are transmitted on one RF channel, some PVRs can record two channels and view the third channel, as long as the three sub-channels are in two channels (or one).
In the United States, DVRs are used by 32 percent of all TV households in 2009, and 38 percent in 2010, with audiences between 18 and 40 years 40 percent higher in homes that own them.
Maps Digital video recorder
Type
Integrated television sets
DVRs are integrated into several television sets (TVs). This system simplifies wiring and operation because it uses a single power cord, does not have an interconnected port (eg, HDMI), and shared a common remote control. A TV with built-in DVR was introduced by LG in 2007.
VESA Compatibility
VESA-compatible DVRs are designed to fit into the VESA mounting holes (100ÃÆ'â € "100 mm) on the back of the LCD television (TV), which allows users to combine TV and DVR into integrated units.
Set-top box
Over-the-air DVR is a stand-alone set-top-box that records broadcast television programs. Some companies have launched over-the-air DVR products for the consumer market over the past few years.
Some pay-TV providers provide a set-top box that allows customers to attach their own solid-state or network-mounted hard drive or memory to record video and other media files (for example, audio and photos).
PC based
Available software and hardware that can transform personal computers running Microsoft Windows, Linux, and Mac OS X into DVRs, and is a popular choice for home theater (HTPC) home fans.
Linux
There are many free and open source DVR software applications available for Linux. For example, the TV gateway interface to the DVB tuner and provides network tuner and TV server functionality, allowing live viewing and recording over the IP network. Other examples include MythTV, Video Recorder Disk (VDR), LinuxMCE, TiVo, VBox Home TV Gateway, and Kodi (formerly XBMC).
Mac OS
Elgato created a series of digital video recording devices called EyeTV. The software that comes with each device is also called EyeTV, and is available separately for use on compatible third-party tuners from manufacturers such as Pinnacle, TerraTec, and Hauppauge.
SageTV provides DVR software for Mac but no longer sells it. Devices previously sold support the Hauppauge HVR-950, myTV.PVR and HDHomeRun devices with their DVR software. SageTV software also includes the ability to watch YouTube and other online videos with remote control.
MythTV (see above) also runs under Mac OS X, but most recording devices are currently only supported on Linux. Compiled binaries are available for MythTV front-end, allowing Mac to watch videos from (and control) MythTV servers running on Linux.
Apple provides applications in FireWire software developer tools that allow Macs with FireWire ports to record MPEG2 transport streams from FireWire-equipped cable boxes (eg: Motorola DCT62xx, including HD stream). Applications can also change the channel on the cable box via the firewire interface. Only broadcast channels can be recorded while other channels are encrypted. FireRecord (formerly iRecord) is a free scheduled recording program derived from this SDK.
Windows
There are several free digital video recording applications available for Microsoft Windows including GB-PVR, MediaPortal, and Orb (web-based remote interface).
There are also some commercial applications available including CyberLink, SageTV (which is no longer available after Google got it in June 2011), Beyond TV (which is considered to be discontinued despite official announcements from SnapStream since last update is October 2010 and they concentrate on their company's search product ), DVBViewer, Showshifter, InterVideo WinDVR, R5000-HD and Meedio (now the product is dead - Yahoo buys most of the company's technology and stops the Meedio line, and renames the Yahoo! Go-TV software, which is now a free product but only works in US). Most TV tuner cards come with software that allows PCs to record television to hard disks. See TV tuner card. For example, Leadtek's WinFast DTV1000 digital TV card comes with WinFast PVR2 software, which can also record analog video from a composite video input card socket.
Windows Media Center is a DVR software by Microsoft that is bundled with Media Center editions of Windows XP, Home Premium/Ultimate editions of Windows Vista, and most editions of Windows 7. When Windows 8 is released in 2012, Windows Media Center is not included with Windows 8 installation OEM or Retail, and is only available as an additional $ 15 package (including DVD Playback codec) to Windows 8 Pro users.
Embedded
An embeddable DVR is a standalone tool designed to be easily integrated into more complex systems. This is usually provided as a compact and empty circuit board that facilitates installation as a component subsystem in larger equipment. The control knob is usually connected with a removable cable, to allow it to be placed outside the system while the DVR circuit is inside the equipment.
Video source
Television and video are terms that are sometimes used interchangeably, but differ in their technical sense. Video is a visual part of television, while television is a combination of video and audio that is modulated to the carrier frequency (ie television channel) for delivery. Most DVRs can record video and audio.
Analog source
The first digital video recorder is designed to record analog television in NTSC, PAL or SECAM formats.
To record an analog signal takes several steps. In the case of television signals, the tuner television must first demodulate the radio frequency signal to produce the baseband video. The video is then converted to digital form by frame grabber, which converts each video image into a collection of numeric values ​​that represent pixels in the image. At the same time, audio is also converted to digital form by analog-to-digital converter running at a constant sampling rate. In many devices, the resulting digital video and audio are compressed before recording to reduce the amount of data to be recorded, although some DVRs record uncompressed data. When compression is used, videos are usually compressed using formats like H.264 or MPEG-2, and audio is compressed using AAC or MP3.
Copy protection of analog broadcast
Many consumer DVRs implement a copy-protection system called Copy Generation Management System (Analog ) (CGMS-A), which specifies one of four possible permissions to copy by using two bits encoded in VBI:
- Copying is allowed freely
- Copying is forbidden
- Only one copy of this material can be created
- This is a copy of the material that only one copy is allowed to create, so no further copies are allowed.
CGMS-A information can be present in analog TV broadcast signals, and stored when the signal is recorded and played back by an analog VCR. VCRs do not understand the meaning of bits but take care of them if there is further effort to copy the recording to the DVR.
DVRs such as TiVo also detect and act on analog protection systems such as Macrovision and DCS Copy Protection which were originally designed to block copying on analogue VCRs.
Digital sources
Digital signal recording is generally a direct retrieval of received MPEG binary data. No expensive hardware is needed to measure and suppress the signal (because the television broadcaster has done this in the studio).
DVD-based PVRs that were available in the market in 2006 were unable to capture the full range of available visual signals with high definition television (HDTV). This is largely because the HDTV standard was resolved at a later time rather than the standard for DVD. However, DVD-based PVR can still be used (albeit with low visual quality) with HDTV because the currently available HDTV sets also have standard A/V connections.
ATSC Broadcast
ATSC television broadcasting is mainly used in North America. ATSC data streams can be recorded directly by digital video recorders, although many DVRs record only a portion of this information (which can later be transferred to DVD). The ATSC DVR will also act as a set-top box, allowing older televisions or monitors to receive digital television.
Copy Protection
The US FCC seeks to limit DVR capabilities to its "broadcast flag" rules. Digital video recorders who have not won prior approval from the FCC to implement "effective" digital rights management will be banned from interstate commerce from July 2005, but the regulation was beaten on May 6, 2005.
DVB
Digital television DVBs contain audio/visual signals broadcast in the air in digital format rather than analog. DVB data stream can be recorded live by DVR. Autonomous devices (these, which can be used without a computer/tablet) that can be stored in an external hard disk drive are called telememory.
Digital cable and satellite television
Recording satellite or digital cable signals on a digital video recorder can be more complicated than recording analog signals or broadcasting digital signals. There are several different transmission schemes, and video streams can be encrypted to restrict access to subscribers only.
A satellite or cable set-top box both decrypt the signal if it is encrypted, and it translates the stream of MPEG into an analog signal for viewing on television. To record a cable or satellite digital signal, the signal must be captured after being decrypted but before it is decoded; this is how the DVR is built into the set-top box works.
Cable and satellite providers often offer their own digital video recorder along with service plans. This DVR has access to an encrypted video stream, and generally enforces provider restrictions on copying material even after recording.
DVD
Many DVD-based DVRs have the ability to copy content from a DVD source (ripping). In the United States, this is prohibited under the Digital Millennium Copyright Act if the disk is encrypted. Most DVRs thus will not allow video stream recording from encrypted movie disks.
Digital camcorder
Digital camcorders combine digital cameras and video recorders.
Some DVD-based DVRs incorporate a connector that can be used to capture digital video from a camcorder. Some of the resulting DVD edits are usually possible, such as adding chapter points.
Some digital video recorders can now record to solid state flash memory cards (called flash camcorders ). They generally use Secure Digital cards, can include wireless connections (Bluetooth and Wi-Fi), and can play SWF files. There are some digital video recorders that combine real time video and graphics into flash cards, called DTE or "instantly edited". This is used to speed up the editing workflow in video and television production, since linear videotapes do not need to be moved to the editing workstation (see non-linear editing system).
File format, resolution and file system
DVRs can usually record and play H.264, MPEG-4 Part 2, MPEG-2.mpg, MPEG-2.TS, VOB and ISO video, with MP3 and AC3 audio tracks. They can also display images (JPEG and PNG) and play music files (MP3 and Ogg).
Some devices can be updated to play and recorded in the new format. DVRs usually record in proprietary file systems for copy protection, although some can use the FAT file system. Records from standard definition television typically have 480p/i/576p/i while HDTV is usually in 720p/1080i.
Apps
Security
Digital video recorders configured for physical security applications record video signals from closed-circuit television cameras for documentation and detection purposes. Many are designed to record audio as well. DVRs have evolved into feature-rich devices and deliver services that transcend simple video image recording previously done via VCRs. The CCTV DVR system provides many advanced functions on VCR technology including video search based on events, time, date and camera. There is also greater control over quality and frame rates that allow the use of disk space to be optimized and DVRs can also be set to overwrite the oldest security recordings if the disk becomes full. In some security systems DVR remote access to a security record using a PC can also be achieved by connecting the DVR to a LAN or Internet network. Some of the latest professional digital video recorders include video analytics firmware, to enable functions such as 'virtual tripwire' or even the detection of objects left on the scene.
DVR Security can be categorized as PC-based or embedded. The PC-based DVR architecture is a classic personal computer with video capture cards designed to capture video images. Embedded type DVRs are specifically designed as digital video recorders with operating systems and application software contained in firmware or read-only memory.
Hardware features
The hardware features of the DVR security vary between manufacturers and may include but are not limited to:
- Designed for shelf installation or desktop configuration.
- Single or dual video input with connector type consistent with analog or digital video provided such as coaxial cable, twisted pair or fiber optic cable. The most common input numbers are 1, 2, 4, 8, 16, and 32. The system can be configured with an enormous amount of input with the network or bussing individual DVRs together.
- Looping the video output for each input that duplicates the video input signal and the corresponding connector type. This output signal is used by other video equipment such as matrix switcher, multiplexer, and video monitor.
- Controlled output to an external video display monitor.
- Front panel switches and indicators that enable machine features to be controlled.
- The network connection is consistent with the network type and is used to control the recording feature and send and/or receive video signals.
- Connections to external control devices such as keyboards.
- A connection to an external pan-tilt-zoom drive positioning the camera.
- The CD, DVD, internal VCR devices are usually for archiving videos.
- Connection to external storage media.
- Enter alarm activity from external security detection devices, usually one per video input.
- Alarm events are excluded from internal detection features such as motion detection or video loss.
Software features
Software features vary between manufacturers and may include but are not limited to:
- The user-selectable shooting rate either on all input or input bases based on input. The retrieval feature can be programmed to automatically adjust the retrieval rate for external alarms or internal events
- The image resolution can be selected either on all basic input or input based on input. The image resolution feature can be programmed to automatically adjust image resolution on occurrence of external alarm or internal ventilation.
- The compression method determines the quality of playback. H.264 hardware compression offers fast transfer speed over the Internet with high quality video.
- Motion detection: Provided on input based inputs, this feature detects motion in the total image or portion of the image that the user can specify and usually provides sensitivity settings. Detection causes internal events that can be ejected to external equipment and/or used to trigger changes to other internal features.
- Lack of motion detection. Given on input based inputs, this feature detects the movement of objects into the display field and remains for a given time. Detection causes internal events that can be ejected to external equipment and/or used to trigger changes to other internal features.
- Direction of motion detection. Given on inputs based on input, this feature detects the direction of movement in a user-defined image as an unacceptable event. Detection causes internal events that can be ejected to external equipment and/or used to trigger changes to other internal features.
- Route video input to a video monitor based on user input or automatically on an alarm or event.
- Input, stamping time and date.
- Recording alarms and events on the appropriate video input.
- Search alarms and events.
- One or more voice recording channels.
- Archive.
Privacy issues
Some (very few), but of course not all, digital video recorders designed to send information to service providers over phone lines or the Internet (or any other means) can collect and send real-time data on user viewing habits.
TV Ads
Digital video recorders also change the way television programs advertise products. Watching previously recorded programs allows users to fast forward through ads, and some technologies allow users to remove ads completely. Half of the viewers in the United States, for example, use a DVR to skip the ad entirely. This feature has been controversial over the last decade, with major television networks and movie studios claiming it infringes copyright and should be banned.
In 1985, an employee of the Honeywell Physical Science Center, David Rafner, first described a drive-based DVR designed for home TV recording, time-slipping, and commercial skipping. US Patent 4,972,396 focuses on multi-channel design to allow simultaneous independent recording and playback. Broadly anticipating the development of future DVRs, it illustrates possible applications such as streaming compression, editing, captioning, multi-channel security monitoring, military sensor platforms and remotely driven vehicles.
The first DVR to feature built-in commercial skipping was introduced in 1999 by ReplayTV at the Consumer Electronics Show in Las Vegas. In 2002, five ReplayTV DVR owners sued major television networks and movie studios, asking federal judges to enforce consumer rights to record TV shows and skip advertisements, claiming that features such as commercial skipping helped parents protect their children from excessive consumerism.. ReplayTV was purchased by SONICblue in 2001 and in March 2003, SONICblue filed for Chapter 11 bankruptcy following a copyright infringement lawsuit over ReplayTV's ability to skip advertisements. In 2007, DirecTV purchased the remaining ReplayTV assets. Third party add-ons for Windows Media Center called "DVRMSToolbox" have the ability to skip advertisements. There is a command line program called Comskip that detects ads in MPEG-2 files and stores its position to a text file. This file can then be fed to a program such as MEncoder to completely remove the ad.
Many speculate that television ads will be eliminated altogether, replaced by advertisements on the TV show itself. For example, Extreme Makeover: Home Edition advertises Sears, Kenmore, Kohler, and Home Depot by specifically using products from these companies, and some sporting events like the NASCAR Sprint Cup are named after the sponsor.
The other types of ads that show more and more, mostly for TV show ads on the same channel, are where ads coat the bottom of the TV screen, blocking some images. "Banners", or "logo bugs", as they are called, are referred by media companies as Secondary Events (2E). This is done in the same way as a bad weather warning is done. Sometimes, this only takes 5-10% of the screen, but in extreme, it can take as much as 25% of the viewing area. Some even make a sound or move across the screen. One example is a 2E ad for Three Moons Over Milford in the month before its premiere. A video taking about 25% of the bottom left of the screen will show a comet impacting on the moon with an accompanying explosion, during another television program.
Due to this new widely used technology, advertisers are now looking for new ways to market their products on television. An excerpt from the Advertising Age magazine reads: "Since advertisers lose the ability to attack homes, and the minds of consumers, they will be forced to wait for invitations.This means that they must learn what type of content ad customers will actually be willing to seek and receive. "
With ads skipped and the nature of ads sensitive to specific times, advertisers are cautious in buying commercial time on digitally recorded events. However, today's technology allows the network to dynamically insert ads on videos played on DVRs. Advertisers can insert time-relevant ads to the programs recorded when the program is viewed. In this way, advertising is not only topical but also personalized for the interest of the audience. DirecTV in March 2011 entered into an agreement with NDS Group to enable the delivery of addressable ads. It is believed that viewers prefer to forward ads, rather than changing channels. By switching channels, viewers will have the possibility to skip the start of their program. Users may switch to a channel that also shows ads. Having the ability to pause, rewind, and forward live TV gives the user a chance to change fewer channels. Forwarding an ad can impact an audience later. Ads that attract viewers 'attention will influence viewers' to step back and watch what's missing.
In January 2012, Dish Network announced the Hopper service, an additional cost of $ 10 per month, which records prime-time programming from four major broadcast networks. With Auto Hop feature, viewers can watch the program they choose without ads, without trying to fast forward. On May 24, 2012, Dish and the network filed a lawsuit in federal court.
Patent and copyright litigation
On July 14, 2005, Forgent Networks filed a lawsuit against various companies claiming infringement on the US. Patent 6,285,746 , titled "Computer-controlled video system that allows playback during recording". Registered companies include EchoStar, DirecTV, Charter Communications, Cox Communications, Comcast, Time Warner, and Cable One.
Scientific-Atlanta and Motorola, equipment manufacturers sold by the above-mentioned company, filed a counter-claim against Forgent Networks claiming that their product did not infringe the patent, and that the patent was invalid. Both cases were incorporated into the case of 6: 06-cv-208, filed in the United States District Court for the Eastern District of Texas, Tyler Division.
According to court documents, on June 20, 2006, Motorola requested that the United States Patent and Trademark Office re-examine the patent, which was first filed in 1991, but has undergone several changes.
On March 23, 2007, Cablevision Systems Corp. lost a legal battle against several Hollywood studios and television networks to introduce a network-based digital video recorder service to its customers. However, on August 4, 2008, Cablevision won the appeal. John M. Walker Jr., a judge of the Second Circuit, stated that technology "will not directly infringe" the rights of media companies. Appeal to the Supreme Court rejected.
In court, media companies argue that digital video-network recorders are the same as video-on-demand, and that they should receive license fees for recording. Cablevision and the appeals court did not agree. The company notes that each user will record the program in each server room, making it a DVR that has "very long cables."
In 2004, TiVo sued EchoStar Corp., a manufacturer of DVR units, for patent infringement. The parties reached a settlement in 2011 in which EchoStar pays a one-time fee (in three structured payments) which grants full lifetime Echostar rights to the disputed TiVo patent after the first payment (as opposed to unlimited license fees and continuously increased renegotiation ), and Echostar grants TiVo the full lifetime rights to a particular Echostar patent and drops their lawsuit against TiVo.
In January 2012, AT & T resolved a similar lawsuit filed by TiVo claiming a patent infringement (such as Echostar) in exchange for a cash payment to TiVo of $ 215 million until June 2018 plus an "annual recurring fee per month subscription" to TiVo until July 2018 , but does not grant full lifetime rights as per Echostar settlement.
In May 2012, Fox Broadcasting sued Dish Network, arguing that Dish's set-top box with DVR functionality, which allows users to automatically record prime-time programs and skip advertisements, is a copyright infringement and contract violation. In July 2013, the 9th circuit rejected Fox's claim.
See also
Note
References
- Free-to-Air Television and Other PVR Challenges in Europe, technical reports from the European broadcasting union
External links
- How DVR works
- The FLOSS PVR Media Center Comparison Chart
- Commercial ads cost $ 8 billion in TV commercials this year?
- Automatic Commercial Leap in Media Center
- Television Remix: Controversy on Ad-Release
- NorDig PVR Metadata Whitepaper
- ETSI Technical Specifications TS 102 323 V1.5.1 (2012-01)
Source of the article : Wikipedia
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