Proprietary DVR
Encyclopedia
DVRs, or Digital Video Recorder
s, are devices which record video to a hard drive. The term Proprietary DVR refers to exclusive methodologies used to maintain commercial control over the DVR format and prevent third-party copying of a particular file. CCTV
systems are used for the detection and recording of crime, but the analysts and law enforcement personnel who are required to obtain and process video recorded with proprietary DVRs may face problems using the proprietary format.
Most established manufacturers will provide tools for law enforcement agencies to play and copy footage from such systems.
The opposite of proprietary DVR is standard or PC-based DVR. (Although, in fact, many proprietary DVR's are PC-based devices.)
Currently there is no standard output for the security industry to follow. Because of this, analysts are forced to obtain a compatible "player" in order to view the video. Some proprietary DVRs are delivered to the end-user in an executable player which allows for navigation. Some require the installation of the player. Others simply require a codec
to be available on the system that is playing, then it will become viewable in a common player such as Windows Media Player
.
Some proprietary DVR systems offer more than one output format, such as the native format as well as a standard format such as AVI. Some also offer a composite video output PAL
or NTSC
. Some security companies are reluctant to offer anything other than their proprietary format. Reasons cited for maintaining control over the file by making it conversion proof vary, but most companies will make "tamperproof" a sellable feature, while disregarding the work required of an analyst or court in order to present the video.
Another selling point of proprietary DVR systems is compression. Video compression removes information in exchange for a smaller file size. Increasing compression leads to the ability to store longer periods on a disk, at the expense of sacrificing some of the detail in the images. This trade-off must be considered when attempting to balance image quality and recording time in a DVR. As storage drives become cheaper and larger, compression sacrifices are improving.
A problem inherent in proprietary DVR output is accuracy. There is a good chance that the video image as viewed has an incorrect aspect ratio
and/or color information. Color may be off simply due to the calibration of the monitor being used, but often color information is not recorded accurately. It is not very common to white balance security cameras unless it is done at set up. Aspect ratios may also be recorded improperly and could actually be quite distorted. Aspect ratios on some players are sometimes user-adjustable by dragging the viewer in one direction or the other.
Contrary to attempts made by proprietary DVR developers, it is possible to change virtually any DVR image into another format, but it cannot be done through digital conversion, such as changing an MPEG-2
to AVI
. Instead it is done by intercepting the pixels sent by the proprietary DVR to the users monitor. There are a number of software available that will capture an area of a screen and generate an uncompressed file in a common format.
Gradually technology is improving and DVR systems are capable of having features that analog video could never provide. One feature is the ability to store metadata
, such as point of sale information. Another feature may be for an event (movement, panic button, door/drawer opening) to trigger a system to record at a higher resolution. Perhaps the greatest feature is the ability to navigate directly to an area of interest.
Digital video recorder
A digital video recorder , sometimes referred to by the merchandising term personal video recorder , is a consumer electronics device or application software that records video in a digital format to a disk drive, USB flash drive, SD memory card or other local or networked mass storage device...
s, are devices which record video to a hard drive. The term Proprietary DVR refers to exclusive methodologies used to maintain commercial control over the DVR format and prevent third-party copying of a particular file. CCTV
Closed-circuit television
Closed-circuit television is the use of video cameras to transmit a signal to a specific place, on a limited set of monitors....
systems are used for the detection and recording of crime, but the analysts and law enforcement personnel who are required to obtain and process video recorded with proprietary DVRs may face problems using the proprietary format.
Most established manufacturers will provide tools for law enforcement agencies to play and copy footage from such systems.
The opposite of proprietary DVR is standard or PC-based DVR. (Although, in fact, many proprietary DVR's are PC-based devices.)
Currently there is no standard output for the security industry to follow. Because of this, analysts are forced to obtain a compatible "player" in order to view the video. Some proprietary DVRs are delivered to the end-user in an executable player which allows for navigation. Some require the installation of the player. Others simply require a codec
Codec
A codec is a device or computer program capable of encoding or decoding a digital data stream or signal. The word codec is a portmanteau of "compressor-decompressor" or, more commonly, "coder-decoder"...
to be available on the system that is playing, then it will become viewable in a common player such as Windows Media Player
Windows Media Player
Windows Media Player is a media player and media library application developed by Microsoft that is used for playing audio, video and viewing images on personal computers running the Microsoft Windows operating system, as well as on Pocket PC and Windows Mobile-based devices...
.
Some proprietary DVR systems offer more than one output format, such as the native format as well as a standard format such as AVI. Some also offer a composite video output 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...
or 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...
. Some security companies are reluctant to offer anything other than their proprietary format. Reasons cited for maintaining control over the file by making it conversion proof vary, but most companies will make "tamperproof" a sellable feature, while disregarding the work required of an analyst or court in order to present the video.
Another selling point of proprietary DVR systems is compression. Video compression removes information in exchange for a smaller file size. Increasing compression leads to the ability to store longer periods on a disk, at the expense of sacrificing some of the detail in the images. This trade-off must be considered when attempting to balance image quality and recording time in a DVR. As storage drives become cheaper and larger, compression sacrifices are improving.
A problem inherent in proprietary DVR output is accuracy. There is a good chance that the video image as viewed has an incorrect aspect ratio
Aspect ratio
The aspect ratio of a shape is the ratio of its longer dimension to its shorter dimension. It may be applied to two characteristic dimensions of a three-dimensional shape, such as the ratio of the longest and shortest axis, or for symmetrical objects that are described by just two measurements,...
and/or color information. Color may be off simply due to the calibration of the monitor being used, but often color information is not recorded accurately. It is not very common to white balance security cameras unless it is done at set up. Aspect ratios may also be recorded improperly and could actually be quite distorted. Aspect ratios on some players are sometimes user-adjustable by dragging the viewer in one direction or the other.
Contrary to attempts made by proprietary DVR developers, it is possible to change virtually any DVR image into another format, but it cannot be done through digital conversion, such as changing an 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...
to AVI
Audio Video Interleave
Audio Video Interleave , known by its acronym AVI, is a multimedia container format introduced by Microsoft in November 1992 as part of its Video for Windows technology. AVI files can contain both audio and video data in a file container that allows synchronous audio-with-video playback...
. Instead it is done by intercepting the pixels sent by the proprietary DVR to the users monitor. There are a number of software available that will capture an area of a screen and generate an uncompressed file in a common format.
Gradually technology is improving and DVR systems are capable of having features that analog video could never provide. One feature is the ability to store metadata
Metadata
The term metadata is an ambiguous term which is used for two fundamentally different concepts . Although the expression "data about data" is often used, it does not apply to both in the same way. Structural metadata, the design and specification of data structures, cannot be about data, because at...
, such as point of sale information. Another feature may be for an event (movement, panic button, door/drawer opening) to trigger a system to record at a higher resolution. Perhaps the greatest feature is the ability to navigate directly to an area of interest.