HDMI: High Definition Multimedia Interface (English: High Definition Multimedia Interface, HDMI) is a digital video/audio interface technology, is a dedicated digital interface suitable for image transmission, which can simultaneously transmit audio and video signals, the highest data transmission speed It is 2.25GB/s.
Lotus head: A type of audio and video cable. The head of the connection is more like a lotus flower, so it is called "Lotus head" or "Lotus plug" (English name is RCA connector).
BNC: the full name of Bayonet Nut Connector, a connector for coaxial cable VGA: is a video transmission standard IBM introduced with the PS/2 machine in 1987, with high resolution, fast display speed, rich colors, etc. The advantages have been widely used in the field of color displays.
DVI: (Digital Visual Interface), digital video interface. It was launched in 1999 by the DDWG (Digital Display Working Group), which is composed of companies such as Silicon Image, Intel, Compaq, IBM, HP, NEC, and Fujitsu. Interface standard.
DHCP: Dynamic Host Configuration Protocol, used to dynamically assign configuration information to DNS: Domain Name System, which translates names into IP addresses in a user-friendly manner. MPEG: The MPEG standard has the following five major, MPEG-1, MPEG-2, MPEG- 4, MPEG-7 and MPEG-21 and so on. He is responsible for establishing video and audio standards for CDs, and members are technical experts in the fields of video, audio, and systems. Afterwards, they succeeded in separating the recording of sound and video from the traditional analog method, established the ISO/IEC11172 compression coding standard, and worked out the MPEG-format, so that audio-visual communication has entered the digital era. Therefore, the MPEG-X version that is currently widely referred to is the video, audio, and data compression standard issued by the ISO (International Organization for Standardization).
DCIF: We often say that 2CIF (704*288, also called Half D1) is twice the resolution in the horizontal direction than CIF (352*288) and does not change in the vertical direction. For 4:3, after the horizontal and vertical scaling process, the image will be unbalanced. Then we will be odd, even two HALFD1, after de-interlacing transform to form a D1, D1 reduced by the horizontal 3/4, vertical 2/3 reduction, converted into 528 * 384. The number of pixels of 528 * 384 happens to be CIF (352 *288) Two times the number of pixels, we call it DOUBLECIF, or DCIF for short, to distinguish it from what we often call 2CIF. Obviously, DCIF is more balanced than Half D1 in both horizontal and vertical directions, which improves the resolution in both horizontal and vertical directions. After testing a large number of video signals, based on the current video compression algorithm, DCIF (528*384) can well solve the problem of insufficient CIF clarity and too large D stream. Between 512K-bit rate, stable high-quality images can be obtained.
H.264: There are two international standardization organizations responsible for video and audio coding, and one is Video Coding Experts Group (VCEG) under the International Telecommunication Union (ITU-T), which promotes the development of video and audio coding technology. One is Moving Picture Experts Group (MPEG) under the International Standards Organization (ISO), which promotes the widespread use of video and audio codecs. After VCEG released the compression standard of H.263 in 1997, it formulated short-term development plan H.26N and long-term development plan H, H.26N developed into H.263+ and H.263++; MPEG released H.263 in VCEG. Later, the MPEG-4SP version was released. In the fourth quarter of 2001, when VCEGH was developed to TML9.0, MPEG and VCEG formed a joint video coding expert group JVT, which improved and improved the algorithm of H. VCEG released the compression standard of H.264 in May 2003. MPEG is based on the modification of the H compression algorithm by JVT, and incorporates this technical specification into the MPEG-4 standard. It is released as part 10 of MPEG-4 (PART10) and is the AVC version of MPEG-4. H.264 and MPEG-4 AVC represent the latest achievements in video and audio encoding and decoding of all humans.
H.265: H.265 is the new video coding standard developed by ITU-TVCEG following H.264. The H.265 standard revolves around the existing video coding standard H.264, retaining some of the original technologies and improving some related technologies. The new technology uses advanced techniques to improve the relationship between codestream, encoding quality, latency, and algorithm complexity to achieve optimal settings. The specific research contents include: improving compression efficiency, improving robustness and error recovery capability, reducing real-time delay, reducing channel acquisition time and random access delay, and reducing complexity. H264 can achieve standard-definition digital image transmission at speeds lower than 1 Mbps due to algorithm optimization. The H265 can implement 720P (resolution 1280*720) high-definition audio and video transmission using 1 to 2 Mbps transmission speed.
FAT32: FAT32 is a 4-byte (32-bit) file allocation table (FAT, full name is File Allocation Table, file allocation table). Each cluster in the FAT32 partition format is fixed at 4KB, which greatly reduces the waste of disk space and improves disk utilization.
HTTP: Hypertext Transfer Protocol IDE: A type of disk drive interface NFS: Network File System NTSC: A type of television system OSD: Screen display PAL: A type of television system PTZ: PTZ, lens control PPPoE: Transmission on Ethernet PPP protocol RCA: a video and audio interface (commonly known as the Lotus head)
RS-232: A 25-pin interface standard developed by EIA, also becoming EIA-232
RS-485: A 25-pin interface standard developed by EIA, also becoming EIA-232
SDK: Software Development Kit TCP: Transmission Control Protocol USB: Universal Serial Bus UTP: Unshielded Twisted Pair, Ethernet Interface herein refers <br> <br> saturation: the intensity of a color image or color purity <br> < br> alarms: alarm switch <br> <br> alarm: alarm acquisition serial <br> <br>: <br> <br> serial interface port numbers: protocol port address, an integer, for identifying a process <br> <br> contrast: screen brightness ratio <br> <br> multicast address: the address for the multicast <br> <br> composite stream: comprising compressed video and audio data streams <br > <br> loop-through output: herein refers to the inputted video signal one decoder output <br> <br>: resolvable control protocol controller <br> <br> video delay: recording reaches the set after time, the size of the extended period of time later <br> <br> client: initiating a program to communicate to the server <br> <br> brightness: the color image relative lightness or darkness of the color <br> <br> stream type: Compressed view Frequency data types, including streaming video and composite flow <br> <br> command trigger: triggered by command execution <br> <br> upload a central task: sending alarm and abnormal <br> data through the Ethernet port < br> color: color difference component <br> <br> audible warning: notifying <br> <br> video loss alarm sound by: video channel video input connector, but no video signal is received <br> <br > streaming: only the compressed data stream containing video <br> <br> resolution image: the image size and the size of the unit pixel <br> <br> gateway: two separate networks using different communication protocols used to connect the device <br> <br> bit rate: a bit rate type, max bit rate <br> <br> physical address: media access control address, MAC address, also known <br> <br> cruise: the path of movement of the camera <br > <br> motion detection: analyze whether there is a change in the video <br> <br> hovering detection: object appearing in the video surveillance area based on the matching location tracking, and with the The target's time of existence or number of presentations is recorded, and all targets whose lifetime or number of presentations are greater than the corresponding first set threshold are used as candidate targets; and the candidate target is subjected to histogram-based matching tracking. The time of existence or the number of times of the candidate of the tracked candidate is recorded, and the candidate target that has all the existing time or the number of times of display is greater than the corresponding second set threshold is used as the target.
Pre-record time: <br> <br> previously preset recording time before the start of recording: presetting coordinate <br> <br> occlusion alarm: alarm is blocked by a region covering the live <br> <br>: Hide a video area in the image SMART: English full name, Self-Monitoring, Analysis and Reporting Technology, its Chinese meaning is self-monitoring, analysis and reporting technology, the technology has been formally established in the ATA-3 standard, and all Hard disk manufacturers also provide support for it. SMART technology can monitor heads, disks, motors, circuits, etc. The monitoring software on the host computer analyzes and compares the running status, historical records, and preset security values ​​of monitored objects. When outside the safe value range, the user can be automatically warned. SMART technology can effectively predict potential hard disk failures and improve data security.
Dynamic adjustment of coding parameters: In the case of not starting or stopping video recording and network transmission, the adjusted coding parameters take effect. In a monitoring system, a static monitoring scene can be reduced in video resolution, image quality, code rate, and frame rate, so that the video can be kept at a low bit rate, and the resolution of the video can be improved when the image changes. , quality, bit rate and frame rate, to achieve high-quality video, because the above parameters can be dynamically modified, so you can keep the image continuous, no need to frequently switch files, that meet the requirements of high image quality at a critical moment, and save Hard disk space and network bandwidth.
Resolution: The types of resolution include display resolution, image resolution, and pixel resolution. Display resolution refers to the largest display area on the screen in a particular display mode, represented by horizontal and vertical pixels. Image resolution refers to the size of the digitized image, also represented by horizontal and vertical pixels. If the image resolution is greater than the display resolution, some images will not be displayed. Pixel resolution refers to the ratio of the width and length of a pixel. Different pixel aspect ratios will result in graphics distortion.
Commonly used image resolution in digital surveillance: PAL system: QCIF (174*144), CIF (352*288), 2CIF (704*288), DCIF (528*384), 4CIF (704*576). NTSC: QCIF (174*120), CIF (352*240), 2CIF (704*240), DCIF (528*320), 4CIF (704*480).
VGA monitor display resolution: 640*480, 800*600, 1024*768, etc.
Dual-stream: Refers to one video image outputting two independent code streams through a video encoder. The resolution, frame rate, and code rate of the output code stream can be set independently, and the generated two code streams can satisfy different applications. Requirements, such as one for hard disk storage and one for network transmission.
Watermarking: refers to the use of signal processing methods to embed hidden marks in digital multimedia data. Such marks are usually invisible and can only be extracted through specially designed detectors.
The definition of watermarks: The act of embedding information in a work without being perceived. The watermark system consists of an embedder and a detector. The embedder has two inputs: one is the information to be encoded as a watermark, and the other is a vector artwork to embed a watermark, the output of the watermark embedder is usually transmitted and recorded. The watermarked output from the embedder is input into the watermark detector. Most detectors will try to detect whether the watermark is present or not. If so, the watermarked information is output. The application of watermarking technology in the field of surveillance: content authentication, that is to say, the signature information is embedded in the content to be checked whether it is tampered with in the future. The content here refers to video data. The vast majority of watermark applications can also be accomplished using other techniques. However, true watermarks have three advantages over other technologies: 1. Insensitivity; 2. Watermarks do not disappear when a work is displayed; 3. Watermarks and bedding Watermarked works experience the same transformation.
Transparent channel: It is a technology that sends IP data packets directly to the serial port after they are parsed. In fact, it has played a role in extending the control distance of serial devices. Can use the IP network to control a variety of serial devices, such as control decoder, matrix, alarm host, access control, instrumentation and other serial devices. For users, only see point-to-point transmission, no need to care about the network transmission process, so called Serial transparent channel.
Fragmentation of files: A file is dispersedly recorded in discrete cluster numbers. The content of the files in these discrete clusters is called file fragmentation. When the contents of the hard disk file are repeatedly deleted and written, the file fragmentation is easy to occur, which increases the seek delay and rotation delay of the hard disk, thereby affecting the operating efficiency and service life of the hard disk. If the files are pre-defined, and each file is pre-assigned with consecutive cluster numbers, then file fragmentation can be completely avoided.
Cyclic recording and acyclic recording: Cyclical recording refers to the recording mode that automatically overwrites the original video data when the program detects that all HDD space in the HD video recorder is full, without replacing the HDD. Acyclic recording refers to the recording mode that stops recording when all hard disk space in the DVR is full. In this mode, the hard disk must be replaced or the hard disk must be processed (the video data should be backed up and formatted) before video recording can continue.
Motion detection: A technique for determining whether a video scene has changed by analyzing video images. Factors such as movement of the entities in the scene, changes in light, etc., are all considered to have changed in the scene.
Frame type: I (Intra code frame) frame is intra frame coded frame, P (Predicted frame) frame is coded frame forward predicted from I or adjacent P, and B (Bi-direction frame) frame is adjacent I, P Or P, P frame interpolation frame calculation.
Frame Rate: (Frame rate) is a measure used to measure the number of display frames. The so-called unit of measurement is frames per second (FPS) or Hertz (Hz). This word is mostly used for film and television production and electronic games.
Bit rate: and Bit rate refers to the number of bits transmitted per second. The unit is bps (Bit Per Second). The higher the bit rate is, the faster the data can be transmitted. The bit rate in the sound refers to the sampling rate that converts the digital sound from an analog format to a digital format. The higher the sampling rate is, the better the restored sound quality is. The bit rate (bit rate) principle in video is the same as that in sound, and refers to the sampling rate that is converted from an analog signal to a digital signal.
Lotus head: A type of audio and video cable. The head of the connection is more like a lotus flower, so it is called "Lotus head" or "Lotus plug" (English name is RCA connector).
BNC: the full name of Bayonet Nut Connector, a connector for coaxial cable VGA: is a video transmission standard IBM introduced with the PS/2 machine in 1987, with high resolution, fast display speed, rich colors, etc. The advantages have been widely used in the field of color displays.
DVI: (Digital Visual Interface), digital video interface. It was launched in 1999 by the DDWG (Digital Display Working Group), which is composed of companies such as Silicon Image, Intel, Compaq, IBM, HP, NEC, and Fujitsu. Interface standard.
DHCP: Dynamic Host Configuration Protocol, used to dynamically assign configuration information to DNS: Domain Name System, which translates names into IP addresses in a user-friendly manner. MPEG: The MPEG standard has the following five major, MPEG-1, MPEG-2, MPEG- 4, MPEG-7 and MPEG-21 and so on. He is responsible for establishing video and audio standards for CDs, and members are technical experts in the fields of video, audio, and systems. Afterwards, they succeeded in separating the recording of sound and video from the traditional analog method, established the ISO/IEC11172 compression coding standard, and worked out the MPEG-format, so that audio-visual communication has entered the digital era. Therefore, the MPEG-X version that is currently widely referred to is the video, audio, and data compression standard issued by the ISO (International Organization for Standardization).
DCIF: We often say that 2CIF (704*288, also called Half D1) is twice the resolution in the horizontal direction than CIF (352*288) and does not change in the vertical direction. For 4:3, after the horizontal and vertical scaling process, the image will be unbalanced. Then we will be odd, even two HALFD1, after de-interlacing transform to form a D1, D1 reduced by the horizontal 3/4, vertical 2/3 reduction, converted into 528 * 384. The number of pixels of 528 * 384 happens to be CIF (352 *288) Two times the number of pixels, we call it DOUBLECIF, or DCIF for short, to distinguish it from what we often call 2CIF. Obviously, DCIF is more balanced than Half D1 in both horizontal and vertical directions, which improves the resolution in both horizontal and vertical directions. After testing a large number of video signals, based on the current video compression algorithm, DCIF (528*384) can well solve the problem of insufficient CIF clarity and too large D stream. Between 512K-bit rate, stable high-quality images can be obtained.
H.264: There are two international standardization organizations responsible for video and audio coding, and one is Video Coding Experts Group (VCEG) under the International Telecommunication Union (ITU-T), which promotes the development of video and audio coding technology. One is Moving Picture Experts Group (MPEG) under the International Standards Organization (ISO), which promotes the widespread use of video and audio codecs. After VCEG released the compression standard of H.263 in 1997, it formulated short-term development plan H.26N and long-term development plan H, H.26N developed into H.263+ and H.263++; MPEG released H.263 in VCEG. Later, the MPEG-4SP version was released. In the fourth quarter of 2001, when VCEGH was developed to TML9.0, MPEG and VCEG formed a joint video coding expert group JVT, which improved and improved the algorithm of H. VCEG released the compression standard of H.264 in May 2003. MPEG is based on the modification of the H compression algorithm by JVT, and incorporates this technical specification into the MPEG-4 standard. It is released as part 10 of MPEG-4 (PART10) and is the AVC version of MPEG-4. H.264 and MPEG-4 AVC represent the latest achievements in video and audio encoding and decoding of all humans.
H.265: H.265 is the new video coding standard developed by ITU-TVCEG following H.264. The H.265 standard revolves around the existing video coding standard H.264, retaining some of the original technologies and improving some related technologies. The new technology uses advanced techniques to improve the relationship between codestream, encoding quality, latency, and algorithm complexity to achieve optimal settings. The specific research contents include: improving compression efficiency, improving robustness and error recovery capability, reducing real-time delay, reducing channel acquisition time and random access delay, and reducing complexity. H264 can achieve standard-definition digital image transmission at speeds lower than 1 Mbps due to algorithm optimization. The H265 can implement 720P (resolution 1280*720) high-definition audio and video transmission using 1 to 2 Mbps transmission speed.
FAT32: FAT32 is a 4-byte (32-bit) file allocation table (FAT, full name is File Allocation Table, file allocation table). Each cluster in the FAT32 partition format is fixed at 4KB, which greatly reduces the waste of disk space and improves disk utilization.
HTTP: Hypertext Transfer Protocol IDE: A type of disk drive interface NFS: Network File System NTSC: A type of television system OSD: Screen display PAL: A type of television system PTZ: PTZ, lens control PPPoE: Transmission on Ethernet PPP protocol RCA: a video and audio interface (commonly known as the Lotus head)
RS-232: A 25-pin interface standard developed by EIA, also becoming EIA-232
RS-485: A 25-pin interface standard developed by EIA, also becoming EIA-232
SDK: Software Development Kit TCP: Transmission Control Protocol USB: Universal Serial Bus UTP: Unshielded Twisted Pair, Ethernet Interface herein refers <br> <br> saturation: the intensity of a color image or color purity <br> < br> alarms: alarm switch <br> <br> alarm: alarm acquisition serial <br> <br>: <br> <br> serial interface port numbers: protocol port address, an integer, for identifying a process <br> <br> contrast: screen brightness ratio <br> <br> multicast address: the address for the multicast <br> <br> composite stream: comprising compressed video and audio data streams <br > <br> loop-through output: herein refers to the inputted video signal one decoder output <br> <br>: resolvable control protocol controller <br> <br> video delay: recording reaches the set after time, the size of the extended period of time later <br> <br> client: initiating a program to communicate to the server <br> <br> brightness: the color image relative lightness or darkness of the color <br> <br> stream type: Compressed view Frequency data types, including streaming video and composite flow <br> <br> command trigger: triggered by command execution <br> <br> upload a central task: sending alarm and abnormal <br> data through the Ethernet port < br> color: color difference component <br> <br> audible warning: notifying <br> <br> video loss alarm sound by: video channel video input connector, but no video signal is received <br> <br > streaming: only the compressed data stream containing video <br> <br> resolution image: the image size and the size of the unit pixel <br> <br> gateway: two separate networks using different communication protocols used to connect the device <br> <br> bit rate: a bit rate type, max bit rate <br> <br> physical address: media access control address, MAC address, also known <br> <br> cruise: the path of movement of the camera <br > <br> motion detection: analyze whether there is a change in the video <br> <br> hovering detection: object appearing in the video surveillance area based on the matching location tracking, and with the The target's time of existence or number of presentations is recorded, and all targets whose lifetime or number of presentations are greater than the corresponding first set threshold are used as candidate targets; and the candidate target is subjected to histogram-based matching tracking. The time of existence or the number of times of the candidate of the tracked candidate is recorded, and the candidate target that has all the existing time or the number of times of display is greater than the corresponding second set threshold is used as the target.
Pre-record time: <br> <br> previously preset recording time before the start of recording: presetting coordinate <br> <br> occlusion alarm: alarm is blocked by a region covering the live <br> <br>: Hide a video area in the image SMART: English full name, Self-Monitoring, Analysis and Reporting Technology, its Chinese meaning is self-monitoring, analysis and reporting technology, the technology has been formally established in the ATA-3 standard, and all Hard disk manufacturers also provide support for it. SMART technology can monitor heads, disks, motors, circuits, etc. The monitoring software on the host computer analyzes and compares the running status, historical records, and preset security values ​​of monitored objects. When outside the safe value range, the user can be automatically warned. SMART technology can effectively predict potential hard disk failures and improve data security.
Dynamic adjustment of coding parameters: In the case of not starting or stopping video recording and network transmission, the adjusted coding parameters take effect. In a monitoring system, a static monitoring scene can be reduced in video resolution, image quality, code rate, and frame rate, so that the video can be kept at a low bit rate, and the resolution of the video can be improved when the image changes. , quality, bit rate and frame rate, to achieve high-quality video, because the above parameters can be dynamically modified, so you can keep the image continuous, no need to frequently switch files, that meet the requirements of high image quality at a critical moment, and save Hard disk space and network bandwidth.
Resolution: The types of resolution include display resolution, image resolution, and pixel resolution. Display resolution refers to the largest display area on the screen in a particular display mode, represented by horizontal and vertical pixels. Image resolution refers to the size of the digitized image, also represented by horizontal and vertical pixels. If the image resolution is greater than the display resolution, some images will not be displayed. Pixel resolution refers to the ratio of the width and length of a pixel. Different pixel aspect ratios will result in graphics distortion.
Commonly used image resolution in digital surveillance: PAL system: QCIF (174*144), CIF (352*288), 2CIF (704*288), DCIF (528*384), 4CIF (704*576). NTSC: QCIF (174*120), CIF (352*240), 2CIF (704*240), DCIF (528*320), 4CIF (704*480).
VGA monitor display resolution: 640*480, 800*600, 1024*768, etc.
Dual-stream: Refers to one video image outputting two independent code streams through a video encoder. The resolution, frame rate, and code rate of the output code stream can be set independently, and the generated two code streams can satisfy different applications. Requirements, such as one for hard disk storage and one for network transmission.
Watermarking: refers to the use of signal processing methods to embed hidden marks in digital multimedia data. Such marks are usually invisible and can only be extracted through specially designed detectors.
The definition of watermarks: The act of embedding information in a work without being perceived. The watermark system consists of an embedder and a detector. The embedder has two inputs: one is the information to be encoded as a watermark, and the other is a vector artwork to embed a watermark, the output of the watermark embedder is usually transmitted and recorded. The watermarked output from the embedder is input into the watermark detector. Most detectors will try to detect whether the watermark is present or not. If so, the watermarked information is output. The application of watermarking technology in the field of surveillance: content authentication, that is to say, the signature information is embedded in the content to be checked whether it is tampered with in the future. The content here refers to video data. The vast majority of watermark applications can also be accomplished using other techniques. However, true watermarks have three advantages over other technologies: 1. Insensitivity; 2. Watermarks do not disappear when a work is displayed; 3. Watermarks and bedding Watermarked works experience the same transformation.
Transparent channel: It is a technology that sends IP data packets directly to the serial port after they are parsed. In fact, it has played a role in extending the control distance of serial devices. Can use the IP network to control a variety of serial devices, such as control decoder, matrix, alarm host, access control, instrumentation and other serial devices. For users, only see point-to-point transmission, no need to care about the network transmission process, so called Serial transparent channel.
Fragmentation of files: A file is dispersedly recorded in discrete cluster numbers. The content of the files in these discrete clusters is called file fragmentation. When the contents of the hard disk file are repeatedly deleted and written, the file fragmentation is easy to occur, which increases the seek delay and rotation delay of the hard disk, thereby affecting the operating efficiency and service life of the hard disk. If the files are pre-defined, and each file is pre-assigned with consecutive cluster numbers, then file fragmentation can be completely avoided.
Cyclic recording and acyclic recording: Cyclical recording refers to the recording mode that automatically overwrites the original video data when the program detects that all HDD space in the HD video recorder is full, without replacing the HDD. Acyclic recording refers to the recording mode that stops recording when all hard disk space in the DVR is full. In this mode, the hard disk must be replaced or the hard disk must be processed (the video data should be backed up and formatted) before video recording can continue.
Motion detection: A technique for determining whether a video scene has changed by analyzing video images. Factors such as movement of the entities in the scene, changes in light, etc., are all considered to have changed in the scene.
Frame type: I (Intra code frame) frame is intra frame coded frame, P (Predicted frame) frame is coded frame forward predicted from I or adjacent P, and B (Bi-direction frame) frame is adjacent I, P Or P, P frame interpolation frame calculation.
Frame Rate: (Frame rate) is a measure used to measure the number of display frames. The so-called unit of measurement is frames per second (FPS) or Hertz (Hz). This word is mostly used for film and television production and electronic games.
Bit rate: and Bit rate refers to the number of bits transmitted per second. The unit is bps (Bit Per Second). The higher the bit rate is, the faster the data can be transmitted. The bit rate in the sound refers to the sampling rate that converts the digital sound from an analog format to a digital format. The higher the sampling rate is, the better the restored sound quality is. The bit rate (bit rate) principle in video is the same as that in sound, and refers to the sampling rate that is converted from an analog signal to a digital signal.
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