For some time it seems that analogue video has seemed die in many applications when digital technologies have replaced the analog video technology. For example the trend in video surveillance systems that old legacy analogue composite video systems are replaces with digital camera interfaces that range from SDI to IP video. In normal video systems the analogue interfaces are replaced with HDMI.
It is interesting that it seems that analogue interfaces have not died completely, and in they even seem to me making comeback on some applications. Some people in the surveillance industry thought that analog CCTV would have been phased out years ago with introduction of digital cameras. Around 2007, megapixel resolution IP cameras (IPC) were gaining popularity and have been popular since. And there are also other digital systems on the field in use. There are digital systems (HD-SDI), IP camera system and analogue systems. Check video Difference between analog and IP CCTV Systems and IP Cameras vs HD-Over-Analog article to get idea of differences between analogue and digital systems.
Without going into too much of technical explanations, the two systems can be quickly defined: Analog cameras transfer the video signals in analog form (electrical signals), usually use coaxial cables for the cabling, and have the videos recorded by a DVR (Digital Video Recorder), where each single camera is directly connected to the DVR. IP cameras encode the video signal into IP packets, use the data network (LAN) for the cabling, and have the videos recorded by an NVR (Network Video Recorder) that can be connected anywhere on the network.
From analogue to digital connections
In the early days of HDTV Broadcasting, there were several different analogue video interfaces in use. Component Video (a.k.a. Y-Pb-Pr) was the de facto standard and millions of HD-Ready and HDTV sets were shipped with this analog input connection. VGA (Analog 15-Pin D-Sub) interface is often used for High Definition 480p/720p/1080i/1080p. VGA interface can also be wired as Analog 5x BNC or RCA, R/G/B/H/V.
Next was move to digital format interfaces. DVI interface was the first commonly used standard digital connection type on computer monitors. DVI interface is designed to transmit uncompressed digital video and can be configured to support multiple modes such as DVI-A (analog only), DVI-D (digital only) or DVI-I (digital and analog). Featuring support for analog connections, the DVI specification is compatible with the VGA interface. The maximum length recommended for DVI cables is not included in the specification, since it is dependent on the pixel clock frequency. In general, cable lengths up to 4.5 metres (15 ft) will work for display resolutions up to 1920 × 1200.
HDMI interface was designed for TV video connections. Nowadays nearly to all displays labeled as HDTVs have HDMI connection. HDMI (High-Definition Multimedia Interface) is a proprietary audio/video interface for transmitting uncompressed video data and compressed or uncompressed digital audio data from an HDMI-compliant source device to display device. Several versions of HDMI have been developed and deployed since initial release of the technology, but all use the same cable and 19 pin connector. HDMI can sustain full bandwidth for up to 10 meters of cable length. Special optical extender solutions exists to extend distances even farther by sending the signal over fiber optic cable.
For camera interfacing PC webcams use typically USB interface to transfer image data from camera to PC. The USB video device class (also USB video class or UVC) is a USB device class that describes devices capable of streaming video like webcams, digital camcorders, transcoders, analog video converters and still-image cameras. Webcams were among the first devices to support the UVC standard and are currently the most popular UVC devices. The USB standard supports many different video formats and different USB speeds. The USB cable length is normally maximum 5 meters. When longer distances are needed, USB repeaters and USB extenders can be used to extend USB distances up to around 20-30 meters.
All those solutions have quite limited transmission distance and need many signal wires, so they are not very practical for applications where signal needs to be transported for some longer distance from camera to display. In TV production there is often needs for easily transmitting signals considerable distances from cameras to the video mixer. In analogue standard-definition television (SDTV) era analogue composite video could be easily carry camera signals over single 75 ohm coaxial cable up to hundreds of meters with only some signal loss.
When TV broadcasting technology has been digitized, the camera links have also be converted to digital. Because the TV broadcasting infrastructure was already filled with 75 ohm cable wiring made originally for analogue signals, it was a good idea if that could be be used for digital signals as well. Serial digital interface (SDI) is a family of digital video interfaces first standardized by SMPTE (The Society of Motion Picture and Television Engineers). These standards are used for transmission of uncompressed, unencrypted digital video signals (optionally including embedded audio and time code) within television facilities. SDI interfaces can be roughly divided into three types: SD-SDI (270Mbp, SMPTE259M), HD-SDI (1.485Gbps, SMPTE292M) and 3G-SDI (2.97Gbps, SMPTE424M).
SDI and HD-SDI are usually available only in professional video equipment. The SDI standards use (one or more) coaxial cables with BNC connectors, with a nominal impedance of 75 ohms. This is the same type of cable used in analog video setups. It is possible to send 270 Mbit/s SDI over 300 meters (980 ft) without use of repeaters. Data is encoded in NRZI format, scramled and signal amplitude at the source is 800 mV (±10%) peak-to-peak. Coaxial variants of the specification range in length but are typically less than 300 meters (980 ft).
ITU-R BT.656 and SMPTE 259M define digital video interfaces used for broadcast-grade video high-definition serial digital interface (HD-SDI), It uses nominal data rate of 1.485 Gbit/s that is enough enough for 720p / 1080i uncompressed video. 3G-SDI (standardized in SMPTE 424M) consists of a single 2.970 Gbit/s serial link that is enough for 1080p. For those HD specifications run length is typically 100 meters (330 ft). There are also higher speed versions forultra high definition: 6G-SDI, 12G-SDI and 24G-SDI.
3G-SDI has been widely used in the radio and TV industry. At present, a large number of 3G-SDI series products have been introduced in the market, including SDI conversion equipment, SDI digital switching matrix equipment and SDI distributor.It is also used in security camera industry for HD security cameras.
An Internet Protocol camera, or IP camera, is a type of digital video camera that receives control data and sends image data via the Internet. They are commonly used for surveillance. Term IP camera or netcam usually applies only to those used for surveillance that can be directly accessed over a network connection. The first centralized IP camera was Axis Neteye 200, released in 1996 by Axis Communications
Nowadays IP cameras are available in many different resolutions and with different other features. Many cameras nowadays builds on the open standards of HTTP and real time streaming protocol (RTSP). This open architecture was intended to encourage third-party software manufacturers to develop compatible management and recording software. But there are also many proprietary IP camera systems that use manufacturer specific protocols and work only with viewing apps made by camera manufacturer.
IP camera has built-in video compression processor with web sever function, to compress raw video footage, then broadcast over Internet. There has been many video compression technologies in use in different IP cameras. With the birth of digital video compression H.264 standard, image quality of network transmission has a significant improvement compared to earlier technologies.
IP cameras send images digitally using the transmission and security features of the TCP/IP protocol which has several advantages compared to traditional point-to-point video connections. Advantages to this approach include:
- TCP/IP data can use the same wiring infrastructure as Ethernet LAN. By utilizing the same LAN network infrastructure, IP cameras can be deployed usually with no need for major re-cabling specifically for CCTV.
- Enables utilizing different network mediums such as wireless and fiber links seamlessly. TCP/IP data can transfer over copper Ethernet, fiber, Wi-Fi or any other suitable network
- No major interference / distortion hassle: With IP cameras, one won’t need to bother about interferences / image quality issues. Remember that in analog systems, especially when the cameras are over a few hundred meters/feet away from the DVR, interference and distortion due to electrical noises, poor quality connections, and ground loop effects.
- It is possible to implement secure data transmission through encryption and authentication methods such as WPA or WPA2, TKIP or AES
- Remote accessibility that lets users view live video from any device with sufficient access privileges
- Power arrangements: IP cameras can be mostly powered over the same network cable through POE (Power Over Ethernet) by simply connecting them to a POE-capable network switch, eliminating the need for separate source of power. Power over Ethernet (PoE) to supply power through the same Ethernet cable as the data.
- IP cameras generally have better image resolution than traditional analog CCTV camera
- IP cameras encode the video signal into IP packets, use the data network (LAN) for the cabling, and have the videos recorded by an NVR (Network Video Recorder) that can be connected anywhere on the network.
- With many IP cameras it is possible to implement two-way audio via a single network cable allows users to listen to and speak to the subject of the video
- Easy management: IP cameras can be easily managed and controlled remotely.
- Lots of extra features: New IP cameras come with a constantly-expanding list of new features and enhancements – these include video analytic and enhancement features, web interface for direct view and remote monitoring and control, automatic alert notifications via email and SMS and even internal NVR for recording of videos.
- Now we have mega-pixel IP cameras that totally outmatch any analog camera solution. The higher pixel resolution of the IP cameras means you can zoom into much more details of a scene even after it is recorded, without losing clarity.
There are also potential concerns specific to IP camera. The IP cameras usually cost somewhat more than simple traditional cameras. There is a risk that security can be compromised by insecure credential, insecure software on he camera, insecure protocols or insecure data storage (for example insecure cloud account to access camera).
When IP camera is connected correctly to Internet The authorized users can access the data from anywhere with internet connection. Especially public internet connection video can be complicated to set up and can be a potential security risk. Especially if the video is transmitted over the public internet rather than a private network or intranet, the system potentially becomes open to a wider audience including hackers. Criminals can hack into a CCTV system to disable or manipulate them or observe security measures and personnel.
Some installers also note that IP cameras can be more complicated to setup because they have more settings that needs to be set right than with simple “plug-and-play” analogue CCTV camera – most found that IP cameras tend to be more difficult to setup and the pricing never came down enough for many to justify the higher resolution. There are many standards and non-standard products, so integration of cameras to recording systems can be complicated. Troubleshooting IP cameras can be tricky and frustrating. Despite everything looking correct, it can still take some extra effort to bring IP cameras up and operational. IP cameras are embedded computers needing passwords, firmware, IP addresses, software integration, etc. As IP video matures, the technology gets easier to configure, but it is still far from “plug and play”.
In order to address issues of standardization of IP video surveillance, two industry groups were formed in 2008: the Open Network Video Interface Forum (ONVIF) and the Physical Security Interoperability Alliance (PSIA). While the PSIA was founded by 20 member companies including Honeywell, GE Security and Cisco, and ONVIF was founded by Axis Communications, Bosch and Sony, each group now has numerous members. Cameras and recording hardware operating under the same standard will be able to work with each other, as each device will be communicating in the same language.
Analogue seems to stay and evolve
It seems that analogue video systems seem to be to stay in on video surveillance applications. The traditional composite video systems are so cheap that they have not been completely phased out in less demanding applications where they are “good enough”. There are nowadays also HD-over-coaxial solutions that prevail in analog video surveillance applications. Analogue high definition video interfaces seem to be catching market on video surveillance applications. Multiple HD-over-coaxial technologies coexist, inevitably brings some confusions to end-users, security installer, security integrators.
The latest HD-over-coaxial solutions include AHD, ccHDtv, HD-CVI, HD-MDI, HD-SDI, HD-TVI, all these new technologies support high definition video transmitting over traditional coaxial cable. There are actually three competing analogue HDTV systems that carry color video signal over one 75 ohm coaxial cable: HD-CVI, HD-TVI and AHD.
One of the cited advantages of those analog systems over HD-SDI cameras (digital HD over coax security camera standard), is that RG59 coax cable can be run those analog signals longer distances than digital signals. For distance of signal transmission the analogue systems like HDCVI promises an enormous advantage over HDSDI. HDSDI can reach about 100 meters or 320 feet. Standard network cameras with Ethernet interface are typically run up to 100 meters of UTP. HDCVI can transmit up to 500 meters or 1600 feet
Why those analogue HD camera systems exist? Analogue HD CCTV cameras (several different systems) are connected to DVRs using the same type of coaxial cable as traditional analog CCTV cameras, typically RG59 or RG6 coax cable. One of the advertised advantages of analogue HD over HD-SDI cameras (another HD over coax security camera standard), is that RG59 coax cable can be run long distances without video loss.
In this case the “long distances without video loss” is without too much visual image quality loss – there will be some image quality loss over long cable run on those analogue systems, but the loss of image quality is not too noticeable. For comparison on the digital systems like HD-SDI that is widely used on TV broadcasting studios the signal either goes all the way through the cable without any loss of picture or signals does not get though at all (and somewhere in the middle there can be intermittent operation zone).
Some installers also tell the benefit that Analog cameras are fairly easy to run, sending recordings to a digital video recorder (DVR), which then converts the analog to digital and stores it. DVRs are also simple to set up and run. Since analog cameras have been around for years and because they are fairly simple to install, you may have an easier time finding an installer, as well as a vendor.
From 960H CCTV to analogue HD
When digital camera systems were entering CCTV markets, the analogue CCTV systems had also made some development over the traditional PAL/NTSC composite video. Before the HDCVI and HDTVI, as well as AHD, Sony 960H solution dominated the analog surveillance market. Each of analog high definition solution has its own format and specification, it must work with its own DVRs. The only solution that’s compatible with all formats is 960H.
960H represents the number of horizontal pixels in a video signal transmitted from a camera or received by a DVR (Digital Video Recorder). The resolution of 960H depends on whether the equipment is PAL or NTSC based: 960H represents 960 x 576 (PAL) or 960 x 480 (NTSC) pixels. 960H has a 16:9 widescreen aspect ratio.There is also related term 960P. 960P is the 960×480 “progressive scan” camera format used in surveillance cameras, action POV cams and Webcams. The 960p resolution adds a wider horizontal view than standard definition (SD) 704×480, but less than HD at 1280×720 or 1920×1080.
For comparison for traditional NTSC digitally transmitted horizontal resolution is usually 720 samples (which includes 16 samples for the horizontal sync and horizontal blanking) or 704 visible pixels with an aspect ratio of 4:3 (with vertically rectangular pixels) and therefore a display resolution of 640 × 480 (480i). For NTSC video images, the SMPTE 259M professional standard specifies that the 525 lines be represented as 720 × 486—that is, 720 horizontal pixels by 486 vertical pixels. For PAL video images, frames are always 720 × 576 pixels, regardless of video source.
720P VS 960H Comparison Demo – 720p / 960H HD-TVI Weatherproof IR Bullet Camera -TVIOB-TP1IRE-W
HDCVI ( High Definition Composite Video Interface) is a solution for megapixel high definition applications, featuring non-latent long-distance transmission at a lower cost than digital systems. This technology promises high definition video footage to be transmitted over coax cable at considerably longer distances than network based cameras. Dahua developed and promoted the high-definition composite video interface (HD-CVI) which based on megapixel CMOS image sensors with its own in-house image signal processor (ISP).
The HDCVI technology modulates the image signal then transmits by using both base-band and quadrature amplitude modulation. The name HDCVI is derived partly from the fact that it uses baseband and quadrature amplitude modulation(QAM). The baseband is used is used for black&white video, while QAM is used for color information. The carrier frequency of QAM is selected so that it does not interfere with black&white video, which allows the signal to avoid CVBS crosstalk and isolates the hue and brightness signals which significantly enhances the video quality. The technology features the Auto Signal Compensation (ASC) patent, which can compensate for signal distortion caused by long cable.
The HDCVI solution incorporates both cameras and DVRs. The system is star topology structured — the DVR serves as a node for an over coax P2P (Point-to-Point) transmission to the camera. The technology offers two specifications: 1080p (1920×1080) and 720p (1280×720). Dahua is the company HD-CVI. HD-CVI version 1.00 which specified the format: 720p (1280×720) and 1080p (1920×1080), which is similar to 700 TVL and 750 TVL. Camera types available are are sometimes referred as 1920H and 1280H which translates to 1080P and 720P respectively
HD-CVI is also designed to support a back channel allowing control information to be embedded in the vertical blanking interval for information transfer between the receiver/transmitter (control camera functions, for embedding information about the transmitter signal source or the camera environment).The vertical blank can be used two-way data communication. The end to end transmission can support features for PTZ control (cameras that support RS485 control can be used). Also cameras’ OSD menu can be accessed. The back channel also permits automatic cable equalization control also called Auto Signal Compensation or ASC. With those features HD-CVI is able to transmit video, audio and control (OSD or PTZ) over a single coaxial cable instead of requiring separate cables for each transmission. With POC (Power Over Coaxial) HDCVI adapters single coaxial cable can also carry camera power (24-36V on cable that is converted to 12V for camera).
HDCVI can you use RG6 or RG59 and not have any problems, so using standard cabling and connectors will allow for the same level of ease for installation as legacy CCTV cameras. Cable equalization is needed because the high frequencies can cause considerable loss on long cables, and the attenuation varies with frequency. For the target distance specification of 300m of RG-59 and at the highest transmitted frequency (for 720p/60Hz = 73MHz) we are therefore required to accommodate approximately 3dB/100ft, (9.8dB/100m), or 29.5dB of loss. The loss at 100kHz for a 300m cable run is 0.9dB. To improve the signal to noise ratio (SNR) of the transmission pre-emphasis is used. The degree of pre-emphasis is programmable to allow for different cable lengths (maximum pre-emphasis is set at 30dB). Chroma starts dropping first when cable lengths get longer, however automatic colour control in the receiver can maintain the colour saturation over a further 20dB signal attenuation (to approximately 500m). This automatically tuning process is called Auto Signal Compensation (ASC). Distances of greater than 300m are achievable and in excess of 500m at 720p/60Hz with some small signal degradation. As with most analogue transmission methods, the signal degradation is ‘graceful’ with no sudden cut-off. At extreme distances that are too much for the compensation system to handle the signal will revert to monochrome.
The basic concept of the HD-CVI interface is to build on the proven and reliable transport method of NTSC. NTSC transmissions are capable of being transmitted over more than 1km across RG-59 cable but the bandwidth is limited to 5MHz. NTSC also has chroma/luma crosstalk issues because of the interleaved nature of the signal that are difficult to resolve at the receiver end.
HD 720p/60Hz transmission requires a luma bandwidth of 30MHz. Because we have only a single coaxial cable for the transport we have chosen to transmit luma (30 MHz) and band-limited colour difference signal (15 MHz). The colour difference signals are modulated onto a carrier in quadrature. The carrier is set above the luma bandwidth so there is no interference between the two signals. For 720p/60Hz chroma transmission the carrier is at 58.559489MHz. The effective bandwidth of the complete signal is therefore approximately 73MHz. For digital video signal reception processing this sets the minimum sampling frequency to 146MHz.
For HD 720P/60 Hz HSync is 45kHz and VSync is 60Hz. The HD-CVI sync waveform uses conventional syncs rather than tri-level syncs that are used on some other analogue HDTV interfaces. Transmitting a peak to peak video level of 2V which maintains compatibility with any legacy SD equipment on the network and also allows common low-power 5V drivers to be used.
Because of the similarity in the transmission method to NTSC both the transmitter and receiver can easily be made to accommodate conventional NTSC/PAL transmissions. HD-CVI is also backward compatible to standard definition NTSC/PAL transmissions.
HD-TVI means High Definition Transport Video Interface. HD-TVI uses coaxial cable medium and support HD video signal (1080P/720P), Audio signal, digital signal transmission. HD-TVI was developed by USA company – Techpoint. Especially Hikvision takes advantage of HD-TVI technology in order to against Dahua HD-CVI. HD-TVI promises to combine what’s great about having an analog system (great range and low storage space), with what’s great about a digital system (better picture quality and more features).
HD-TVI is based on a DSP-TVI technology developed by Techpoint(2012), and the Chipset was sold to Intersil. Several Chinese manufacture, such as Hikvision, HanBang, put this technology into their product. HD-TVI supports 3-way cable – video, data and audio on one cable. HD-TVI transmission distance is 300m coax 3C or 500m coax 5C. Twisted pair cable (Cat 5e UTP) media is possible with balun over 200 meters.
At IFSEC 2015 London (Global security exhibition), Techpoint introduced its HD-TVI 2.0 version. HD-TVI 2.0 version supports 720p 30/25fps, 720p 60/50fps, 1080p 30/25fps high definition video transmission. Furthermore, HD-TVI receiver is back compatible with older 960H format, which means the HD-TVI DVR can receive analog signals from analog 960H video cameras.
Video: HDTVI vs HDCVI
AHD CCTV is an analog high definition closed-circuit television video surveillance standard that uses coax cable to transmit HD video from security cameras to DVR. AHD stands for analog high definition. AHD supports 720p and 1080p HD video resolutions.
AHD is based on AHD standard which developed by Korean chip-set manufacturer – NextChip. AHD is able to deliver uncompressed 720p / 1080p high definition video over Cat 75-3 coaxial cable, and transmission distance up to 500 meters. It promises to achieve low-cost, long range, no video latency, high efficient megapixel resolution video transmission. Transmitting 720P or 1080i video needs at around 37 MHz video bandwidth. RG-59 cable but this cable is limited to low frequency use (<200MHz) for most applications; (at 1GHz its attenuation is 30dB/100m).
According to cctvcamerapros.com installers can reliably use RG59 coax cable up to a max distance of 800 feet for AHD cameras (around 240 meters). AHD data transmission technology doesn’t lay a big claim on a coax cable quality. AHD cameras can also use UTP cable with video baluns to run cable up to 320 Meters / 960 feet with CAT5 cable.
AHD cameras have the largest group of manufacturers, so the competition is fierce, you can get an very cheap AHD megapixel camera. Depending on your AHD cameras: AHD cameras have total three formats; AHD 0.8, AHD 1.0, AHD 2.0. AHD 0.8 format will deliver 960H resolution (definition between 960H and 720P, max to 800TVL). AHD 1.0 can support 720p high definition (HD) video capturing and recording. AHD 2.0 can support 1080p full high definition (FHD) resolution.
If you choose AHD camera that supports AHD 0.8 for,at, then camera will deliver 960H resolution, so it works with your traditional 960H DVR. This is the reason why Nextchip claims AHD is back-compatible with conventional analog video surveillance system.
AHDL: AHD 0.8, works with 960H AHD cameras and traditional analog cameras
AHDM: AHD 1.0, works with 960P/720P/960H AHD cameras
AHDH: AHD 2.0, works with 1080P/960P/720P/960H AHD cameras
960P is the 960×480 “progressive scan” camera format used in surveillance cameras, action POV cams and Webcams. The 960p resolution adds a wider horizontal view than standard definition (SD) 704×480, but less than HD at 1280×720 or 1920×1080.
ccHDtv (High definition closed-circuit television) is a high definition video surveillance solution. CCHDTV (DTV for short) is a fully digital technology that uses digital transmission techniques to deliver digital video. It is very much like IP cameras, with the important difference that it can run not only on Ethernet cables, but also directly on old, existing coaxial cables. ccHDtv solution can support 1080p 30fps or 1080p 60fps video over a 5C2V/RG6 coaxial cable.
The core concept of ccHDtv is utilizing multiple video technologies to transmit high definition signal over coaxial cable, or even transmit wirelessly. ccHDtv is developed by iTE Tech, a Taiwanese semiconductor manufacturer. ccHDtv is digital system that utilizes DTV technologies including DVB-T, ISDB-T, and ATSC standards. Frequency division multiplexing (frequency channels) allows transmission of multiple HD or UHD (1080p30, 1080p60, 4K, and so on) digital video signals over a single coaxial cable.Setting the modulated signal at different channel (center frequency), one can combine the signals from different cameras with a simple TV combiner (splitter), so that only one coaxial cable is required.
The system uses video compression before transmission.With H.264 compression, the data rate is around 3~4Mb/s for 1080P HD video, and around 8Mb/s for 4K video. With H.265 compression the data rate is even less. The data rate of a ccHDTV channel can be up to 31.67 Mb/s, which is far more than enough for 4K video.
Comparison of different systems
What is the image quality of the different systems? How they compare to each other? AHD CAMERA: TRUTHS AND FACTS YOU MUST KNOW article gives a comparison of image quality different systems can give:
720p AHD/CVI/TVI = Sony Effio 700TVL analog cameras
960P AHD/CVI/TVI = 720p (1.0MP) Network cameras
1080P AHD/CVI/TVI = 960P – 1080P (1.3MP – 2MP) Network cameras
Keep in mind that not all resolution numbers on CCTV product might not be truthful. In order to obtain much more customers, some security camera manufacturers may use fictitious TV line specification on its products. The actual product image resolution may not reach claimed resolution (like 1000TVL, 1200TVL, or ridiculous 2000TVL).
Basically, all of these analogue HD-over-coax technologies provide the around the same performance. To most, doing a side by side comparison of HDCVI and HDTVI at their highest level of image quality just reveals that they look identical under optimal conditions. Where the image quality begins to vary is when you stray from the optimal setup. Also the pricing between HDCVI and HDTVI products is very comparable.
The main difference is what companies work with which technologies.
HD-CVI is developed by Dahua. Dahua is both the developer/creator of HDCVI and the sole manufacturer of HDCVI Digital Signal Processors (DSP) and HDCVI Digital Video Recorder (DVR) boards. To make a long story short, if you want an HDCVI DVR, the board is going to be made by Dahua.
HD-TVI is advocated by Hikvision. Hikvision partnered with Techpoint to come up with HDTVI. Hikvision has opted for a more “open source” approach. Instead of taking the sole manufacturer route of specific components, they have opted to release the information necessary for other manufacturers to produce their own variations (presumably for a price). HD-TVI is open standard, which allows many of manufacturers develop analog security cameras based on this technology. Due to the fact that HDTVI was second on the market, HDCVI is little more popular now.
AHD owned by Nextchip. AHD cameras have the largest group of manufacturers, so the competition is fierce, you can get an very cheap AHD megapixel camera. AHD is open standard, which allows many of manufacturers develop analog security cameras based on this technology.
Which standard will win? It is hard to tell. I expect that those standards will co-exist for some time and there will be products that can handle several standards at the same time. Dahua seems to be already making monitor that can handle all HD-CVI, AHD, HDTVI, CVBS 16:9.
Will HD-CVI and HDTVI completely replace 960H? The answer is no. In terms of what the 720p HD-over-coaxial solution can offer, it is indeed very similar to 960H image quality. However, 960H products still stand out since they are offered and supported by most of the current camera vendors.
Will AHD replace analog CCTV cameras? Time will tell. Traditional CCTV technology is extremely stable and prices are very affordable. The cost for HD-TVI and AHD is also extreme low, so end-users can enjoy the analog high definition video surveillance with almost the same price as traditional analog camera. I expect analog HD systems and CCTV to co-exist together for many years.
Will IP cameras replace analog systems? Should I use IP instead of analog system? I this it is generally best to use IP video surveillance system when customers want to setup a new video surveillance system especially when there is structured LAN cabling on the site. IP camera system can be considered future proof (unless you happen to get bad IP cameras).
There are few conditions when one might still justify an analog camera solution: If there is no network infrastructure available, one might still consider an analog camera solution for the sake of lower costs of implementation. It’s undeniable that analog HD-over-coaxial technologies are cheaper and able to deliver so-called “720p / 1080p” HD video, but IP camera system is future proof. In case you have an existing analog system with already installed coaxial cables that you can use, then HD-over-coaxial products can be good choices. With HD analog, like old NTSC / PAL analog, cameras are not computers and immediately connect to recorders, without needing passwords, firmware, IP addresses, software integration, etc. However, HD analog has its own limitations compared to IP (most notably in maximum resolution, advanced functionalities, breadth of support). Very small systems for small shops: If you want a very simple and cost effective setup to include up to 4 cameras connected with a very short cables to a DVR to setup a basic surveillance for a small shop, analog cameras are probably still considerable for 1-2 more years.
HD Over Coax Comparison: EX-SDI vs. HD-CVI vs. HD-TVI vs. AHD