High definition television has been a standard for years and as technology advances in our daily lives, surveillance cameras are following.
So What is CVI, TVI and SDI? What's the Difference?
CVI Technology - Composite Video Interface
CVI is a licensed video technology that can send 1080p video over coax further than IP cameras can.
TVI technology - Transport Video Interface
TVI is an open technology and also can send 1080p video over coax.
HD SDI - High Definition Serial Digital Interface
SDI is a digital signal carried over coax, just as digital video for IP cameras is carried over cat-5.
What's Best? What Are the Costs of Going CVI, TVI or SDI? Can I Upgrade What I have?
All of them have their pros and cons, whether it's pricing or distance, or a variety of cameras. But they all have 1 thing in common, they all can transmit video over coax at 1080p, which is transforming the CCTV world. It's begun to raise expectations of what you'll get out of usable video footage from a break-in, a hit and run, and even from seeing a shoplifter. The type of detail available from all technologies is remarkable and has come leaps and bounds over traditional analog.
Since CVI and TVI still transmit video like 1080p or 720p analog signals, those technologies have made upgrading from a traditional analog to HD simple. Many CVI DVRs and TVI DVRs can support existing analog cameras, so upgrading doesn't have to be done all at one time. You'll be able to add HD cameras to an existing DVR or upgrade an existing analog DVR to HD and keep your existing analog cameras.
HD SDI technology has begun to produce hybrid SDI/Analog DVRs. Some SDI does carry a heavier price tag than CVI and TVI since it is a true digital signal vs. analog. CVI video is typically better during daylight and can travel up to 1600ft, comparable to TVI, while SDI can go up to 490ft. As technology advances, CVI and TVI have begun to improve DVR compatibility with IP, camera varieties such as having wide dynamic range and even hidden camera options. While Dahua is the only manufacturer in the world for CVI, Hikvision has embraced TVI, each expanding and enhancing to keep up with the demands of our times.
So one last question to answer...
If TVI, CVI and SDI can Transmit in 1080p, Why Would I Choose IP Cameras?
All of the above except IP is limited to 1080p resolution. Some manufacturers are now producing IP cameras that are capable of capturing video in up to 10megapixel quality. This may seem a bit like overkill for general coverage around a house. Still, it is ideal for jewelry stores, gas stations, college campuses, and anywhere else that high quality and great detail is needed.
There is no doubt that CVI, TVI, and SDI have changed the way we see things in the surveillance world, and with how quickly advancements are being made, it's only a matter of time before more improvements hit the market.