Key Technological Advances in IP Camera Systems
Advances in Image Quality, High Resolution Sensors, and Low-Light Performance
Surveillance camera technology has changed quite a lot since the 1940s, when they were first introduced. The first cameras were analog systems that used cathode ray and vidicon tubes to capture an image. With the introduction of solid-state circuits and sensors, surveillance cameras became significantly more powerful and effective.
This article describes the evolution of IP Camera Systems and how it has increased security and safety.
Early CCTV Camera Systems
Surveillance cameras were developed in the 1940s, with the introduction of closed-circuit TV systems from Siemens AG, Germany (1942), Vericon (a US manufacturer active in the late 1940s), and General Precision Labs (the first major US manufacturer, active between the 1950s and 1970s).
These early systems utilized technology developed for broadcast TV, but instead of broadcasting to a large audience, they were designed for closed-circuit TV applications (CCTV). The analog signals were transferred over coax cables. They were challenging to install and set up.
The resolution was limited to 480 lines. Early TV systems specified resolution in TV lines; the frame rate was locked to the 60Hz power line frequency. A security person had to watch the video in real time, because there was no video recording. The first video cassette recorders (VCRs) were introduced in the 1970s. To learn more, see our article, The History of Video Surveillance.
Watch our video “How the Video Camera Works“ to learn more about the history of surveillance cameras.
IP Camera Systems are Introduced
The introduction of network-attached IP cameras was a significant technological change for the CCTV industry. The new digital technology enabled camera manufacturers to break free from the analog restrictions defined by NTSC and PAL specifications.
Axis introduced the first IP cameras in 1996. These new cameras were connected to the Ethernet network for communication rather than a coax cable. Video signals were now sent as digitally encoded signals instead of analog signals. See our article How the IP Camera Works to learn more.
Advances in Resolution
IP Cameras provided higher resolution. One of the first megapixel IP cameras was introduced in 2002 by IQinvision. These 1.3 megapixel (1280 x 1024 pixels) cameras provided over four times the resolution of the older VGA cameras. Other companies, such as Arecont Vision, introduced 2-megapixel cameras in 2004. The high resolution of the IP camera provided a dramatic improvement over the older analog camera technology.
The increase in sensor resolution and the availability of high-performance lenses have spurred the improvement in camera resolution.
From the early 1.3 Megapixel sensors that provided 1280 x 1024 resolution, the sensors have grown to over 32 megapixels (7680 x 4320).
The definition of resolution has evolved over the years, shifting from TV lines and sensor pixels to 4K and 8K descriptions, which are roughly associated with the horizontal pixel count. For example, a camera with a 7680 x 4320 pixel resolution is referred to as an 8K camera. Hanwha and Axis are examples of manufacturers with 8K.
Higher resolution lenses also made a significant difference in camera resolution. The resolution of the lens is measured in line pairs per millimeter. The lens should have roughly double the resolution of the camera sensor.
As the camera sensors got better, the lens manufacturers that specialized in high-resolution lenses for industrial machine vision realized that there was a new market for their high-performance lenses.
Today, instead of selling the lenses separately, the camera manufacturers include them with their cameras.
Why is resolution important? These higher resolution cameras enabled surveillance systems to see wider areas and improved their capability to identify people further away.
Advances in Low-Light Performance
Better sensor design, image processing, and lower f-stop lenses have improved the low-light capability of IP surveillance cameras.
The increased size of the sensors has contributed to improved low-light performance. For example, the Hanwha very low-light series of IP cameras includes ½ “ sensors that can capture much more light than the older ¼” sensors.
The computer chips in the IP cameras have improved over the years, resulting in advanced noise reduction technology that enhances low-light performance. The advanced computer inside the special cameras also provides image correction, which maintains brightness, color reproduction, and sharpness in extremely low-light environments.
Better lenses have become available that have higher light transmission. The f-stop of a lens represents the aperture (opening) that allows light to reach the sensor. The lower the F-number of a lens, the more light is transmitted. The lenses available have changed from F-2.0 to F-0.94
Lux is the unit of measure that describes the amount of light falling on a surface. We use this to describe the low-light sensitivity of a camera. The lower the number, the better the low-light sensitivity of the IP camera. Low-light capability in IP cameras has improved from 1 lux to 0.0004Lux (in BW with an F0.94 lens).
Why is lowlight performance important? These new cameras can see in starlight. Improved performance has increased security at night.
Wide Dynamic Range Improved
Dynamic range describes how well a camera can see in a scene that has very bright and dark areas. For example, if the camera was viewing a sunlit window and a person walked in front of the window, it was hard to see the person’s details. The background, a large bright area, would wash out the foreground image.
The latest cameras have faster video processors that allow them to capture one frame in 1/120th of a second. For each frame they capture, they adjust the exposure of the shot and then average them. The resulting video has an increased wide dynamic range WDR). Many cameras, such as the Hanwa extremeWDR cameras, average the exposures over four 1/120s frames.
Why is Increased WDR Better
- During daytime, when it is relatively dark inside a building and sunny outside. The improved WDR allows you to see a person in the foreground and the bright background outside the window.
- In a situation where there is a bright light shining towards the camera, such as with a car approaching the camera with its headlights turned on, it is possible to see the license plate with increased WDR.
AI-Enhanced Camera Systems
AI-enhanced cameras have created a paradigm shift in the way surveillance cameras are used. This revolutionary computer capability combines real-time video monitoring with artificial intelligence to detect and respond to problems as they happen. These intelligent systems transform the way organizations protect their people, property, and operations by proactively addressing dangers instead of reacting to them later.
Why are AI-Enhanced Camera Systems Beneficial
- Gun detection: AI-enhanced cameras can watch the entry points of a facility and alert security if someone enters with a gun. This technology is making schools, hospitals, and government facilities safer.
- Real-Time Alerts: AI can detect behaviors like unauthorized access, aggressive actions, or crowd congestion and send instant alerts to security personnel.
- Notify security if someone falls: AI-enhanced cameras can detect if someone falls and doesn’t get up in a certain amount of time
Summary of Advances in Surveillance Camera Systems
Surveillance cameras have evolved from analog camera systems that had to be watched all the time, to video-recorded systems, to sophisticated intelligent systems that detect problems when they occur. The IP camera took the surveillance market to a new level of capability, providing increased resolution, better low-light capability, and better dynamic range. The advent of AI-enhanced systems made the surveillance systems much more effective and capable of detecting real-time problems.
If you need help determining the best way to increase your organization’s security. Please get in touch with us at 914-944-3425, email [email protected], or use our contact form.