|Image Scan||Progressive Scan||Interlaced|
|Resolution||Multi-Megapixel||.4 Megapixel (4CIF)|
|Cabling||Single cable for audio, video, power and PTZ control||Multiple cables required|
|Analytics||Embedded in camera||Built into server|
|Integration||Open software applications like Axxon Enterprise work with multiple hardware and software applications||Usually proprietary operating systems with limited integration capability|
|Security||Encrypted video transmission||No encryption on transmission|
Both the PAL and NTSC video standards actually capture and transmit a video image as 2 separate fields in a process called interlaced scanning. The first field contains the even horizontal lines and the second field contains the odd horizontal lines. Upon reception, both fields are interwoven to render the complete image for viewing on the CCTV monitor. Blurring often occurs if objects in the video are moving quickly. When an object moves between the capture of the first and second field, it will be horizontally offset when the two fields are combined for viewing. The solution is to use Progressive scanning, available in only in network cameras. Progressive scan sensors scan and transmit a single, full image.
The NTSC and PAL video standards define the maximum resolution as 704×480 and 720×576 respectively. Digital video imposes no limitations. Megapixel resolutions of up to 2596×1944 (5 Mega pixels) are available in some network security cameras today.
Running IP over Cat5e/Cat6 Ethernet provides a single cable for the transmission of audio, video, pan tilt control and relay contacts. Power over Ethernet further reduces the cable infrastructure by eliminating separate power cables.
Video analytics from basic motion detection to advanced object tracking algorithms are moving to the “edge” of the network. Advances in computing power make it possible for manufacturers to embed analytics into network cameras and video encoders. This reduces the need and expense of centralized computing power to uncompress and analyze digital video. Based on the analytics, the edge device can make real-time decisions about video quality transmission.
Software-based security systems provide unlimited integration opportunities – even for standalone systems such as access control, intrusion and fire. What’s more, by integrating your security system into your business systems, such as point-of-sale terminals, you transform your system from an expense to an asset. New security systems are quickly migrating to standards-based IP interfaces to enable software integration.
Video transmission over IP networks offers several security advantages. First, the video is more difficult to “tap”. Analog signals transmitted over coax cable can be tapped with a monitor or DVR. Unlike analog CCTV signals, IP video can be encrypted. Furthermore, the connections to the camera can be authenticated using standard certificate mechanisms and each video frame can be “watermarked” with an identifying fingerprint to ensure its authenticity for forensic evidence.