Video Security Systems – Megapixel and HD

The video security industry has come a long way in recent years. We have graduated from tube cameras and VCRs to network cameras and digital recorders. This technology upgrade has given us higher performance capabilities and improved image quality.

 

One of the advantages gained in recent years is megapixel image capability. Images are made up of dots called pixels (picture elements). The more pixels an image has, the higher the image resolution and quality. Analog video has a typical maximum resolution of 640 x 480 pixels, commonly called VGA resolution. VGA resolution gives images with 307,200 pixels.

 

Megapixel means one million pixels. Megapixel images have one million or more pixels. A baseline megapixel image has four times the number of pixels as an analog image. With multiple megapixel images, the difference becomes even more significant.

 

The difference between VGA and megapixel resolution becomes apparent when recorded images are enlarged. Due to the higher number of pixels in a megapixel image, the image itself can be enlarged by more factors than a VGA image and still produce a usable image. The higher the megapixel of the image, the further the image can be enlarged and still produce usable results.

 

The unfortunate aspect of megapixel cameras is the lack of industry standards. There are no universally adopted industry standards for camera performance, so two cameras with identification megapixels can produce different image results under the exact same conditions. A careful reading of the specification sheet for the camera and understanding of how measurements were taken is required to do a fair comparison.

 

The introduction of HD (high definition) video products provided a performance standard to the video security industry. HD provides megapixel performance to a set of standards set forth by the SMPTE (Society of Motion Picture and Television Engineers). The HD video standards of the SMPTE call for performance standards that include 16:9 aspect ratio (widescreen), 30 images per second of video, and color quality and performance standards.

 

HD video performance is expressed in lines of vertical resolution and the scan method (with P – progressive being more common) or by an identifying title. The most common standards currently used:

Standard

Title

Megapixels

720P

Standard HD

0.9 MP

1080P

Full HD

2 MP

2160P

4K

8 MP

4320P

8K

33 MP

 

Comparing HD to Megapixel

Standard

HD

Megapixel

Aspect Ratio

16:9

4:3

Vertical Pixels (lines)

720, 1080, 2160, or 4320

Various

Megapixels

0.9, 2, 8, 33

1.2 to 8

Images per Second

Variable

30

Performance Standards

Yes

No

 

Want to learn more about video security systems? Check out our online, self-paced training (Training Department): Security section, or the NTC Yellow Book: Video Security System Handbook.

Upcoming VIrtual Classes

Nov 10

NICET Fire Alarm 1&2 Virtual Classroom: Pacific Time

November 10 @ 8:00 am - November 11 @ 5:00 pm PST
Nov 17

NICET Fire Alarm 3&4 Virtual Classroom: Pacific Time

November 17 @ 8:00 am - November 18 @ 5:00 pm PST
Nov 19

Low Voltage Competency Virtual Classroom: Pacific Time

November 19 @ 8:00 am - November 20 @ 5:00 pm EST
Dec 01

NICET Fire Alarm 1&2 Virtual Classroom: Eastern Time

December 1 @ 8:00 am - December 2 @ 5:00 pm EST
Dec 08

NICET Fire Alarm 1&2 Virtual Classroom: Pacific Time

December 8 @ 8:00 am - December 9 @ 5:00 pm PST

Upcoming Free Training Opportunities

Thu 29

Free Webinar: Is Your AHJ Right or Wrong?

October 29 @ 1:00 pm - 5:00 pm EDT
Nov 19

NFPA 72 – Notification

November 19 @ 1:00 pm - 5:00 pm EST
Dec 10
Dec 17

10 Things Your IT&M Contract Should Have

December 17 @ 1:00 pm - 2:00 pm EST