What is the difference between HDTV, megapixel or standard resolution cameras?
High-definition television (HDTV) provides up to five times higher resolution than standard analog TV. HDTV also has better color fidelity and a 16:9 format. Defined by SMPTE (Society of Motion Picture and Television Engineers), the two most important HDTV standards are SMPTE 296M and SMPTE 274M.
SMPTE 296M (HDTV 720P) defines a resolution of 1280x720 pixels with
high color fidelity in a 16:9 format using progressive scanning at 25/30 Hertz (Hz)—which corresponds to 25 or 30 frames per second, depending on the country—and 50/60 Hz (50/60 fps).
SMPTE 274M (HDTV 1080) defines a resolution of 1920x1080 pixels with
high color fidelity in a 16:9 format using either interlaced or progressive scanning at 25/30 Hz and 50/60Hz.
Megapixel network cameras do not adhere to any standards, but is rather an adaptation of the industry’s best practices and refers specifically to the number of image sensor elements of the digital camera. For example, multi-megapixel network cameras often offer a limited frame rate.
In addition, some megapixel cameras offer “multi-view streaming”, which means that the same camera can deliver different video streams from different areas of a scene, which essentially leads to one megapixel camera replacing several standard cameras – for example, by monitoring more than one cashier in a retail store. Digital pan/tilt/zoom is another advantage offered by megapixel cameras.
Standard resolution. Even with the advantages provided by megapixel and HDTV cameras, there are many application areas where standard resolution network cameras provide the best solution. Standard resolution typically means VGA (640 x 480 pixels) resolution, which in many applications is more than enough to meet the video surveillance goals. Recently, SVGA network cameras have appeared on the market which provide higher resolution (800 x 600 pixels), while still not delivering megapixel images.
Conclusion. There is no single type of camera that is appropriate for all applications. Only by carefully analyzing the goals of your video surveillance installation can the right requirements be defined. Often the answer lies in combining HDTV network cameras and megapixel network cameras with a selection of standard resolution network cameras that are optimized for other needs. By balancing different types of network cameras, an IP-Surveillance solution can be designed that is effective, reliable and cost-efficient and fulfills the desired image usability