If you’ve ever shopped for a security camera, you might have seen cameras being advertised as HD or high-definition. The term HD might be confusing to some people because they’re not exactly sure what makes a camera high-definition. Does HD refer to a specific type of camera or just any camera with a good resolution? If you’ve been asking the same questions, then keep reading.
MP vs. HD Security Cameras
Every camera’s image resolution can be determined by how many pixels make up each image. Higher resolution cameras will have more pixels which means that their images will look more clear and crisp. Lower resolution cameras will have less pixels and produce images that look blurry. Resolution can be measured in megapixels (MP) or the number of pixels (p) height-wise. To calculate the total pixel amount, you would multiply the width by the height. For example, a 2MP camera will have a width of 1920p and a height of 1080p. If you multiply the two figures together, you would get a total of 2,073,600p. This figure is roughly 2 million pixels or 2 megapixels so this camera can be said to have a resolution of 2MP or 1080p because that is how many pixels there are in the height.
Now that we know what MP means, how does HD fit into this? As mentioned earlier, every picture is made up of pixels. MP cameras refer to cameras that have at least 1 million pixels or 1MP. As of right now, the highest MP that exists is 10MP. HD security cameras are a subset of MP. HD only refers to security cameras that have a resolution of 720p (1MP) or 1080p (2MP). There are some manufacturers that will label any high resolution camera as HD, but this term will usually be reserved for only those 2 resolutions. Not every MP camera is HD but all HD security cameras are MP because they all meet the criteria of having at least 1MP.
HD Analog Systems
One important thing to note is that the term HD will usually be associated with analog systems instead of IP. In the past, the resolution of analog cameras were measured by the number of horizontal lines on the image, called TVL. When IP cameras were developed, their main advantage was that they were able to record in MP which meant higher resolutions and clearer images. But as technology advanced, manufacturers were able to produce new HD cameras, which were analog cameras that recorded in either 720p (1MP) or 1080p (2MP).
Thanks to the development of HD, analog cameras are now on par with some IP cameras when it comes to image resolution. This means that people no longer have to choose between using a simple analog system with low resolution or a complicated, high resolution IP system. HD is the best of two worlds; it combines high resolution with the simplicity of analog systems.