Needless to say, different IP camera resolutions are available, from 720p to 4K and beyond. How then should the user decide what’s best for them? This article seeks to explore this topic.
Needless to say, different IP camera resolutions are available, from 720p to 4K and beyond. How then should the user decide what’s best for them? This article seeks to explore this topic.
Resolution is important in the camera selection process. It determines how well video can be captured and seen. Right now, the mainstream IP camera resolution is
2 megapixels (MP) or 1600 x 1200 pixels.
Yet increasingly, IP cameras are trending towards higher resolution, from 2MP to 5MP, 6MP,
8MP (or 4K) and even higher.
“We see, at least in sales in 2022, that the mainstream IP camera will change from 2MP to a higher resolution of 5MP and 8MP+. In terms of volume, the 2 MP solutions still dominate the market. However we do see a breakeven between 2 and 5MP designs expected in 2022,” said Hartmut Sprave, CTO of MOBOTIX. “The 8MP cameras – for example the MOBOTIX 7 series – may still be seen as a niche product, but we are convinced that the more demanding an application is to be, the higher the resolutions will be required.”
Advances in IP camera technologies and components, such as lens and image processors, have a big part to do with this.
“Lenses are often composed of many different lens elements that work together to achieve the desired focal length. A few years ago, there were only a handful of 4K lenses available. Now they are plentiful, even going beyond 4K to 8K,” said Aaron Saks, Senior Technical Marketing and Training Manager at Hanwha Techwin.
“With the increasing power of image processing chips, the processing time for larger sensors is no longer such an obstacle. Larger image sensors allow greater areas of interest and are no longer limited by image processing speeds for most applications. As a result, image sensors with higher resolutions are becoming more important and more prevalent,” said Jeff Gohman, Co-Founder, President and Chief Optical Designer at Theia.
Benefits
Indeed, high-resolution cameras attract with their many benefits. “High(er) resolution cameras allow you to capture footage in greater details and offer some level of enhanced zooming capabilities without as much loss of quality. A 4K 3840 x 2160 camera is effectively 4x the resolution of an HD camera. This means you can zoom into an image much more before it becomes pixelated. This can mean the difference between identifying someone or not,” said Tim Loth, Sales Engineer Team Lead at i-PRO Americas.
“A higher resolution camera will give you a better image with more detail and more information. It will allow users to digitally zoom in further and provide a superior experience,” said Kambiz Asrar Haghighi, Director of Product Management for Video Security and Access Control at Motorola Solutions, adding certain applications can especially benefit.
“High-resolution cameras are ideal for large areas that require coverage such as airports, stadiums, campuses. They are also beneficial when users need to zoom in on small details such as the text on a receipt in a retail setting,” he said.
Challenges
There are also certain challenges associated with high-resolution cameras. As these cameras have to pack more pixels into their sensor, if the sensor doesn’t significantly increase in size, the low-light performance of the camera will suffer.
“Since security cameras are used 24x7 and in difficult and changing lighting conditions, often with integrated IR, low-light performance is very important. You don’t want half of your video to be noisy or of poor quality simply to get more pixels for the other half of the day. Bad-quality video becomes worthless,” Saks said. “It is better to lower the resolution and increase the performance; or choose a manufacturer that can provide high-resolution, high-quality imaging day and night.”
Also, inevitably, high resolution leads to higher bandwidth and storage usage, which can be costly. This is where users can rely on smart compression technologies, which can help reduce bitrate yet maintain video quality.
“Any compression algorithm is subject to data loss. At the same time, it makes sense to save bandwidth and reduce the network load. Today’s efficient camera video-encoder such as H.254/H.265 support this requirement. On top adding intelligent encoding software, an enormous quality level can be achieved here,” Sprave said.
“Smart Coding technology is a feature on all i-PRO cameras. It is based on the idea of assigning less compression to important parts of the image such as people, faces, cars and objects in motion, while compressing the static background of an image more. This reduces the total bitrate throughput (and data storage) substantially while ensuring image quality where it counts. Similar to how audio compression (MP3) operating on sounds we do not hear, video compression acts on areas of the image that the eye considers irrelevant to the scene,” Loth said.
How to decide what resolution works for you
Given different camera resolutions available now, how should the user decide what works for them? This requires the user to get a full understanding of their needs and requirements – for example how wide is the area of coverage and how detailed the video data must be.
“The main thing to consider is the area that needs to be covered. High resolution cameras are getting more and more common/popular because they give you a crisp image and a greater level of detail, but they may not cover everything depending on their field of view. Depending on the deployment, they can provide excellent coverage with less physical cameras required. For example, a bank might be able to halve the number of cameras required to cover the tellers if it went from HD to 4K sensors. Choosing the right camera (resolution) means first understanding what the use case is and what area the user wants to cover,” Loth said.
“It all comes down to pixels on target. The integrator needs to work with the customer to understand the security goals of each camera to then determine the needed pixel density and matching lens. Often you can increase a camera’s resolution while choosing a wider-angle lens to cover a larger area with fewer cameras. However, this doesn’t provide an increase in forensic detail. If the customer requires higher forensic detail to be able to zoom in further, they can then increase the resolution,” Saks said.
Meanwhile, selecting the right resolution can be based on four criteria – detection, observation, recognition and identification. There are
calculators that help use make the selection based on those criteria. “Ultimately, it should be based on the application and the pixels per foot required on the area of interest for detection, observation, recognition, and identification (DORI). Based on how far the region of interest is from the camera, the right lens and resolution can be selected to reach the DORI goals. Tools like the MSI System Design Tool (SDT) aid in selecting appropriate cameras, lenses, and resolutions to design an effective security system,” Haghighi said.