Computer vision is an AI technology that deals with the visual interpretation of images and videos of your desktop. It works automatically to produce the virtual information in numeric form. It does so through the extraction of digital data. But to run a computer vision on your system, you need a camera. Now the question is, how do I choose a camera for computer vision?
When it comes to computer vision cameras you have to know a few things. This guideline will feature all the essential steps you need to check before selecting a camera for your computer vision.
Different Cameras and Their Purpose in Computer Vision
The type of camera also holds a prominent position in the selection of vision cameras. In markets, there are different types of cameras available. And every camera impacts differently on your computer vision.
Webcam
The webcams are being used for a wide variety of applications and nowadays it has become more popular whether it is content creation and online classes. You can use it for any other personal use. You can find many webcams for computer vision.
Area scan camera
A monochrome or PoE area-scan camera increases the imaging process automatically. That’s why industries use area-scan cameras to enhance their production.
Line-scan camera
A high-speed camera link assists your computer vision in destructive testing and inspection purpose. Thus, a camera link is usually used by the aerospace and transportation department. In contrast, a GigE line-scan camera delivers the best image resolution. As digitization takes place within this camera, they produced accurate images with a wide range of resolutions.
Monochrome and Color camera
Currently, monochrome cameras and color cameras are widely in use. Suppose the difference between them is based on sensing points and hue. Then, color cameras have a clear edge over the monochrome camera.
But if you need a camera with a proper measurement dimension, you prefer backlight in your images. Then, you need to choose a monochrome camera. These types of cameras will provide you a higher contrast change.
Moreover, for dimensional measurements, the color cameras are not as appropriate as monochrome. As they optimize the Bayer filter to enable the full-color resolution.
Each camera serves its purpose for computer vision. Select one that suits your everyday usage.
Area-scan Camera vs Line-scan Camera
In my opinion, selecting a camera that fulfills your system requirement is the key to success here. Currently, area-scan cameras and line-scan cameras are among the best vision camera available. But how do you choose one of them?
When to choose an Area-scan camera?
Area-scan cameras come with a built-in sensor of 640 x 480 pixels or 1280 x 960 pixels (width and height). They are mainly used when you have to capture the whole image in one click. Area-scan is also recommended when
- Image or video displays on a computer screen directly.
- Moving subjects within the videos require a bright strobe to resist motion.
- A movie or a shot is in the range of area-scan camera sensor resolution.
- The picture frame only needs a single shot to capture.
- Users want a simple device to handle.
When to choose a Line-scan camera?
The line-scan camera has a sensor of a much higher resolution of 2000 x 1 or 8000 x 1 pixels. They support images of the long and narrow medium. If you capture the moving scene from the narrow axis with the output setting of one line per frame. Then it will provide you a two-dimensional image with a line-scan camera.
Line-scan cameras are the best choice when:
- Users want a resolution higher than that of an area scan camera.
- The filmed object is in a continuous motion with the sensor.
- The timing of the moving scene needs to be preset within the camera.
Both area-scan and line-scan cameras will provide you better quality with desired results. But many users who are in search of the vision camera best for everyday usage select area-scan camera.
What’s Your Resolution Requirement?
After choosing your preferred camera type, the next step is to find your resolution requirement. The resolution of the camera holds a significant place in your selection. As the quality of the extracted image relies on it. If you want to detect or measure a component of interest within your image. Then a camera with a minimum of two-megapixel resolution will do your work.
However, the featured component must not excel over half of the pixel size of the camera. In particular, a VGA camera usually comes with a built-in resolution of 640 x 480 pixels. It measures the lowest component with 1/320 pixels horizontally and 1/240 pixels vertically.
Advantages of High-Resolution Sensor
In my perspective, by using a high-resolution sensor, you will be able to get a better insight. As it will provide you the minor component within the available field of view (FOV). Some high-resolution sensors tend to increase the FOV too. If you’re using a sensor with low pixels, you need to handle them with care.
The resolution power of optics within the system must coincide with the low pixels sensor. In fact, the advantage of using high-resolution tappers down if they will be used with the optics of low magnification. However, the high magnification optics tends to show a minimum pixel size effective for your required resolution.
What’s Your Preferred Communication Interface?
In this step, you will get to know what are the types of communication interfaces. And how to choose one to enhance your computer vision with a webcam. Some of the most reviewed communication interfaces are mentioned below with their respective camera manufacturers, pros, and cons.
USB 2.0
USB 2.0 is the most economical option available. All you need to do is to connect your camera with a cable that comes with an extension of 5 meters. Isn’t that simple? But this interface cannot support any activity above 480 Mbps. That’s why it is not recommended to you if your use data transmission daily.
USB 3.0
The upgraded version of USB 2.0. USB 3.0 follows a similar interface and installation to USB 2.0. But it supports the activity of higher output with a stable, reliable, and longer data transmission. That’s why USB 3.0 holds the title of best USB camera for computer vision.
Camera Link
The camera link supports massive throughput and it will give you an output of up to 6 Gbit/s. Therefore, it’s the perfect choice for high-resolution images. It is one of the expensive communication interfaces. But it will also provide you with the most extended cable extension of 10 meters. That’s why camera link advantages overtake its price range in the longer run.
PoE
PoE or Power Over Ethernet is a type of communication interface that supports the activity of 1 Gbit/s. But its chief advantage is to provide a power supply to the camera during data transmission.
These modes of communication interfaces are among the best suggestions. However, selecting one of them will demand your work preferences and system.
Frequently Asked Questions
What can you do with computer vision?
Traffic sign detection and recognition are the key benefits of computer vision. Vision techniques of image segmentation have been used to separate traffic signs from various traffic features. Computer vision also works in the programming of learning algorithms. As it enables your system to interpret traffic signs.
Why is computer vision so important?
Computer vision assists self-driving cars to their surroundings. They also play a massive part in the facial recognition application to provide security in various firms. The latter technology permits the computer to match the individual face image with their given identity.
Is machine vision the same as computer vision?
The matter of scope is the root cause of differentiation among them. Computer vision application runs on PC processors that does data analysis deeply. Thus, computer vision can process more visual information than machine vision.
How to select a lens?
The lens and its pixel size play a key role in selecting the best camera for computer vision. The FOV is also dependent upon the sensor size and its optics. For computer vision, the highly reviewed sensor sizes include 1/2 and 1/3 types. Before selecting a lens, measure your lens pixel size. It must be equal to or more than your camera’s sensor size, Otherwise, it is of no use.
How to measure the pixel size of a lens?
Pixel size or the pitch of the lens is usually measured in microns. However, to calculate a pixel size, all you need to do is determine the distance between two adjacent pixel centers. If you want to know the sensor’s active imaging size, you have to multiply its pixel size with active pixels.
The Bottom Line
We have discussed all the key points in this guideline. How do I choose a camera for computer vision? Now this question is making sense to you. In the end, before selecting a vision camera, set your priorities suitable. Knowing your workload demands, budget, and resolution requirements will help you to make the right decision.