Welcome to e-con Systems' Vision Vitals, your weekly podcast on embedded vision and camera selection.
This week, we talk about what happens when a camera makes an object look bigger, but the system still misses the detail.
So why does a zoomed image sometimes fail during inspection? And when a sensor gives you more pixels, does that always translate into better embedded vision output?
These questions come up often when comparing resolution and magnification.
To help unravel the logic behind these, we have our in-house vision expert with us today.
Good to have you here.
Thanks. It's great to be here!
Host:
Can we start with the simplest version? What is magnification in an embedded vision system?
Speaker:
Magnification is the process of increasing the apparent size of an object or an image.
In embedded vision, that can happen through optical lenses or digital zoom. Optical zoom adjusts the focal length of the camera lens. Digital zoom uses software to enlarge the image.
Host:
So when teams zoom in, are they always getting more usable detail?
Speaker:
Hmm, that depends on resolution. Magnification can make details easier to see, but it cannot create image detail that the sensor failed to capture.
If the imaging system has limited resolution, increasing magnification can simply enlarge blurred or indistinct details. The image becomes larger, but the system gains little useful information.
Host:
Is that what we refer to as empty magnification?
Speaker:
Yes. Empty magnification happens when an image is magnified beyond what the resolution can support. At that point, extra enlargement reveals very little added detail.
Host:
How does resolution change that equation?
Speaker:
Resolution refers to the level of detail, or the number of pixels captured by an image sensor or displayed on a screen. It is usually expressed using horizontal and vertical pixel counts, such as 1920 x 1080 or 4K, which is 3840 x 2160.
Higher resolution images contain more information. That can support better analysis and decision-making in embedded vision applications.
Host:
What else affects high-resolution imaging apart from pixel count?
Speaker:
Pixel size, sensor quality, and image processing algorithms influence the ability to capture high-resolution images. So one should look at resolution as part of the full camera system, including the sensor, lens, processing path, and application requirement.
Host:
If magnification makes details larger and resolution captures more detail, how should product developers think about the relationship between the two?
Speaker:
They are connected.
Magnification can increase the perceived resolution of an image by enlarging details so that they become easier to analyze. Higher resolution can improve the amount of detail captured or displayed, even when magnification is absent.
The best combination depends on the embedded vision application.
Host:
Can you make that practical?
Speaker:
Microscopy makes this easier to see. High resolution helps distinguish fine details. Magnification enlarges those details for analysis. The balance between the two determines whether the system can provide detailed images for accurate observation and measurement.
Host:
What about industrial inspection?
Speaker:
Industrial inspection and quality control may require magnification in the 5x to 20x range. But the magnification has to work with enough resolution. Otherwise, the system may enlarge defects or edges while still losing the detail needed for inspection.
Host:
Let's talk about medical imaging? How do things work there?
Speaker:
Medical imaging may require magnification of 100x to capture detailed images of biological samples and tissues. Resolution plays a major role there because the system has to capture fine structures before magnification can make them useful for analysis.
Host:
Where does embedded vision performance enter the picture?
Speaker:
Resolution impacts performance in two directions.
First, higher resolution gives the system more visual information. This can help applications such as microscopy, surveillance, object recognition, and human-machine interaction.
Second, higher resolution increases the amount of image data. That affects compute, power, storage, transmission, and cost.
Host:
Let us take those one by one. How does resolution affect compute?
Speaker:
Higher resolution images and magnification techniques usually require more computational power for processing and analysis.
Embedded systems often work with limited processing resources. Large image frames can create bottlenecks or delays, mainly when the system needs real-time analysis.
Host:
So if a product team wants a high-resolution sensor, what should they check on the processing side?
Speaker:
They should check whether the processor can handle the image size, frame rate, and analysis workload. The camera output has to match the embedded platform's ability to process the data.
Host:
How does power consumption change when resolution increases?
Speaker:
Higher resolution and magnification can increase power consumption. This becomes important for battery-powered embedded vision systems or any system where energy use has to be managed carefully.
Host:
What happens to storage and transmission when image resolution increases?
Speaker:
High-resolution images create larger file sizes. That can strain storage and transmission capacity, mainly in systems with limited bandwidth or storage.
Host:
Why does a frame buffer matter for embedded vision?
Speaker:
A buffer helps manage image data when full frames need to be stored and retrieved. This can help when the system handles larger frame sizes and needs a stable transfer.
Host:
How does resolution affect cost?
Speaker:
Higher resolution sensors, lenses, and processing hardware can increase cost. That can make some systems harder to build within a target price range.
Host:
If one is choosing sensor resolution, what questions should they ask before choosing the camera?
Speaker:
They should ask what detail the camera must capture, how large the object should appear in the image, how much magnification is required, how much processing capacity the platform has, and what storage or transmission limits exist.
They should also consider cost because a higher resolution can affect the sensor, lens, processor, and overall system.
Host:
Where do people usually go wrong with magnification?
Speaker:
A common issue is treating magnification as a substitute for resolution. If the image lacks enough pixel detail, zooming in only makes weak detail larger.
Host:
I'm assuming teams also can go wrong with resolution, right?
Speaker:
Oh yes! They may select a very high-resolution sensor before checking compute, power, storage, transmission, and cost. The image may contain more data, but the embedded system has to process and move that data at the required rate.
Host:
So what is the practical balance between resolution and magnification?
Speaker:
The camera should capture enough detail first. Then magnification should make the relevant detail easier to analyze. If the two are balanced, the embedded vision system can deliver better image quality and more accurate observation or measurement.
Host:
How does this apply to surveillance?
Speaker:
In surveillance, higher resolution can help capture more scene detail. Magnification can bring a region closer for review or analysis. But the system still has to handle the larger data load and maintain usable image output.
Host:
How does this apply to object recognition?
Speaker:
In object recognition, higher resolution can provide more information about object features. That can support better analysis. But real-time recognition also depends on the processing platform, data transfer, and overall camera setup.
Host:
How does this apply to human-machine interaction?
Speaker:
Human-machine interaction may depend on visual cues. Resolution can influence how much detail the system captures, while magnification can help make certain regions easier to analyze.
Host:
Nicely put! Really appreciate your insights.
Speaker:
It was my pleasure. Can't wait to do this again.
Host:
Likewise!
So, folks, thank you for spending time with us today. Hope this episode makes the next conversation about your application's imaging capabilities a little easier.
Please visit e-con Systems dot com to view our camera portfolio. You can also use our Camera Selector to compare options based on your specific needs.
And if your application has a challenging imaging requirement and you need to talk to an expert, drop a note to camerasolutions@e-consystems.com. Our vision experts will be happy to help you think it through.
We'll see you in the next episode.
Until then, stay sharp!
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