Review: InfiRay P2 Pro Thermal Camera

June 19, 2023 by 65 Comments

It probably won’t surprise you to learn that Hackaday is constantly hounded by companies that want us to review their latest and greatest gadget. After all, getting us to post about their product is cheaper, easier, and arguably more effective than trying to come up with their own ad campaign. But if you’ve been with us for awhile, you’ll also know that in-house reviews aren’t something we actually do very often.

The reason is simple: we’re only interested in devices or products that offer something useful or unique to this community. As such, the vast majority of these offers get ignored. I’ll give you an example. For whatever reason, multiple companies have been trying desperately to send me electric bikes with five-figure price tags this year. But since there’s no obvious way to turn that into useful content for the readers of Hackaday, I’m still stuck pedaling myself around like it’s the 1900s. I kid of course…I haven’t dared to get on a bike in a decade.

So I don’t mind telling you that, when InfiRay contacted me about reviewing their P2 Pro thermal camera, the email very nearly went into the trash. We’ve seen these kind of phone-based thermal cameras before, and it seemed to be more of the same. But after taking a close look at the specs, accessories, and claims laid out in the marketing material, I thought this one might be worth checking out first-hand.

Continue reading “Review: InfiRay P2 Pro Thermal Camera” →

Thermal Camera Reviewed

June 16, 2023 by 13 Comments

We keep thinking about buying a better thermal camera, as there are plenty of advantages. While [VoltLog’s] review of the Topdon TC002 was interesting though, it has a connector for an iPhone. Even if you aren’t on Android, there is a rumor that Apple may (or may be forced to) change connectors which will make it more difficult to connect. Of course, there will be adapters, and you can get a USB C version of the same camera.

Technically, the camera is pretty typical of other recent cameras in this price range, and they probably all use the same image sensor. The camera provides 256×192 images.

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Thermal Camera Plus Machine Learning Reads Passwords Off Keyboard Keys

May 4, 2023 by 43 Comments

An age-old vulnerability of physical keypads is visibly worn keys. For example, a number pad with digits clearly worn from repeated use provides an attacker with a clear starting point. The same concept can be applied to keyboards by using a thermal camera with the help of machine learning, but it also turns out that some types of keys and typing styles are harder to read than others.

Researchers at the University of Glasgow show how machine learning can pull details from thermal images like these quickly and effectively.

Touching a key with a fingertip imparts a slight amount of body heat, and that small amount of heat can be spotted by a thermal sensor. We’ve seen this basic approach used since at least 2005, and two things have changed since then: thermal cameras gotten much more common, and researchers discovered that by combining thermal readings with machine learning, it’s possible to eke out slight details too difficult or subtle to spot by human eye and judgement alone.

Here’s a link to the research and findings from the University of Glasgow, which shows how even a 16 symbol password can be attacked with an average accuracy of 55%. Shorter passwords are much easier to decipher, with the system attacking 6 and 8 symbol passwords with an accuracy between 92% and 80%, respectively. In the study, thermal readings were taken up to a full minute after the password was entered, but sooner readings result in higher accuracy.

A few things make things harder for the system. Fast typists spend less time touching keys, and therefore transfer less heat when they do, making things a little more challenging. Interestingly, the material of the keycaps plays a large role. ABS keycaps retain heat far more effectively than PBT (a material we often see in custom keyboard builds like this one.) It also turns out that the tiny amount of heat from LEDs in backlit keyboards runs effective interference when it comes to thermal readings.

Amusingly this kind of highly modern attack would be entirely useless against a scramblepad. Scramblepads are vintage devices that mix up which numbers go with which buttons each time the pad is used. Thermal imaging and machine learning would be able to tell which buttons were pressed and in what order, but that still wouldn’t help! A reminder that when it comes to security, tech does matter but fundamentals can matter more.

Calibrating Thermal Cameras With Hot Patterned Objects

March 18, 2023 by 7 Comments

Thermal cameras are great if you want to get an idea of what’s hot and what’s not. If you want to use a thermal camera for certain machine vision tasks, though, you generally need to do a geometric calibration to understand what the camera is seeing and correct for lens distortion. [Henry Zhang] has shared various methods of doing just that.

It’s all about generating a geometrically-regular thermal pattern.

To calibrate a thermal camera, first you need a thermal pattern. This is like typical test image for a camera or screen, but with temperatures instead of colors. [Henry] explains several methods for doing this. One involves using a grid of nichrome wires to create a thermal pattern for calibration purposes. Another uses discs of cold aluminium inserted into a foam board. Even a simple checkerboard can work, with the black spaces heating up more from ambient sunlight than their neighbouring white spots. [Henry] then explains the mathematical techniques used for calibrating based on these patterns.

It’s a useful primer on the topic if you’re working with thermal camera systems. We’ve looked at some other interesting machine vision topics before, too. If you’ve got any great thermal imaging tips of your own, don’t hesitate to drop us a line!

 

Your Own Santa? Thermal Camera Roundup

December 22, 2022 by 51 Comments

With Christmas and other end-of-year celebrations, there are gifts. The problem is that your loved ones don’t really know what to get you. Who can blame them? Do you want an Arduino, a Raspberry Pi, or a Blue Pill? Is that 3D printer on sale better than the one you have? Do you even want a second printer? They don’t know. In the best case, they’ll give you gift cards. But sometimes you just have to buy yourself something nice. [Wired] has a suggestion: a phone-based thermal camera. Which one? They have four suggestions ranging from about $150 to $200.

Different people have different reasons for wanting a thermal camera. You can see hot spots in electronics, for example. Or pick out hot water pipes behind walls. The resolution is limited. The highest in the [Wired] review is only 206×136. For the digital camera buffs, that’s 0.028 megapixels! Some cameras have even less resolution. For example, one of the cameras has an 80×60 resolution but uses an optical camera to give the illusion of a higher resolution.

Continue reading “Your Own Santa? Thermal Camera Roundup” →

A working, partially disassembled thermal camera

Cheap Display Fix Brings Thermal Camera Back To Life

November 20, 2022 by 5 Comments

When it comes to repairability of electronic devices, much depends on how helpful the original manufacturer is. Some make repairs very easy by publishing detailed service manuals and selling spare parts. Others keep everything under wraps to protect their intellectual property, turning even a supposedly simple fix into a reverse engineering ordeal. When [BuyItFixIt] got his hands on a FLIR multimeter-thermal camera combination instrument with a broken display, he quickly found that FLIR was firmly in the “all our designs are top secret” camp and wouldn’t even tell him what kind of display they had used.

Not to be deterred, [BuyItFixIt] took the meter apart and tried to find out what was going wrong. The signals from the microprocessor seemed to reach the display OK, so the fault was somewhere in the screen itself. The display’s part number didn’t return any useful results online, but AliExpress did have a very similar-looking display available with a slightly different part number. This display seemed to work at first, but the instrument then got caught in a boot loop.

Unlike FLIR, the supplier of the replacement display was happy to supply datasheets, and even had one available for the original FLIR part. With this new information [BuyItFixIt] was able to deduce that the new screen didn’t output one signal that the processor expected to see, causing it to reset itself. A simple workaround was to connect the corresponding pin to a PWM signal from the backlight controller, which fooled the CPU into thinking the proper display was connected.

In this case, a $12 display and a single piece of wire were enough to bring an expensive instrument back to life, but things are not always that simple. More complex machines can take weeks to debug, even if parts are available. If not, you might even need to design your own. Continue reading “Cheap Display Fix Brings Thermal Camera Back To Life” →

Review: Mini AMG8833 Thermal Camera

August 12, 2021 by 29 Comments

In our ceaseless quest to bring you the best from the cheaper end of the global electronics markets, there are sometimes gadgets that we keep an eye on for a while because when they appear they’re just a little bit too pricey to consider cheap.

Today’s subject is just such a device, it’s a minimalist infra-red camera using the 8 pixel by 8 pixel Panasonic AMG8833 thermal sensor. This part has been around for a while, but even though any camera using it has orders of magnitude less performance than more accomplished models it has remained a little too expensive for a casual purchase. Indeed, these mini cameras were somewhere above £50 ($70) when they first came to our attention, but have now dropped to the point at which they can be found for somewhere over £30 ($42). Thirty quid is cheap enough for a punt on a thermal camera, so off went the order to China and the expected grey parcel duly arrived.

The interface on this camera is about as simple as it gets.
The interface on this camera is about as simple as it gets.

It’s a little unit, 40 mm x 35 mm x 18 mm, constructed of two laser-cut pieces of black plastic held together by brass stand-offs that hold a PCB between them, and on the front is a cut-out for the sensor while on the rear is one for the 35mm OLED display.At the side on the PCB is a micro USB socket which serves only as a power supply. It’s fair to say that this is a tiny unit.

Applying power from a USB battery bank, the screen comes up with a square colour thermal picture and a colour to temperature calibration stripe to its left. The colours adapt to the range of temperatures visible to the sensor, and there is a crosshair in the centre of the picture for which the temperature in Celsius is displayed below the picture. It’s a very straightforward and intuitive interface that requires no instruction, which is handy because the device has none. Continue reading “Review: Mini AMG8833 Thermal Camera” →