The Chinese Version: How to Recognize People From Quite a Long Way Away

Remember in January when OpenAI announced some great achievement, and then a few days later we learned that the Chinese firm DeepSeek could boast the same performance, only much better?

These Chinese leapfrogs don’t only happen in artificial intelligence.

One kilometer facial capture

In February, I wrote about something that I initially heard of via Biometric Update. My post, “How to Recognize People From Quite a Long Way Away,” told of an effort at Heriot-Watt University in Edinburgh, Scotland in which the researchers used light detection and ranging (LiDAR) to capture and evaluate faces from as far as a kilometer away.

In normal circumstances, we capture faces from a distance of mere meters. So one kilometer facial capture is impressive.

Or is it?

One hundred kilometer facial capture

Some Chinese researchers replied, “Hold my Tsingtao,” according to a Chinese Journal of Lasers paper (in Chinese) that was reported on by Live Science (in English). (And again, I learned of this via Biometric Update.)

Scientists in China have created a satellite with laser-imaging technology powerful enough to capture human facial details from more than 60 miles (100 kilometers) away….

According to the South China Morning Post, the scientists conducted a test across Qinghai Lake in the northwest of the country with a new system based on synthetic aperture lidar (SAL), a type of laser radar capable of constructing two-dimensional or three-dimensional images.

Qinghai Lake, from Google Maps.

Writers will note that the acronym SAL incorporates the L from the acronym LiDAR. This is APO, or acronym piling on.

Since I cannot read the original report, I don’t know if the researchers actually performed tests with actual faces. But supposedly SAL “detected details as small as 0.07 inches (1.7 millimeters),” based in part upon the benefits of its technology:

[T]his new system operates at optical wavelengths, which have much shorter wavelengths than microwaves and produce clearer images (though microwaves are better for penetrating into materials, because their longer wavelengths aren’t scattered or absorbed as easily).

All the cited articles make a big deal about the 100 kilometer distance’s equivalence to the boundaries of space. But before you get too excited, remember that a space-hosted SAL will be ABOVE any human subjects, and therefore will NOT capture the face at an optimal angle…

Can you identify Bart Everson’s face from this picture? For all I know it could be Moby. CC-BY-2.0, https://www.flickr.com/photos/editor/158206278.

…unless you’re lying on the beach sunbathing and therefore facing TOWARD space where all the Chinese satellites can see you.

Oh, and one more thing. The Chinese tests were conducted in optimal weather conditions, and obviously you can’t get the same results in bad weather.

But in the ideal conditions, perhaps you CAN be identified remotely.

(Snowman from Imagen 3)

How to Recognize People From Quite a Long Way Away

I can’t find it, and I failed to blog about it (because reasons), but several years ago there was a U.S. effort to recognize people from quite a long way away.

Recognize, not recognise.

From https://www.youtube.com/watch?v=ug8nHaelWtc.

The U.S. effort was not a juvenile undertaking, but from what I recall was seeking solutions to wartime use cases, in which the enemy (or a friend) might be quite a long way away.

I was reminded of this U.S. long-distance biometric effort when Biometric Update reported on efforts by Heriot-Watt University in Edinburgh, Scotland and other entities to use light detection and ranging (LiDAR) to capture and evaluate faces from as far as a kilometer away.

At 325 metres – the length of around three soccer pitches – researchers were able to 3D image the face of one of their co-authors in millimetre-scale detail.

The same system could be used to accurately detect faces and human activity at distances of up to one kilometre – equivalent to the length of 10 soccer pitches – the researchers say.

(I’m surprised they said “soccer.” Maybe it’s a Scots vs. English thing.)

More important than the distance is the fact that since they didn’t depend upon visible light, they could capture faces shrouded by the environment.

“The results of our research show the enormous potential of such a system to construct detailed high-resolution 3D images of scenes from long distances in daylight or darkness conditions.

“For example, if someone is standing behind camouflage netting, this system has the potential to determine whether they are on their mobile phone, holding something, or just standing there idle. So there are a number of potential applications from a security and defence perspective.”

So much for camouflage.

But this is still in the research stage. Among other things, the tested “superconducting nanowire single-photon detector (SNSPD)” only works at 1 degree Kelvin.

That’s cold.