First-photon imaging

The compressive sensing blog Nuit-Blanche reports this publication: First-photon imaging. The technique allows to capture depth and (limited) reflectivity information using only a small number of photons (virtually in the dark).


Imagers that use their own illumination can capture 3D structure and reflectivity information. With photon-counting detectors, images can be acquired at extremely low photon fluxes. To suppress the Poisson noise inherent in low-flux operation, such imagers typically require hundreds of detected photons per pixel for accurate range and reflectivity determination. We introduce a low-flux imaging technique, called first-photon imaging, which is a computational imager that exploits spatial correlations found in real-world scenes and the physics of low-flux measurements. Our technique recovers 3D structure and reflectivity from the first detected photon at each pixel. We demonstrate simultaneous acquisition of sub-pulse duration range and 4-bit reflectivity information in the presence of high background noise. First-photon imaging may be of considerable value to both microscopy and remote sensing.

Making the subtle obvious, follow-up

A couple of months ago I was posting here about this SIGGRAPH publication on amplification of details in a video. Yesterday the New York Times put online a story as well as a video on the topic, with explanations from the authors and some new examples.

The science gap

I mentioned before the video by cartoonist Jorge Cham, illustrating the explanations of a CERN researcher on the Large Hadron Collider and the Higgs boson. This video was great and explained in layman’s terms the matter (pun intended) of this huge research project.

Today I watched a TEDx talk by Jorge Cham, tackling with what he refers to as the science gap, between the people who do science, and the general public. A part of his talk explains the story behind the Higgs Boson animation, and this story alone makes the talk worth watching.

Tour of the International Space Station

From the video description: “In her final days as Commander of the International Space Station, Sunita Williams of NASA recorded an extensive tour of the orbital laboratory […]. The tour includes scenes of each of the station’s modules and research facilities with a running narrative by Williams of the work that has taken place and which is ongoing aboard the orbital outpost.”

Making the subtle obvious

Take a video, decompose it into several frequency components, filter and amplify each one, recompose them back to an output video, profit. Nuit-Blanche mentioned this paper presented earlier this year at SIGGRAPH. I never thought you could actually detect the blood flow from a simple video…

Update: more to see in this follow-up post.

TED talk about femto photography

I already mentioned the camera built by a team in the MIT Media Lab, allowing with its trillions of frame per second, to capture the propagation of light or to see around corners.

TED published a video of the talk given by Ramesh Raskar, where he presents this work and the new possibilities it opens.