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Webcam Pulse Detector

github.com

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Re: Webcam Pulse Detector

#52
post #49
post #47

Earlier quoted context omitted.

that's the tragedy of it. something cool is invented and now it'll be fenced off and buried for 25 years in all likelihood, and/or becomes part of a big patent portfolio.

doesn't a patent imply that you must let other people use your idea in exchange of a fair price?

ICBW, but no, I don't think it does, except it perhaps a narrow set of circumstances.

Compulsory Licensing[1] is maybe what you're thinking of, but from what I can tell seems to apply mostly to drug patents, or things {the,a} government wants from you. It has a wider applicability in copyrighted forms of IP, I believe.

Patents that are part of some organised standard are often required to be placed under 'FRAND[2] (Fair, reasonable, and non-discriminatory)' compulsory licences to allow for interoperability whilst still allowing the patent holder to receive (reasonable) royalties if they wish.

[1] https://en.wikipedia.org/wiki/Compulsory_licensing

[2] https://en.wikipedia.org/wiki/Reasonable_and_non-discriminat...

Re: Webcam Pulse Detector

#53
post #49
post #47

Earlier quoted context omitted.

that's the tragedy of it. something cool is invented and now it'll be fenced off and buried for 25 years in all likelihood, and/or becomes part of a big patent portfolio.

doesn't a patent imply that you must let other people use your idea in exchange of a fair price?

Nope.

Re: Webcam Pulse Detector

#54
post #49
post #47

Earlier quoted context omitted.

that's the tragedy of it. something cool is invented and now it'll be fenced off and buried for 25 years in all likelihood, and/or becomes part of a big patent portfolio.

doesn't a patent imply that you must let other people use your idea in exchange of a fair price?

No, a patent implies that you publicly disclose the knowledge behind your discovery immediately, in exchange for the property of this knowledge being guaranteed† to be yours for a limited time, and its use guaranteed to become free when this time runs out.

The alternative is not to disclose it, with the risk for you that nobody will reverse engineer or discover by themselves, or the risk for everyone else that this knowledge could be lost forever.

† pending approval, and unless successfully challenged in court (where the patent applies).

Re: Webcam Pulse Detector

#55
post #18

Has anyone been able to get it to work? Whenever I try to open the stats display, I get: OpenCV Error: Assertion failed (p.checkVector(2, CV_32S) >= 0) in polylines, file /tmp/buildd/opencv-2.3.1/modules/core/src/drawing.cpp, line 2064

works for me on OSX 10.7.5, with opencv @2.4.4_3+python27 installed via macports.

I did have to downgrade to the ffmpeg (ffmpeg @1.2_1+gpl2+nonfree) port (from ffmpeg-devel) due to build errors in opencv, but worked ok after that.

Couple of the openMDAO packages didn't install either, but didn't seem to harm anything.

Re: Webcam Pulse Detector

#56

How precise is this, do we have data? I'm guessing it depends on the refresh rate of your webcam.

when I have some time and can dig out my pulse oximeter, I'll see if I can hack it in for comparison. Based on trying to take my pulse manually it certainly seemed in the ballpark, and got even better/stronger locked results from using my thumb ~5-10cm from the camera.

It seems quite sensitive to image saturation for losing lock though.

Re: Webcam Pulse Detector

#57

Earlier quoted context omitted.

I expect to see this used by DJs, where the momentum of the music is controlled by the crowd.

Need way more light than that for a standard camera... now, maybe with an IR camera...

Perhaps stage lighting could be used to illuminate the crowd...green lighting perhaps? :)

Re: Webcam Pulse Detector

#58
post #29
post #27

Earlier quoted context omitted.

And isn't this the case? 15 fps (worst case framerate) vs 3 bps (worst case heart rate)

I dont believe so. Since the heart rate could be much higher, it would alias, and the camera wouldn't be able to tell the difference between normal heart rate and low heart rate. This is what I suspect could happen, with two possible heart rates matching the same set of samples: http://upload.wikimedia.org/wikipedia/commons/2/28/AliasingS...

Since the heart rate could be much higher

Err - why do you say that? If your heart rate is much higher then either you aren't human or your are probably dying.

Did you read my original comment?

Human heart rates range roughly between 30 to 200 beats per minute. That maxes out at a bit over 3 beats per second.

Re: Webcam Pulse Detector

#60
This would be an awesome application for google glass! Does anyone know if it's possible?

Imagine being able to look at someone and know their pulse. You'd have a wearable lie detector.

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