
Innovative Android/iPhone app uses camera and flash to check your heart rate - borismus
http://androidandme.com/2010/08/applications/check-your-pulse-with-instant-heart-rate/
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corbet
Looks like an interesting application, BUT: it wants full network access. Why
does this application need network access? We really need to start asking
questions like that...

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dagw
_Why does this application need network access?_

By the looks of it, to serve up ads and to send back usage statistics.

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wr1472
Yup upon install it says explicitly it uses Flurry analytics to monitor usage.

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araneae
Cool! I remember building one of these in school, except we used Matlab and an
infrared emitting led and an infrared detector.

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room606
I've not used this app but this is definitely possible and has been covered in
the literature. The final link is to a paper presented recently which actually
proposes using a mobile phone for this.

Would be interesting to see what other information can be extracted from
optical signals. Tricorders can't be that far off now.

[http://www.opticsinfobase.org/abstract.cfm?uri=oe-18-10-1076...](http://www.opticsinfobase.org/abstract.cfm?uri=oe-18-10-10762)

<http://vassilios-chouliaras.com/pubs/c51.pdf>

<http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2717852/>

[https://embs.papercept.net/conferences/scripts/abstract.pl?C...](https://embs.papercept.net/conferences/scripts/abstract.pl?ConfID=11&Number=1251)

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nicpottier
This is a neat idea and one I was both surprised and excited to find in the
app store when I was looking for such a thing. Sadly it fails in
implementation, it just doesn't work terribly well, I almost wonder if they
are just faking it and have some heavy bias to report 80 bpm, since that's
believe for most.

But in my experience at least, when you compare it to a real heart rate
monitor, it is always quite off.

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geuis
Bought it, was skeptical. However, it seems to perform as advertised. Compared
with a manual beat check and it was only off by a couple.

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ZeroGravitas
Seems to be the same tech as Nintendo's Wii Vitality sensor, according to this
summary of the patent:

[http://www.siliconera.com/2010/10/07/nintendo-patent-
shows-w...](http://www.siliconera.com/2010/10/07/nintendo-patent-shows-wii-
vitality-sensor-game-example/)

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dagw
It would be cool if someone with a real heart rate meter could run some tests
to see how accurate this is. For what it's worth, I couldn't get it to work.
The values fluctuated between 50-150 and refused to settle on any value.

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sounddust
Seems to work perfect for me; it reported 68, and I counted 66 manually (by
counting the number of beats myself in 10 seconds and multiplying by 6). For
reference, I have an iPhone 4 and it utilized the flash.

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JshWright
Only counting 10 seconds worth reduces your precision pretty substantially. I
generally count for a minimum of 15 seconds, with 30 being typical.

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sounddust
In any case, the software also shows a visual indicator of when it detects
that your heartbeat, and it graphs your heartbeat over time. It's obvious from
feeling your pulse while using it that it's correct, at least in my case with
my phone.

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yellowbkpk
If they're doing this correctly they could also tell you your blood oxygen
level. Blood Ox would be much more useful to a larger range of people.

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stretchwithme
how would that work? I can understand how pulse is detected, as you are
measuring the differences from second to another and finding a pattern. But
how would you know what correlates to a particular level of oxygen in a
particular person?

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tel
From what I've read it simply takes the ratio of absorbance from the systole
and diastole and considers that a stable non-linear estimator of %SpO2. The
device itself needs to be calibrated to get the non-linear fit in place, but
each individual is assumed to be (in gross measure) similar enough to get
meaning out of it.

Of course, there's going to be huge variation across finger types, blood
volumes, lighting conditions, placement. I wouldn't consider them to be
accurate much more than those impedance-based body fat percentage computers.
In both cases, huge discrepancies from healthy values are still telling
despite small-scale noise.

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stretchwithme
hmm, me thinks huge variations may be bigger than small-scale noise.

thanks.

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tel
Not to be contrary, but that's what I said.

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nutjob123
Does this really work? I wonder if it works with equal accuracy for people of
different color or skin types.

