5:20 AM
@A_A the FFT seems to be quite noisy, with a relatively strong peak still around 50 bpm.. in fact, sometimes, my program still prints around 50 bpm, but mostly prints around 70-74 bpm, which is close to my heart rate...
6:03 AM
2 hours later…
8:12 AM
@A_A it seems from repeated experiments, that good lighitng and still face can improve SNR (as expected i guess), but the 50 bpm signal still occasionally shows up... I still want to figure where that is coming from and try to remove it and how to improve the SNR because other papers seem to have really good SNR, and cleaner FFT spectra...
1 hour later…
9:15 AM
2 hours later…
11:48 AM
11 hours later…
10:28 PM
@A_A I am at an airport, so the lighting is bad, and overall lots of noise ... but the signal is there at 1.2 Hz... but i guess the flicker might not be the problem...
@A_A ok so for the intensity experiment, I kept everything the same as the previous experiments (i.e. spatial avg. of each color channel, no normalization or bandpass), except after obtaining the RGB temporal signals, I averaged them as you specified, and did the FFT (so no ICA like you said)... I got weird results... for one, the heart rate signal did not show up at all:
@A_A given that I am doing this in an airport, with my laptop on my lap and not on a table, there were some sudden changes due to slight movement, travelers bumping into me, etc... so I guess take these results with a grain of salt? but they aren't that bad, so hopefully we can conclude something from these plots...
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Apr '1818
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Discussion between A_A and TanMath
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