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FingerIO: Using Active Sonar for Fine-Grained Finger Tracking

fingerio.cs.washington.edu

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Re: FingerIO: Using Active Sonar for Fine-Grained Finger Tracking

#81

Post by jgrahamc »

fudged71 wrote: post #71
jgrahamc wrote: post #70

Earlier quoted context omitted.

Did you ask? Many years ago I decided to reproduce an algorithm used to detect copy/paste image modification. http://blog.jgc.org/2008/02/tonight-im-going-to-write-myself... The researcher was happy to provide me with their test images to verify that my implementation worked. Try asking.

Have you considered providing this tool as a service? It would be great to easily detect forgeries without CLI experience.

No. I wrote that 8 years ago, I've open sourced the code, anyone who wants to take it and run with it can. It's too much work for me to maintain a system that would do this for people.

Re: FingerIO: Using Active Sonar for Fine-Grained Finger Tracking

#82

Post by nly »

My intuition tells me this just doesn't hold water with respect to information theory.. i.e. the number of bits of useful information about a finger you can pull from a microphone. Putting aside human digits, has anyone even demonstrated that you can reliably detect an eighteen-wheeler rig moving toward a phone with this technique? And what about the range of the speaker? Complete nonsense.

Re: FingerIO: Using Active Sonar for Fine-Grained Finger Tracking

#83

Post by et2o »

nly wrote: post #82

My intuition tells me this just doesn't hold water with respect to information theory.. i.e. the number of bits of useful information about a finger you can pull from a microphone. Putting aside human digits, has anyone even demonstrated that you can reliably detect an eighteen-wheeler rig moving toward a phone with this technique? And what about the range of the speaker? Complete nonsense.

Are you suggesting the video is fake? I think your intuition is wrong.

To address your comment more directly, I don't see any information theory type limit immediately applicable here for finding xyz coordinates using echolocation. That's done in a variety of contexts.

Re: FingerIO: Using Active Sonar for Fine-Grained Finger Tracking

#84

Post by knughit »

saulrh wrote: post #77
magic_man wrote: post #14

I work with sonar and the physical positioning of the sensors is important in trying to get useful results. Why is it these academic types don't release the apks or software? Just publications and maybe a video.

Having been in this kind of situation before: because the software isn't ready for any kind of release. They probably spent a week gathering and tuning the parameters on the DSP for each individual phone they ran it on, and without their knowledge of the system it'd take you a month and a half to get it working on your phone.

If they are publishing a paper, their methods (including custom source code) are ready for release for peer review. Ftheit software sucks, thet should not rely on it for scientific results.

Re: FingerIO: Using Active Sonar for Fine-Grained Finger Tracking

#85

Post by candu »

nly wrote: post #82

My intuition tells me this just doesn't hold water with respect to information theory.. i.e. the number of bits of useful information about a finger you can pull from a microphone. Putting aside human digits, has anyone even demonstrated that you can reliably detect an eighteen-wheeler rig moving toward a phone with this technique? And what about the range of the speaker? Complete nonsense.

Your intuition is probably wrong: off-the-shelf consumer-grade microphones can typically gather 44.1-96k samples per second at 16-24 bits per sample. That's a lot of potential information.

Also, consider that your ear/brain apparatus estimates object positions and occlusions from audio signals all the time.

Also also, the eighteen-wheeler problem is vastly different from the finger problem, as the latter is smaller, slower, and closer to the microphone, each by 1-2 orders of magnitude.

Re: FingerIO: Using Active Sonar for Fine-Grained Finger Tracking

#86

Post by rhema »

nly wrote: post #82

My intuition tells me this just doesn't hold water with respect to information theory.. i.e. the number of bits of useful information about a finger you can pull from a microphone. Putting aside human digits, has anyone even demonstrated that you can reliably detect an eighteen-wheeler rig moving toward a phone with this technique? And what about the range of the speaker? Complete nonsense.

From an information theory perspective, think about the number of samples. Even 22Khz yields a tremendous number of individual points.

Re: FingerIO: Using Active Sonar for Fine-Grained Finger Tracking

#88

Post by aiabgold »

jstapels wrote: post #24

I wonder how accurate it really is. The demo video didn't match up with the movements at all and the on-screen drawings looked like prerecorded video that they were trying to sync to. It's a neat idea, but without a dedicated component or an extremely high-speed RTOS, you're not going to come close to the level accuracy that's really needed to do the math and still allow interaction. I don't mean to rain on the parad…

> I just don't think they really have anything usable.

I'm not sure that's the purpose. I wouldn't think of this as being intended to be a fully usable product right now. They could be intending it merely as an interesting experiment to explore new possibilities for interaction with mobile and wearable tech.

Another CS student came up with a virtual keyboard using the iPhone's accelerometer[1]. It only had ~80% accuracy[2], so was it all that useful or practical? Probably not. But could it lead to another person or company refining the technique for production in the future? Certainly.

[1] Video: https://vimeo.com/49780741

[2] http://www.gottabemobile.com/2012/11/13/cs-student-turns-iph...

Re: FingerIO: Using Active Sonar for Fine-Grained Finger Tracking

#89

Post by nmrm2 »

knughit wrote: post #84
saulrh wrote: post #77

Earlier quoted context omitted.

Having been in this kind of situation before: because the software isn't ready for any kind of release. They probably spent a week gathering and tuning the parameters on the DSP for each individual phone they ran it on, and without their knowledge of the system it'd take you a month and a half to get it working on your phone.

If they are publishing a paper, their methods (including custom source code) are ready for release for peer review. Ftheit software sucks, thet should not rely on it for scientific results.

Product development isn't actually the purpose of science.

Re: FingerIO: Using Active Sonar for Fine-Grained Finger Tracking

#90

Post by k__ »

Ultrasound tracking is always problematic, because of all the noise.

I have the feeling, every few years someone has the idea again, to use ultrasound for something and it starts promising, but then the accuracy and lag doesn't go away and dogs and cats go wild.

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