Comment Re:Voiceprints a much better alternative (Score 1) 254
A very common question. Permit me to intrude further into this thread with some more information, and I'll also try to relate it to facial recognition.
"What if I have a cold?" --> Voiceprints measure behavioral characteristics of the voice, as well as physical characteristics of the person's vocal track, which don't change when hoarse or nasal. (Facial recognition also uses a combination of characteristics such that adding a beard or glasses will just raise or lower the confidence level of the identification)
I'll pre-empt the other two most common questions:
"What about impostors using a recording of my voice?" --> Analog-to-Digital recording, followed by Digital-to-Analog playback through the speaker, results in degraded data insufficient to match the voiceprint. High-end recording equipment fooling the system is eliminated by using "something you know" information and liveness testing -- in other words, asking the person to repeat numbers, words, or phrases that aren't introduced in advance.
"What about impressionists imitating me?"
Voiceprints capture more voice features than mimics can copy, so they are not easily tripped-up by impressionists.
I imagine facial recognition has a similar story, that masks and disguises are unlikely to trip up the systems, though they would certainly lead to more false rejections.
In the end, multiple factors ("what you have" or "what you know") are required to ensure better security for any biometrics, just as face recognition should never just be about the face. The other key component is determining level of security -- tuning parameters for an acceptably low False Accept rate (we don't let ANYONE in) vs. a False Reject rate (but we don't want to inconvenience our customers). Backup security is helpful to have in case of false rejects... just like being directed to an operator when you forget your over-the-phone PIN.
Hmmm, sorry, this IS slashdot, was I supposed to throw in some cynical comment in here too?
"What if I have a cold?" --> Voiceprints measure behavioral characteristics of the voice, as well as physical characteristics of the person's vocal track, which don't change when hoarse or nasal. (Facial recognition also uses a combination of characteristics such that adding a beard or glasses will just raise or lower the confidence level of the identification)
I'll pre-empt the other two most common questions:
"What about impostors using a recording of my voice?" --> Analog-to-Digital recording, followed by Digital-to-Analog playback through the speaker, results in degraded data insufficient to match the voiceprint. High-end recording equipment fooling the system is eliminated by using "something you know" information and liveness testing -- in other words, asking the person to repeat numbers, words, or phrases that aren't introduced in advance.
"What about impressionists imitating me?"
Voiceprints capture more voice features than mimics can copy, so they are not easily tripped-up by impressionists.
I imagine facial recognition has a similar story, that masks and disguises are unlikely to trip up the systems, though they would certainly lead to more false rejections.
In the end, multiple factors ("what you have" or "what you know") are required to ensure better security for any biometrics, just as face recognition should never just be about the face. The other key component is determining level of security -- tuning parameters for an acceptably low False Accept rate (we don't let ANYONE in) vs. a False Reject rate (but we don't want to inconvenience our customers). Backup security is helpful to have in case of false rejects... just like being directed to an operator when you forget your over-the-phone PIN.
Hmmm, sorry, this IS slashdot, was I supposed to throw in some cynical comment in here too?
