cellphones as room bugs

[John Levine]

>8Kbit/second is enough if all you need is to understand what is being
>said, not recognize the speaker.  The processing power to do this is
>pretty small on today's scale of things.)

With decent compression techniques, 8kbps is close to telephone
quality, and 2400bps has artifacts but is still quite clear.  There
are some nice examples at:

http://www.data-compression.com/speech.shtml

1kbps would be adequate for understandable speech, so I would expect
that a modern phone with megabytes for music storage could easily
store several days of voice-activated room bugging.

R's,
John

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