On Mon, Apr 14, 2008 at 3:33 AM, Fabian Olesen <[EMAIL PROTECTED]> wrote:
> > > On Mon, Apr 14, 2008 at 2:57 AM, Hans L <[EMAIL PROTECTED]> wrote: > > > > > The standard tones allow up to 16 values to be represented at a time, > > so it would be like transferring data in base16 (aka hex or 4 bits at > > a time). According to wikipedia, the minimum length of a tone should > > be 70ms, which would limit data transfer to roughly 56 bits/second. > > Of course this is very slow and unusable if you are thinking in terms > > of web browsing, but could be useful for transmitting small amounts of > > data such as URIs or other connection information(an IP address is > > only 32bits). The URIs could be accessed immediately if the receiving > > end has a simultaneous internet connection, or saved for later. > > > This could actually work > > But it would require that both ends have a specialised phonestack > (openmoko fx) > where some kind of protocol was inplemented for listening for DTMF with a > start and stop signal, > where the phone would know not to send the tones into the ear piece, > so that it would not scream into the other user's ears. > > after a little research, i came across the Goertzel algorithm (Wikipedia link) <http://en.wikipedia.org/wiki/Goertzel_algorithm%20> -- Mvh Fabian Olesen ---- If it moves, compile it.
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