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sound interpretation with bs2p40?? — Parallax Forums

sound interpretation with bs2p40??

ArchiverArchiver Posts: 46,084
edited 2004-05-20 12:30 in General Discussion
i posted a similar message before where most thought what i want to
do would require a lot more processing power. however i think it's
simpler than that, i think. i want to use the bs2p40 to distinguish
between two different sounds. one a boo, like boooo, and the other
is clapping. i would think a mic in line would work, and then set
frequency levels accordingly. obviously the boo would have a lower
frequency than a clap. so if someone clapped or booed, the stamp
would act as a switch and turn on or off an apparatus. any ideas.
part #'s possible software? thanks for any help. mark

Comments

  • ArchiverArchiver Posts: 46,084
    edited 2004-05-16 00:59
    Hi Mark,

    Unfortunatly, it's a little harder than you describe to recognize
    sounds. I'm not an expert so please bear in mind that I could be
    totally wrong but here is what I think you would need:

    1. Mic pre amp circuit before the Basic Stamp

    2. Analog to Digital convertor (not sure if stamps have them or
    not).

    3. One you sample the sound, you have to determine where the sound
    starts and stops then find the dominate frequencies using something
    like an FFT (Fast Fourier Transform).

    4.You would create a template of the sound to check and compare it
    against templates you had previously stored.

    It's not impossible but it's not simple either. I have some VCP200
    voice recognition chips around here somewhere (looking through desk
    drawers) that Radio Shack used to sell. They could determine 8 or
    so words with a pretty good accuracy but I haven't seen anything
    like these in years.

    Again, I've never done this and everything I just described could be
    wrong. Is there anyone else in here that know about speech or sound
    recognition?

    I have read of a simple speech recognition technique that looks at
    the total energy of the sound to recognize but I haven't tried it to
    see if it works. I'll see if I can write up a quick demo app if I
    get a chance.

    Ken
    http://www.speechchips.com

    --- In basicstamps@yahoogroups.com, "sponsitility"
    <markmcleod50@y...> wrote:
    > i posted a similar message before where most thought what i want
    to
    > do would require a lot more processing power. however i think it's
    > simpler than that, i think. i want to use the bs2p40 to
    distinguish
    > between two different sounds. one a boo, like boooo, and the other
    > is clapping. i would think a mic in line would work, and then set
    > frequency levels accordingly. obviously the boo would have a lower
    > frequency than a clap. so if someone clapped or booed, the stamp
    > would act as a switch and turn on or off an apparatus. any ideas.
    > part #'s possible software? thanks for any help. mark
  • ArchiverArchiver Posts: 46,084
    edited 2004-05-16 13:49
    Hi Mark,

    I would not go to FFT with a Stamp :-) but try some filterbanks.

    You could try a low pas filter RC whitch let's all frequency's below say 500
    Hz go through for the BOOOOO's. And then a high pass filter above say 2000
    Hz for the claps.

    And then you will have to detect these frequencies with the samp. An ADC
    might not be necessary as you could use the low/high level transition of an
    input on the Stamp. And some potmeters to adjeut the levels.

    Depending on the level of your input signal you may need an amplifier also.

    This will be far more easy to implement than the FFT route for which the
    Stamp is not powerfull enough anyway!

    I hope this helps.

    Klaus
    Original Message
    From: Ken <kenlem@m...>
    To: <basicstamps@yahoogroups.com>
    Sent: Sunday, May 16, 2004 1:59 AM
    Subject: [noparse][[/noparse]basicstamps] Re: sound interpretation with bs2p40??


    > Hi Mark,
    >
    > Unfortunatly, it's a little harder than you describe to recognize
    > sounds. I'm not an expert so please bear in mind that I could be
    > totally wrong but here is what I think you would need:
    >
    > 1. Mic pre amp circuit before the Basic Stamp
    >
    > 2. Analog to Digital convertor (not sure if stamps have them or
    > not).
    >
    > 3. One you sample the sound, you have to determine where the sound
    > starts and stops then find the dominate frequencies using something
    > like an FFT (Fast Fourier Transform).
    >
    > 4.You would create a template of the sound to check and compare it
    > against templates you had previously stored.
    >
    > It's not impossible but it's not simple either. I have some VCP200
    > voice recognition chips around here somewhere (looking through desk
    > drawers) that Radio Shack used to sell. They could determine 8 or
    > so words with a pretty good accuracy but I haven't seen anything
    > like these in years.
    >
    > Again, I've never done this and everything I just described could be
    > wrong. Is there anyone else in here that know about speech or sound
    > recognition?
    >
    > I have read of a simple speech recognition technique that looks at
    > the total energy of the sound to recognize but I haven't tried it to
    > see if it works. I'll see if I can write up a quick demo app if I
    > get a chance.
    >
    > Ken
    > http://www.speechchips.com
    >
    > --- In basicstamps@yahoogroups.com, "sponsitility"
    > <markmcleod50@y...> wrote:
    > > i posted a similar message before where most thought what i want
    > to
    > > do would require a lot more processing power. however i think it's
    > > simpler than that, i think. i want to use the bs2p40 to
    > distinguish
    > > between two different sounds. one a boo, like boooo, and the other
    > > is clapping. i would think a mic in line would work, and then set
    > > frequency levels accordingly. obviously the boo would have a lower
    > > frequency than a clap. so if someone clapped or booed, the stamp
    > > would act as a switch and turn on or off an apparatus. any ideas.
    > > part #'s possible software? thanks for any help. mark
    >
    >
    >
    >
    > To UNSUBSCRIBE, just send mail to:
    > basicstamps-unsubscribe@yahoogroups.com
    > from the same email address that you subscribed. Text in the Subject and
    Body of the message will be ignored.
    >
    > Yahoo! Groups Links
    >
    >
    >
    >
    >
    >
  • ArchiverArchiver Posts: 46,084
    edited 2004-05-16 16:25
    --- In basicstamps@yahoogroups.com, "sponsitility"
    <markmcleod50@y...> wrote:
    > i posted a similar message before where most thought what i want
    to
    > do would require a lot more processing power. however i think it's
    > simpler than that, i think. i want to use the bs2p40 to
    distinguish
    > between two different sounds. one a boo, like boooo, and the other
    > is clapping. i would think a mic in line would work, and then set
    > frequency levels accordingly. obviously the boo would have a lower
    > frequency than a clap. so if someone clapped or booed, the stamp
    > would act as a switch and turn on or off an apparatus. any ideas.
    > part #'s possible software? thanks for any help. mark

    I think you'll be better off using a speaker-independant speech
    recognition chip. Even that may not work the way you want, but it
    seems that what you want to do requires more signal processing in
    terms of audio than what you will be able to do directly with the
    BS2.

    Chris Savage
    Knight Designs
  • ArchiverArchiver Posts: 46,084
    edited 2004-05-16 21:10
    This is way too complicated for a stamp to process as a digitized audio
    signal, but you should be able to build a couple of analog band-pass
    filters, or even a high-pass and low-pass filter pair. Anything of
    sufficient amplitude below a given frequency (say 500 Hz) would trip a
    one-shot pulse generator (a 555), and anything above a given frequency (say
    1000 Hz) would trip the other one-shot.

    Mike Sokol
    mike@f...
    www.fitsandstarts.com

    " One should not increase, beyond what is necessary,
    the number of entities required to explain anything"...
    -William of Occam-

    > --- In basicstamps@yahoogroups.com, "sponsitility"
    > <markmcleod50@y...> wrote:
    > > i posted a similar message before where most thought what i want
    > to
    > > do would require a lot more processing power. however i think it's
    > > simpler than that, i think. i want to use the bs2p40 to
    > distinguish
    > > between two different sounds. one a boo, like boooo, and the other
    > > is clapping. i would think a mic in line would work, and then set
    > > frequency levels accordingly. obviously the boo would have a lower
    > > frequency than a clap. so if someone clapped or booed, the stamp
    > > would act as a switch and turn on or off an apparatus. any ideas.
    > > part #'s possible software? thanks for any help. mark
  • ArchiverArchiver Posts: 46,084
    edited 2004-05-20 02:28
    Mike,

    Do you have any links that would show such a circuit?

    Thanks,
    Ken
    www.speechchips.com

    --- In basicstamps@yahoogroups.com, "Mike Sokol" <mike@f...> wrote:
    > This is way too complicated for a stamp to process as a digitized
    audio
    > signal, but you should be able to build a couple of analog band-
    pass
    > filters, or even a high-pass and low-pass filter pair. Anything of
    > sufficient amplitude below a given frequency (say 500 Hz) would
    trip a
    > one-shot pulse generator (a 555), and anything above a given
    frequency (say
    > 1000 Hz) would trip the other one-shot.
    >
    > Mike Sokol
    > mike@f...
    > www.fitsandstarts.com
    >
    > " One should not increase, beyond what is necessary,
    > the number of entities required to explain anything"...
    > -William of Occam-
    >
    > > --- In basicstamps@yahoogroups.com, "sponsitility"
    > > <markmcleod50@y...> wrote:
    > > > i posted a similar message before where most thought what i
    want
    > > to
    > > > do would require a lot more processing power. however i think
    it's
    > > > simpler than that, i think. i want to use the bs2p40 to
    > > distinguish
    > > > between two different sounds. one a boo, like boooo, and the
    other
    > > > is clapping. i would think a mic in line would work, and then
    set
    > > > frequency levels accordingly. obviously the boo would have a
    lower
    > > > frequency than a clap. so if someone clapped or booed, the
    stamp
    > > > would act as a switch and turn on or off an apparatus. any
    ideas.
    > > > part #'s possible software? thanks for any help. mark
  • ArchiverArchiver Posts: 46,084
    edited 2004-05-20 12:30
    Ken,

    For those of you that don't remember the 60's, we had a groovy lighting
    controller that would blink different color lights for bass, midrange, and
    treble frequencies. FAR... OUT...!!!!

    I think what you can do is hack the filters from a color organ circuit to
    trigger separate outputs on a "clap" or a "boo". See
    http://www3.telus.net/chemelec/Projects/Color-Organ/Color-Organ-2.jpg

    You need to eliminate the direct A.C. power supply and run the LM324
    OpAmp off the Stamp's 5 volt supply on pin 4 so the LM324 outputs swing
    between .6 volts and 4.4 volts and send that to a 555 in one-shot mode. At
    least as I remember an LM324 will get within .6 volts of the power supply
    rails. Any other stampers please correct me if I'm wrong. Yes, I grew up and
    learned electronics in the 60's...

    Here's one example of 555 timer circuits:
    http://ourworld.compuserve.com/homepages/Bill_Bowden/page9.htm
    I'm sure there's about a million other versions on the web, but that's the
    idea. Then use the 555 one-shot to drive the I/O pins on the Stamp.

    You probably only need the filter circuits for the high-pass and low-pass
    sections, then use one section of the LM324 to amplify the output of a Radio
    Shack electret mic element which should cost a buck or two at most.

    Mike Sokol
    mike@f...
    www.fitsandstarts.com


    " One should not increase, beyond what is necessary,
    the number of entities required to explain anything"...
    -William of Occam-


    Original Message
    From: "Ken" <kenlem@m...>
    To: <basicstamps@yahoogroups.com>
    Sent: Wednesday, May 19, 2004 9:28 PM
    Subject: [noparse][[/noparse]basicstamps] Re: sound interpretation with bs2p40??


    > Mike,
    >
    > Do you have any links that would show such a circuit?
    >
    > Thanks,
    > Ken
    > www.speechchips.com
    >
    > --- In basicstamps@yahoogroups.com, "Mike Sokol" <mike@f...> wrote:
    > > This is way too complicated for a stamp to process as a digitized
    > audio
    > > signal, but you should be able to build a couple of analog band-
    > pass
    > > filters, or even a high-pass and low-pass filter pair. Anything of
    > > sufficient amplitude below a given frequency (say 500 Hz) would
    > trip a
    > > one-shot pulse generator (a 555), and anything above a given
    > frequency (say
    > > 1000 Hz) would trip the other one-shot.
    > >
    > > Mike Sokol
    > > mike@f...
    > > www.fitsandstarts.com
    > >
    > > " One should not increase, beyond what is necessary,
    > > the number of entities required to explain anything"...
    > > -William of Occam-
    > >
    > > > --- In basicstamps@yahoogroups.com, "sponsitility"
    > > > <markmcleod50@y...> wrote:
    > > > > i posted a similar message before where most thought what i
    > want
    > > > to
    > > > > do would require a lot more processing power. however i think
    > it's
    > > > > simpler than that, i think. i want to use the bs2p40 to
    > > > distinguish
    > > > > between two different sounds. one a boo, like boooo, and the
    > other
    > > > > is clapping. i would think a mic in line would work, and then
    > set
    > > > > frequency levels accordingly. obviously the boo would have a
    > lower
    > > > > frequency than a clap. so if someone clapped or booed, the
    > stamp
    > > > > would act as a switch and turn on or off an apparatus. any
    > ideas.
    > > > > part #'s possible software? thanks for any help. mark
    >
    >
    >
    >
    > To UNSUBSCRIBE, just send mail to:
    > basicstamps-unsubscribe@yahoogroups.com
    > from the same email address that you subscribed. Text in the Subject and
    Body of the message will be ignored.
    >
    > Yahoo! Groups Links
    >
    >
    >
    >
    >
    >
    >
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