sadlah@yahoo.com.sg wrote:> Hi guys. Thanks a lot for the excellent replies. This is actually a > Senior Design class and we were assigned to do a project on DSP. Since > we have National Instrument's Speedy-33 board, it would be easier to > interface with it with Labview. What we're trying to build here is a > home security system that monitors(through microphones) a glass panel > to see if a break-in occurs. > > I guess what I wanted to know is if there is a specific pattern for the > input that i will be getting off the microphone. because i think the > generated waveform really depends on how hard i hit it or even the > position on the glass where the initial hit occured. > > More specifically, how can I use Labview to achieve this? Or what type > of signal processing would I have to undertake? I would say the > timeline that I have is about 2 months.Why not break some glass, record the sound, and analyse it? Leon
Detect sound of breaking glass
Started by ●February 21, 2006
Reply by ●February 22, 20062006-02-22
Reply by ●February 22, 20062006-02-22
"Leon" <leon_heller@hotmail.com> writes:> > Why not break some glass, record the sound, and analyse it? >Because he'll just be analyzing that particular window of that particular glass at that particular time breaking. :-) Ciao, Peter K. -- "And he sees the vision splendid of the sunlit plains extended And at night the wondrous glory of the everlasting stars."
Reply by ●February 22, 20062006-02-22
Peter K. wrote:> "Leon" <leon_heller@hotmail.com> writes: > > > > > Why not break some glass, record the sound, and analyse it? > > > > Because he'll just be analyzing that particular window of that > particular glass at that particular time breaking. :-)So that he can get some idea of the characteristics of the sound. He can then develop a suitable sytem, perhaps using neural nets, once he has identified the relevant parameters. He'll need a lot of glass if he does it that way. 8-) Leon
Reply by ●February 22, 20062006-02-22
"Leon" <leon_heller@hotmail.com> writes:> So that he can get some idea of the characteristics of the sound. He > can then develop a suitable sytem, perhaps using neural nets, once he > has identified the relevant parameters.Sorry, Neutral Notworks don't work for me. :-)> He'll need a lot of glass if he does it that way. 8-):-) Training over 100,000 epochs, yes, that is quite a bit! Ciao, Peter K. -- "And he sees the vision splendid of the sunlit plains extended And at night the wondrous glory of the everlasting stars."
Reply by ●February 22, 20062006-02-22
Peter K. wrote:> "Leon" <leon_heller@hotmail.com> writes: > > >>Why not break some glass, record the sound, and analyse it? >> > > > Because he'll just be analyzing that particular window of that > particular glass at that particular time breaking. :-) >If the system really has to detect the acoustic sound, the neural net approach is pretty obvious (despite the info that someone has seen fit to patent it). For a training set, there are several online sources of sound effects, as a Google search will demonstrate. For example, this site: http://www.sounddogs.com has a whole category of glass sounds. An alternative "advanced" strategy would be to identify the MPEG-7-style sound descriptors for breaking glass, and apply those to any detected sounds above the threshold level. The sensitivity of the detector will have to be carefully set, as breaking-glass sounds may leigitmately crop up in the home not least via the TV, or even the CD player. There is a famous breaking-glass sample in "Babooshka" by Kate Bush (or maybe breaking plates, not sure!); it would be a pity if the alarm was triggered by a moment of musical nostalgia, or by Bruce Willis in full surround sound mayhem. Richard Dobson