DTMF detection through Sound Card

Started by dkurman in comp.dsp13 years ago 4 replies

Hi. I have posted two messages, but I can?t get this working. I mean, I'm getting the buffer from the sound card, and then I perform the...

Hi. I have posted two messages, but I can?t get this working. I mean, I'm getting the buffer from the sound card, and then I perform the goertzel algorithm with this, but the data I get is wrong almost all times. The steps are: Data: Buffer Size: 4096 Kb, N=4096, Sample Rate = 22050, Format: 16 bits 1) When I get the buffer completely filled, I read the buffer (two bytes a time) convertin...


narrow band detector for telephones

Started by pal.debabrata123 in comp.dsp12 years ago 2 replies

Hello guys, I was going through Steves comments about narrow band detector in dsprelated.com ,i.e. using auto correlation and finding...

Hello guys, I was going through Steves comments about narrow band detector in dsprelated.com ,i.e. using auto correlation and finding peaky_ness. The sources of these tone signal are 1) Echo of dial tone ( which is a amplitude modulated signal , 400 hz being modulated by 25 hz) 2) a dtmf tone ( may be as high as 0 dbm ) 3) may be echo of other tones 4) or a whistle may be from the talker ( I...


Goertzel Algorithm

Started by mahsad in comp.dsp10 years ago 20 replies

Hello, I am implementing DTMF detection using Goertzel Algorithm this is my program on C54x; ******************************************** * ...

Hello, I am implementing DTMF detection using Goertzel Algorithm this is my program on C54x; ******************************************** * main program ******************************************** #include "(781 Hz & 1218 Hz).h" //my input=sum //of two sinusoidal with 781 Hz & 1218 Hz #define abs(i) (i)


Re: Wave filter question (mainly for Joerg)

Started by Nico Coesel in comp.dsp13 years ago

Tim Wescott wrote: > Joel Kolstad wrote: > > Simple question on wave filters, that I've heard about but never used: Rumor > > has it...

Tim Wescott wrote: > Joel Kolstad wrote: > > Simple question on wave filters, that I've heard about but never used: Rumor > > has it that wave filters are just the digital simulation of a classical L-C > > (ladder-type) filter structure. True? > > > > I skimmed the TI application note on DTMF detection using wave filters, and > > there's an awful lot of unfamiliar (to


Re: VOIP, Call Center, and DTMF errors...

Started by David Morgan (MAMS) in comp.dsp12 years ago

"David Morgan (MAMS)" wrote in message news:Q4fUh.3418$h8.2551@trnddc06... > > "Richard Crowley" wrote in...

"David Morgan (MAMS)" wrote in message news:Q4fUh.3418$h8.2551@trnddc06... > > "Richard Crowley" wrote in message news:1322seppkmblh0a@corp.supernews.com... > > "David Morgan (MAMS)" wrote... > > > "Richard Crowley" wrote ... > > > > "David Morgan (MAMS)" wrote ... > > > > > "Mark" wrote ... > > > > > > > > > > > > > > > It seems that the call i