Who knows this type of filter

Started by Anonymous in comp.dsp7 months ago 3 replies

Hi everyone, I've got only formula for filter and seeking for how to calculate coefficients: Do this code for every incoming sample in t1...

Hi everyone, I've got only formula for filter and seeking for how to calculate coefficients: Do this code for every incoming sample in t1 = dyn - in*c1 dyn = in + t1*c1 t2 = t1* c2 out = t2 + in* c3 dyn should be 0 at first sample i think c1,c2,c3 are coefficients t1,t2 and dyn are temporaries This suppose to be shelving filter and parameters are ...


OT: Who invented the airfoil?

Started by Rune Allnor in comp.dsp7 months ago 31 replies

Hi all. This is one of those questions that just popped into my mind last night: Who invented / discovered the airfoil? Like in...

Hi all. This is one of those questions that just popped into my mind last night: Who invented / discovered the airfoil? Like in aviation history. I know the Montgolfiers discovered the balloon, the Wright did the first powered flight and so on, but who was the first to describe the airforil as a component for 'heavier-than-air' flight? Lilienthal used devices very similar to what we t...


Sallen Key

Started by RichD in comp.dsp7 months ago 4 replies

Reviewing some old stuff, I crossed the Sallen-Key filter. Analysis of this topology is relatively straightforward, but what I never sussed...

Reviewing some old stuff, I crossed the Sallen-Key filter. Analysis of this topology is relatively straightforward, but what I never sussed is the why - what makes it so important? What was the great advance, at that time? And is it still considered so consequential, today? -- Rich


Better watch out, better not cry, better not pout...

Started by RichD in comp.dsp7 months ago 2 replies

.... I'm telling you why... Donald Knuth is coming to town! His annual Xmas Tree lecture. Yessir, the biggest event on the digital...

.... I'm telling you why... Donald Knuth is coming to town! His annual Xmas Tree lecture. Yessir, the biggest event on the digital calendar, Dec. 4, 6:30 PM, PST. Not to be missed by any nerd, geek, or those who aspire to such felicity. 'tree' is literal, as Knuth is the Duke of Graph Theory. Hand him any problem, he'll convert to a graph model, and go from there. There may n...


Attention FDLS Fans ...

Started by Greg Berchin in comp.dsp7 months ago 1 reply

I've been laid-up for the past week or so, recovering from surgery, so I used the time to create a variant of Frequency Domain Least Squares...

I've been laid-up for the past week or so, recovering from surgery, so I used the time to create a variant of Frequency Domain Least Squares (FDLS) inspired by this ancient comp.dsp thread: https://groups.google.com/d/msg/comp.dsp/MOD86bo829Y/2BAVHOxK_yQJ Whereas standard FDLS takes a magnitude/phase frequency response and attempts to create a transfer function that matches it, "FDLS Allpas...


Overcomplete Matching Pursuit with Gammatones

Started by MatthewA in comp.dsp8 months ago

Inspired by Smith/Lewicki’s overcomplete matching pursuit, I’m looking to put together “spikegrams” starting with Gammatones...

Inspired by Smith/Lewicki’s overcomplete matching pursuit, I’m looking to put together “spikegrams” starting with Gammatones using matching pursuit. The problem I’m coming up against in the major Matching Pursuit libraries (mptk, wmpalg, scilearn) is that they ask for discreet atoms and Gammatones are parameterized with attack, decay and phase


Nomenclature Question

Started by Greg Berchin in comp.dsp8 months ago 1 reply

We describe phase response as "minimum phase", "linear phase", etc. Is there a name for a phase response in which the group delay is everywhere...

We describe phase response as "minimum phase", "linear phase", etc. Is there a name for a phase response in which the group delay is everywhere nonnegative? Thanks, Greg


MELP speech compression

Started by karel bruneel in comp.dsp8 months ago 2 replies

Hi, Can someone pleas help me find the folowing article: "Analog to Digital Conversion of Voice by 2,400 Bit/second Mixed Excitation Linear...

Hi, Can someone pleas help me find the folowing article: "Analog to Digital Conversion of Voice by 2,400 Bit/second Mixed Excitation Linear Prediction (MELP)," Federal Information Processing Standards Publication (FIPS PUB) Draft, June 12, 1997 I?me just a poor student not able to pay 35$ for an article. Thank you Karel Bruneel


Melp1200 data memory

Started by staseer in comp.dsp8 months ago 3 replies

Hi, I have downloaded a melp1200 c code from the internet and am trying to port it adsp-2188. There is an array declared in qnt12_cb, by the name...

Hi, I have downloaded a melp1200 c code from the internet and am trying to port it adsp-2188. There is an array declared in qnt12_cb, by the name of res256x64x64x64 which has a size of 0x2300. The maximum segment which I can define is of 8k. I am using overlays. Is there a way to fit this array into the memory without decomposing it??? Other wise I will have to make segments of this array and k...


MELP Test Vectors

Started by Anonymous in comp.dsp8 months ago 10 replies

Hi, I am looking for MELP test vectors to verify my implementation. Can someone point me in the right direction? I expected they would be...

Hi, I am looking for MELP test vectors to verify my implementation. Can someone point me in the right direction? I expected they would be easy to find - considering the DDVPC have 3 publically available MELP implementations - but I can not find test vectors anywhere. Regards, Nick


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