similar to: MDF filter coefficients

Hello, I want to know if two quadratic regressions are significantly different. I was advised to make the test using step 1 bootstrapping both quadratic regressions and get their slope coefficients. (Let's call the slope coefficient *â*^1 and *â*^2) step 2 use the slope difference *â*^1-*â*^2 and bootstrap the slope coefficent step 3 find out the sampling distribution above and

Hi, Given a data frame: df1: application id (appid), project id (pid), person months (pm), function points (fp) How do I produce linear modelling results at the appid level. That is, I would like to find the coefficent and intercept for the formula "pm ~ fp" for each application. Thanks

Hi all, I am trying to teach myself to use and program R (How else do you do it? lol) Anyway, I wrote a piece of code to compute coefficent alpha for a scale. As I am neither a statistician nor a programmer, I wanted people's feedback. The code appears to work (Win 95 with R 1.0.1) and I have verified my result with SPSS and it was correct (much to my astonishment!). Nonetheless, I am

Dear list, I've tried several times to wrap my head around the Design library, without much success. It does some really nice things, but I'm often uncomfortable because I don't understand exactly what it's doing. Anyway, one thing I really like is the latex.ols() function, which converts an R linear model formula to a LaTeX equation. So, I started writing a latex.lm() function

Hi I just upgraded to http://svn.xiph.org/trunk/speex r10357 and got this build warning: alfredh@io:$ make -s mdf.o libspeex/mdf.c: In function 'speex_echo_cancel': libspeex/mdf.c:321: warning: statement with no effect libspeex/mdf.c:317: warning: `adapt_rate' might be used uninitialized in this function Is this intentional? In any case here is a simple fix: Index:

Hello... I want to ask you something about your software implementation of MDF filter with DTD machanism. (mdf.c speex_echo.h files) My questions are: 1. What are theoretical (using in your articles) equivalents of index symbols from your program? 2. Could you describe or give me an algorith which was using during software implementation of the MDF+DTD 3. How I could freeze MDF by means of DTD

The latest SVN version breaks mdf.c when running without fixed point. Patch: Index: mdf.c =================================================================== --- mdf.c (revision 10563) +++ mdf.c (working copy) @@ -169,6 +169,8 @@ acc[i+1] += (X[i+1]*Y[i] + X[i]*Y[i+1]); } acc[i] += X[i]*Y[i]; + X += N; + Y += N; } } #endif

Hi, I made a small error in the impulse reponse function; when doing the inverse fft in fixed point, it will overflow unless it's properly scaled. This patch uses the same scaling as that used when updating the filters, and the outputs now have the same shape and the same scale in fixed and floating point. Best regards, Thorvald -------------- next part -------------- diff -ubBwr

Hi, I have a very large ".mdf" database (36 GB) that I want to import to R. I'm using a computer with 64 GB of RAM, running on windows server 2008 R2 with SQL. Could anyone guide me through the process. I have absolutely no idea what to do. Thanks, Mauricio Romero [[alternative HTML version deleted]]

Hi, I'm still trying to implement speex AEC into my VOIP project and I have some problrm with MDF filter response. I have plots of ref(near-end), y(filter response) signals and from plots I obtain that filter response is to small so when i substruct it from ref signal there is no efect. Is there any way to make filter giving response about ref signal amplitude? /Przemek Stajniak.

Did a bit of tuning in SVN. Could you try that? What frame size, filter length, sampling rate are you using? All the process you describe is actually the tip of the iceberg I think. There is something making the adaptation diverge, which causes Eh and Yh to be large and so on. The part I changed is probably the one causing divergence. If it doesn't work, reducing the coefficients even more

Jean Marc, I ran across the silence issue that results from the echo canceller producing "bad" floating point data. Unfortunately this hasn't been done in a way i can reproduce, but I found that calling reset didn't fix the silence, unless I also reset: st->PHI[i] st->Eh[i] st->Yh[i] So it may be good to add these to the reset function. I was using these in

> Generate a test signal (10+x sine waves per frame), where x increases by > one for each iteration, and wraps around at 100. Testing with sine waves is usually not a good idea. If you intend on cancelling speech, then test with speech. > First off, it seems W is stored 'backwards'. The first values are for the > oldest frame, ok :) right. > However, when peeking at the

>> I'll need to add support for saving audio to my program, so I can give you >> the "actual" sampled loudspeaker and mic files, and I'll also need to get >> hold of a test person again. (I had a friend with a friend who has an >> exceptionally clear voice. My own "aaaaaa" is far too muddy to cause >> this). I'll try to get this done

Jean-Marc Valin <Jean-Marc.Valin@USherbrooke.ca> wrote: > > > Anyway, I found a few papers on multisource echo cancellation. Unless it's > > already a feature on the short-term "TODO" list, I'll take a stab at > > adding simple multisource cancelling after christmas. > > Multi-channel echo control is the subject of my post-doc and it will >

Jean Marc, Ok so I tested with the new code, same result- frame size= 160, filter length=160 ms/1280 samples, 8000 Hz diverged after 9564 calls/packets or 191 seconds. My system stays relatively in synch but is not perfect- difficult to measure if there is any clock drift, but it probably is. In order to make it break faster I use an open air usb microphone that is part of a logitech notebook

Jean Marc & list, Following up on this- there seems to be an issue with this calculation in mdf.c (Smooth echo energy estimate over time) Pey += Eh*Yh; Pyy += Yh*Yh; it goes too large for floating point, which seems to be caused by extremely large values in st->Rf[j], st->Yf[j] and smaller values in st->Eh[j], st->Yh[j]- things were relatively quiet

> Err. Ok, as I got it, 'bin 0' has it's amplitude in W[0], bin 1 to N-1 has > it's real part in W[i*2-1] and it's imag in W[i*2], and finally the > nyquist amplitude is in W[N-1] Not quite, it's packet "real, real, imag, real, imag, ...". > I took this from how power_spectrum() computes, so I might be off :) But power_spectrum() handles that

> Actually, computing the "power spectrum" for each frame of W shows > how large an ammount of the original signal at time offset j the > echo canceller thinks should be removed from the current input frame. Careful when looking at W because of how the real and imaginary parts are packed in the array. > If you compute W*X for each j and ifft, you'll get the >

Hi, Here's the second attempt of a patch to get the impulse response from the echo canceller :) -------------- next part -------------- diff -ubBwr clean/include/speex/speex_echo.h get_impulse/include/speex/speex_echo.h --- clean/include/speex/speex_echo.h 2007-10-09 13:08:15.000000000 +0200 +++ get_impulse/include/speex/speex_echo.h 2008-02-12 23:58:11.000000000 +0100 @@ -51,6 +51,14 @@