## Forums More comp.dsp

## Fourier Series

inWe all know that if you have an even function you have only cosine terms an= d an odd function only sine. When the function is neither even nor...

We all know that if you have an even function you have only cosine terms an= d an odd function only sine. When the function is neither even nor odd you = get both, or do you? This suddenly struck me. Suppose you have=20 f(x)=3Dsin(x) - this is odd since f(-x) =3D -f(x) f(x)=3Dsin(x)+1 is neither even nor odd. Now f(-x) ne -f(x) But this is just a dc level shift. Could you not therefo...

## How to change a voice's pitch in real time?

inI just learned how to convert an audioclip from a 33.3 rpm vinyl record to 78 rpm,...

I just learned how to convert an audioclip from a 33.3 rpm vinyl record to 78 rpm, here: https://community.adobe.com/t5/audition/converting-33-recording-to-78-how/td-p/9448709?page=1 What I need is similar but probably harder. I am developing a web application based on a segment from a 2013 TV program. Only the first seconds are relevant: https://www.youtube.com/watch?v=8MF04X2aLBw T...

## deriving freq-to-midi from harmonic series?

inForgive the ramble but I don't have to problem pinned down completely: I'm curious about the mathematical relationship between the harmonic...

Forgive the ramble but I don't have to problem pinned down completely: I'm curious about the mathematical relationship between the harmonic series= and equal temperament. I'd like to write a program that quantizes glissa= ndos into the harmonic series similar to birdsong but, of course, by defini= tion, you can't transition between equal tempered intervals with the harmon= ic series. =20...

## Simulation of Aliasing

inI ran across a problem in a DSP book that got me to thinking (the best kind= of problem). The author suggests that we can illustrate aliasing...

I ran across a problem in a DSP book that got me to thinking (the best kind= of problem). The author suggests that we can illustrate aliasing by sampl= ing an audio signal at a high frequency and then replacing samples with zer= oes to get a lower effective sampling frequency. For example, if we sample= at fs1 =3D 32 kHz and then keep every M =3D 4th sample (replacing the othe= r samples ...

## What's the deal with all the Italian posts?

inHi. I don't know about you guys but I think none of the below Italian posts= are related to DSP. What do you think? I copied a few sentences...

Hi. I don't know about you guys but I think none of the below Italian posts= are related to DSP. What do you think? I copied a few sentences from one o= f the posts and pasted it into a "translate" web page. The translation into= English was: "MASONAL-CRIMINAL LAW FIRM, ALWAYS ONE WITH MEGA ASSASSINS OF MAFIA, CAMORR= A, NDRANGHETA AND AS PER ITS SPECIALITY PUGLIA, EVEN MORE THAN SACRED U...

## Matlab finally fix AMD CPU performance

https://www.tomshardware.com/news/matlab-update-amd-cpu-performance-fix I guess it was forced on them by AMD CPUs taking over the market. Or...

https://www.tomshardware.com/news/matlab-update-amd-cpu-performance-fix I guess it was forced on them by AMD CPUs taking over the market. Or AMD users turning to Octave/Julia/Scilab

## COVID and statistics

inI hope everyone is well. This one is long and possibly boring. Since now we are apparently all epidimologists I thought I'd give it a try...

I hope everyone is well. This one is long and possibly boring. Since now we are apparently all epidimologists I thought I'd give it a try along with everyone else. And I have three technical questions in the below. USA total, and USA by state statistics are available at the COVID Tracking Project among other places. I've seen a lot of actors draw conclusions from such data using pure...

## seeking scipy examples of swept-coefficient (time varying) filters

inI've been pleased with ease of use of the scipy.signal package for implementing bandpass filters: the `signal.butterworth()`,...

I've been pleased with ease of use of the scipy.signal package for implementing bandpass filters: the `signal.butterworth()`, `signal.sosfilt_zi()` and `signal.sosfilt()` functions do just what I expect for a filter with constant center frequency and bandwidth. But now I'd like to make the frequency and bandwidth settings be time varying functions themselves, and I'm not sure how to

## looking for early TI DSP evaluation kits

I'd like to find examples of early TI DSP evaluation kits like the TMDS3200026 for the Computer History Museum collection. Anyone have any...

I'd like to find examples of early TI DSP evaluation kits like the TMDS3200026 for the Computer History Museum collection. Anyone have any kicking around?

## Dolph-Chebyshev Window (octave+maxima)

inI have followed rick lyons article on this ,and using the example values he gives, the output matches. But using different parameters the...

I have followed rick lyons article on this ,and using the example values he gives, the output matches. But using different parameters the filter kenel ends up strangely wiggly. I must be doing something wrong. Here is what i've tried: in maxima: > N:32; > gamma:48/20; > M:N+1; > alpha:cosh(acosh(10^gamma)/N); > A(m):=abs(alpha*cos(%pi

### Ask a Question to the DSPRelated community

To **significantly** increase your chances of receiving answers, please make sure to:

- Use a meaningful title
- Express your question clearly and well
- Do not use this forum to promote your product, service or business
- Write in clear, grammatical, correctly-spelled language
- Do not post content that violates a copyright