FFT Question

Started by Tom Killwhang in comp.dsp11 months ago 7 replies

Why is it that in older textbooks the DFT or FFT is defined as having scaling of (1/N) for direct FFT whereas in newer ones it doesn't? If we take...

Why is it that in older textbooks the DFT or FFT is defined as having scaling of (1/N) for direct FFT whereas in newer ones it doesn't? If we take the DFT of say 1,1,1,1 the answer is 4 but surely an answer of 1 makes more sense as it is the average value. of 4 ones. I know people say - "Oh we can scale it later", but it doesn't make mathematical sense. The other point is that the


FIR filter design

Started by Tom Killwhang in comp.dsp11 months ago 2 replies

I am trying a simple example using frequency sampling. Therefore I have N=16 weights. W=[w0 w1.....w15] and I make then as follows W=[1 1 1 1...

I am trying a simple example using frequency sampling. Therefore I have N=16 weights. W=[w0 w1.....w15] and I make then as follows W=[1 1 1 1 1 0 0 0 0 0 0 0 1 1 1 1 ] as magnitude and the phase is -k*pi*(n-1)/N where k is from 0 to N/2 giving a frequency sampling complex vector of H=[h0 h1 h2 ....h15] Now according to textbooks I have to have conjugate symmetry but exactly how does t...


CFP: Special Issue JCR Q2 Entropy journal (IF:2.419). "Artificial Intelligence and Complexity in Art, Music, Games and Design"

Started by EvoMUSART in comp.dsp11 months ago

Journal: Entropy (ISSN 1099-4300), section "Complexity". JCR Journal with Impact factor: 2.419 (Q2). Deadline for manuscript submissions: 30...

Journal: Entropy (ISSN 1099-4300), section "Complexity". JCR Journal with Impact factor: 2.419 (Q2). Deadline for manuscript submissions: 30 September 2020. URL:https://www.mdpi.com/journal/entropy/special_issues/ai_complexity Flyer: https://www.mdpi.com/journal/entropy/special_issue_flyer_pdf/ai_comp= lexity/web Dear colleagues, A major=E2=80=94potentially unachievable=E2=80=94challeng...


Is fixed point arithmetic important anymore

Started by Anonymous in comp.dsp11 months ago 5 replies

DO many people still do DSP in fixed point or are the processors mostly floating point and the DSP designer no longer needs to work in fixed point?

DO many people still do DSP in fixed point or are the processors mostly floating point and the DSP designer no longer needs to work in fixed point?


Fourier Series

Started by Tom Killwhang in comp.dsp11 months ago 4 replies

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...

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?

Started by Piotr Mancini in comp.dsp1 year ago 8 replies

I 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?

Started by MatthewA in comp.dsp1 year ago 7 replies

Forgive 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

Started by rich...@gmail.com in comp.dsp1 year ago 4 replies

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...

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?

Started by Richard (Rick) Lyons in comp.dsp1 year ago 2 replies

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...

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

Started by Anonymous in comp.dsp1 year ago

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


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