Signal Processing Stack Exchange
Signal Processing Stack Exchange

Questions tagged [octave]

An octave is the interval between one musical pitch and another with half or double its frequency.

The octave relationship is a natural phenomenon that has been referred to as the "basic miracle of music", the use of which is "common in most musical systems". It may be derived from the harmonic series as the interval between the first and second harmonics. The octave has occasionally been referred to as a diapason.

Source: Octave

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Denoise Image with Gaussian Noise Using MATLAB / Octave

I want to remove a noise for an image using MATLAB, when the observed image is $$f=u+v$$ where $u$ is the restored image (is the image i want recovered) and $v$ is the gaussian noise. To restore $u$, I solve the following minimization…
Achaire
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Calculating 1/3 Octave Spectrum from FFT / DFT

I am not often on this forum and I am not an expert on the subject. I struggle with the theory of FFT / DFT and the 1/3 octave spectrum. Assume I have a DFT analysis of a given signal. It (the DFT analysis) consists of many equidistant frequency…
Dr. Manuel Kuehner
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Looking for a better algorithm for finding the slope of an input signal

I've got an input signal that while sloping up, approximately bounces off an imaginary line. I'm looking for the equation to that imaginary line. I have a method, but is very brute force and it takes too long. I'm looking for ways to optimize my…
Dale
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What is an octave? It is said to be eight, but I cannot see the eight anywhere

When I searched for octave, I listened to the fact that if you take an octave band the lower cutoff is double the upper cutoff. Where is this name octave coming from, that is, where does the figure eight show its significance in the above…
kakeh
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creating a seamless signal / loop using interpolation

I'm trying to create a seamless loop using a "non-periodic" signal using interpolation to smooth out the beginning and the end but I'm still getting a click at the beginning when it loops and I listen to it. Can interpolation do this? Please Note…
Rick T
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Why did my sine wave turn into a square wave when written to a WAV file in Octave?

I am trying to use Octave to generate a pure sine wave. The code for the same is as follows: x = 10.*sin(2*pi*(300/16000)*(0:1:400)); The sampling rate is 16000Hz, the sine wave is at 300 Hz. I write the above wave to a file using wavwrite like…
Sriram
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Impulse Response to Frequency Response in Octave

Having an impulse response of an audio system recorded as a wav file, how to calculate the frequency response of the system with octave?
sergej
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Verifying MFCC Final Result

I have created a Octave code for MFCC calculation for speech recognition, which takes a wav file as input and then gives the MFCC as the output. But the final results are a bit confusing, so I am unable to verify if they are correct or not. My…
Mohit
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Measuring frequency response range of piezoelectric disc

How can I measure the frequency response range of a piezoelectric disc below. I don't have an oscilloscope but I do know how to program in matlab / octave I was thinking of creating a swept signal in matlab and playing it through my laptop or…
Rick T
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Anti-aliased boolean masks for integration of CCD images

(This question was already asked on Stack Overflow under the tags Matlab/Octave/Signal-processing/Image-processing, but I am reposting it here following the advice of one user that this site may be a more appropriate forum for such questions.) Is it…
calvin tiger
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How to prevent Octave Jumping in ACF of Speech Signal?

I'm working with speech signals and my aim is to estimate the fundamental frequency $\ F_0$ of this signal often called as "pitch". The main idea is taking small blocks of the speech signal such that stationary can be assumed. Then calculating…
kubicwerke
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Compensate for phase shift of Hilbert transform

I'm using Octave and trying to use the "instfreq" function from the time frequency toolbox which requires an analytic signal input. To get this analytic signal I'm using the Octave function "hilbert" on my real valued signal thus: analytic_sig =…
babelproofreader
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Combining two wave generation formulas does not work as expected (MATLAB/OCTAVE)

I'm trying to convert sawtooth wave calculation formula to Octave/Matlab language. Here are the original formulas. My Desmos take is here. I've got formulas for triangle wave and square wave working but, sawtooth won't work in either way like showed…
Juha P
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Autocorrelation and Spectrum Density

Wiener–Khinchin theorem states that autocorrelation function and power spectral density are a Fourier-transform pair - see Wikipidia (and lots of other resources). That means autocorrelation should be able to be obtained by inverse Fourier transform…
sofname
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Frequency Response Error for IIR Butterworth in GNU Octave

I'm wondering why the following code for GNU Octave appears to be incorrect in the frequency domain by a magnitude of 2. For example, in Figure 1. (Sorry, I'm apparently not allowed to post images!) it can be seen that the -3dB points of the…
Brian Sidebotham
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