Questions tagged [distortion]
The distortion tag has no usage guidance.
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Channel Estimate for OFDM shows distortion for first last order samples
The Channel Gain Estimation was obtained using Least Square method as follows:
Hk= mean(Rx_LTS ./ Tx_LTS, 2); k= -26 to 26
Where Rx_LTS is the received long training sequence (52 samples after ...
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What kind of distortion effect is this?
Here is the image of a plugin distortion I have applied to a sine wave.
The sound characteristic is heavily distorted and digital but still good sounding bass wave.
Any ideas what kind of distortion ...
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Stream gate - removing samples from timeline. Pitfalls?
I'm working with gnuradio. What I want achieve is extract signal from full stream by some kind of stream gate (based on tags) and after that write to file only timeline where signal exists. In my case ...
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Is this a noise or what? (Sinusoidal signal frozen for a short time)
I am studying a pair of AC signals for voltage and current. In a long run, I found a distortion happening as shown in the attached picture. I want to understand what could possibly have happened in ...
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Calculating THD vs. Frequency of an Acoustic System using the Exponential Swept Sine Method
I am working on analyzing the total harmonic distortion (THD) vs. frequency curve for an acoustic system. I am aware of the traditional method of exciting the system with a mono-frequency wave and ...
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DSP function used by musical distortion plugins
In short: what kind of mathematical function was applied to this sine WAVE?
I am trying to implement my own distortion plugins. Amongst other things I have read several chapters of Will Pirkle's book (...
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How to avoid harmonic distortions in a DAC?
I have a DAC which is assumed to be nonlinear, such that it produces unwanted harmonic distortions at integer multiples of the input frequencies. (EDIT: Any other nonlinear distortions, such as ...
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Troubleshooting distortion in room impulse response measurements:
I am collecting data for a project, where I am measuring the room impulse response by playing a sine sweep from a speaker (QSC K8 1KW Active Loudspeaker) and measuring it from the other side of the ...
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WAV file audio sync/distortion issue
I was using Scarlet 2i2 audio interface plugged into an Android phone. Monitor headphones on the interface sounded great! I recorded a WAV file of a kids' concert with the USB Audio Recorder Pro app, ...
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Strange Look to Sampled Sinusoid [duplicate]
Ok so as part of a project for school I have been designing an FIR bandpass filter. The output should have been a signal which looks like a sampled sinusoid but there was a strange alteration on the ...
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Nyquist frequency Plotting Distortions
I'm trying to plot some sinusoidal signals in Matlab.
But while frequency is getting higher (closing to fs/2), results are getting distorted.
I guess it's lack of my knowledge but distortion is ...
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Fixing distortion in photographic reproductions
I am currently building a photographic setup which I intend to use to make reproductions of a large amount of transparencies(positive and negative film strips). As I will be using a fairly small (1&...
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Advice on seperation of impulse responses for harmonic distortion orders
I am working based on Angelo Farinas paper: Simultaneous measurement of impulse response and
distortion with a swept-sine technique.
The purpose of the work is part of a loudspeaker measurement and ...
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387
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Group delay compensation for non coincident drivers
Suppose I have a two-way speakers system which can be modeled as a two-way Linkwitz-Riley crossovers network with impulse responses $h_{lp}(n)$ and $h_{hp}(n)$. I would like to equalize the group ...
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What happens when filter ringing is far longer than the signal itself?
I'm digging into some (quite popular in my field) analytical practice that I find suspicious. The problem is to remove the trend from some very short (eg. 18-40 data points representing 200 - 800 ms) ...
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Signs of waveshaping polynomial coefficients
I'm playing with some basic functions for distortion purposes. Odd order polynomials generate odd harmonics, even order polynomials generate even harmonics. When I combine them, both types occur at ...
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Deconvolution of signal with harmonic distortion
I came across these measurements done using a stepped sine sweep covering only some frequencies (~800 frequency points).
I would like to get an impulse response from these measurements to convolve ...
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Emulating tape distortion of low-level audio signals
I'm working on a tape echo emulation in Reaktor, and I've based the frequency response, tape speed warble, high-amplitude saturation and tape hiss on a paper I found about the Roland Space Echo. ...
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Error correcting code? - using RGB space with a lookup table
This problem could be thought about as how to transmit a signal with 3x8bit RGB in a way that is robust to the distortion of antialiasing blends colors.
The context: I need to rewrite a short utility ...
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High FIR order in time critical classification task
I have a question regarding filtering (bandpass in my case) as a preprocessing step before a classification task.
The frequency band I am interested in lies between 0.5 - 22 Hz which results in a ...
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Can harmonics be created or simulated a la carte
I am trying to learn about adding harmonics (audio) with a goal to make a plugin that can allow adjustment of the amplitude of each harmonic being added. I would not have the ability to write this but ...
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Fixing integer overflow in wave file
I have this recording from my DAW that showed a strange form of distortion: the signal clipped at many places, but instead of simply being clipped (loss of information), somehow the integer value of ...
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Finding the Transfer Function of a Multiplicative Distortion in MATLAB
I have the frequency response of two signals shown above. One is uncontaminated, and the other is the same signal contaminated by a multiplicative distortion with two poles and two zeros. I need to ...
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975
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How does image rotation affect the intrinsic camera parameters?
I am considering the problem of how to (manually) change camera model parameter to make it "valid" on a rotated image. This question tackles resizing, but does not consider lens distortion.
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340
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Exponential Swept Sine Distortion
I was able to get passable results on fundamental measurements using and exponential swept sine. Now I am trying to get distortion information from the same measurement but am puzzled by the results. ...
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Signal distortion under non-linear channel
The channel is given to have these characteristics, and its required to study the affect on Frequency Modulated signal and its demodulation.
Since there are no sharp corners (like during clipping) ...
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963
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What function to apply a Metamorphopsia (grid warp) translation?
How would I go about finding or creating a function to warp images dependent on grid lines surrounding an origin (I don't wish for a grid on my actual images):
It should work in practically the same ...
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153
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Understanding legacy code: Algorithm to remove radial lens distortion
The method below to remove lens distortion from a camera was written more than ten years ago and I am trying to understand how the approximation works.
...
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180
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Total Harmonic Distortion THD for the rectifier
I have a circuit with rectifier and this cause the non-linearity and consequently harmonic. I show it on the oscilloscope and then collect the signal from the oscilloscope to the computer by using the ...
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409
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Group Delay for Hilbert Transformer and Resulting Dispersion
An ideal Hilbert Transformer shifts the phase for all positive frequencies by $-\pi/2$ and all negative frequencies by $+\pi/2$ while maintaining constant magnitude everywhere. Group Delay is the ...
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How to quantify phase distortion of a filter specific to a signal?
For example, a EKG input signal is filtered with a known transfer function that does not have linear phase. How do you quantify the phase distortion of the output signal given you have the input? I ...
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How to prevent distortion after down-sampling?
I am new to audio signal processing, but in one of my machine learning projects that I am working on, I need to down-sample my audio somewhere in the middle of my neural network. Therefore, I need a ...
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How to measure SINAD of an audio signal?
I tried to measure the SINAD and SNR of a recorded audio signal using MATLAB. The following is the process I did to measure the 2 parameters:
Firstly, I generated an FM modulated signal(1 kHz audio ...
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240
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Distort voice to hide talker identity as much as possible
I need to develop an app which makes speech recognition. Because I need to be able to constantly improve the recognition capability, I would like to train the engine with real recordings and match the ...
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Recommendations for SINAD equipment
I am interested in buying a device that measures the SINAD of the audio signal(FM signal) that I receive from PC.
Here is the setup:
Signal generator (generating 1kHz FM signal ) $\rightarrow$ ...
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Any recommendations for buying SINAD measuring equipment? [duplicate]
I am interested in buying a device that measures the SINAD of the audio signal(FM signal) that I receive from PC. Here is the setup :
Signal generator -> attenuator ->HackRF connected to PC with SDR#
...
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Linear vs Non linear distortion
I'm learning about distortion and I got stuck at
"What is the difference between linear and non-linear distortion?"
(Also in frequency spectrum i.e. Amplitude and phase spectrum)
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Precise 5th and 7th harmonics of a sampled sine wave
Does anyone know in decibels (to 1/100th of a dB) what the theoretical 3rd, 5th and 7th harmonic of a 0dB fs 24-bit (i.e. full-level; 0dB = -8,388,607 to 8,388,607) sampled sine wave without dither ...
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Can I use SINAD for THD+N measurements? Are they inverse of each other?
I'm looking for a clarification, which I haven't really been able to find. It's probably obvious but I'd like to be absolutely sure of what I'm calculating.
I noticed that the formula that calculates ...
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Audio sounds oddly distorted [closed]
https://clips.twitch.tv/TangentialObliqueLobsterSaltBae
https://clips.twitch.tv/CharmingBashfulAlfalfaRickroll
https://clips.twitch.tv/NaiveKindGorillaGivePLZ
(Disclaimer: These were not recorded on ...
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Finding the memory polynomial model coefficients
I want to build a memory polynomial model given that I know the corresponding output signals for known input signals.
What is the easiest way to find the coefficients of it?
And how do we take the ...
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486
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Dithering adds harmonic distortion after filtering and upsampling
I have an issue which I wasn't able to solve for a few days. I have implemented a polyphase FIR interpolation filter within an FPGA which does interpolate by a factor of 8 or 16 times. I do accept an ...
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Why is distorted / quantized white noise still white noise?
White noise can be created by setting every sample in the time domain to a random number with a gaussian distribution. Every sample is random, so the frequency response is obviously random. Easy ...
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Identify the Type of Image Distortion (On Lena Image)
I want to understand the distortions in each of the lena images shown in the image below.
I see that the first one is a blur. How can undo the blur. The second one is colored salt and pepper noise. ...
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THD requirement for generated sine
I need to generate a sine signal using a DAC with a certain THD specification, say 0.1% @ 1KHz. As a first approach I’m considering it to be an ideal DAC along with an ideal LPF for aliasing removal ...
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Redistributing Color in a RGB Image According to a Gaussian Distribution
I haven't done this stuff in a while.
If I have an image $I$ I can equalize the histogram of the image using some opencv procedure, it's already defined. Equalizing an histogram means essentially to ...
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Can someone explain waveshaping to me?
Can someone explain waveshaping to me?
I only know it shapes waveshapes by passing through some functions, but I don't yet understand e.g. what the plots (such as the following in Melda Production ...
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Calculating Transfer Functions From Harmonic Distortion Percentage
Hi I am working on emulating a piece of analog audio equipment and would like to be able to create a transfer function based on the measured percentages of harmonic distortion.
I know that harmonic ...
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168
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Wave Shaper Function From A Waveshaped Singal
Is there a way to work out an unknown waveshaper function, that was used to distort and map the values of an input signal to new output signal, form the output if we only have input signal and the ...
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Norm MPEG-1 Layer III (Mp3) Filter banks distortion
So, I'm working with the filter banks used in Mp3, in Matlab. I am obtaining quite a huge distortion in the output and I don't really know whether I'm making something wrong.
I've reviewed the ...
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