Questions tagged [algorithms]
Algorithm is a method expressed in a finite list of steps of well-defined instructions to process a signal.
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limiter algorithm wanted: mixing two channels without clipping
I have two audio tracks (instrumental recordings) named track A, and track B. The tracks will be played in an application and the user of this application has the ability to change the balance of ...
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Obtaining n values from n-1 sensors
As the questions states, lets consider we have 3 gas sensors giving me data for:
A
B
C
Note that only sensors for A and B give absolute values, yet we need the absolute values for all four species:...
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Which is faster: image segmentation or line detection?
Some papers use image segmentation techniques and others use edge detection. I need to know which one is faster.
update:
I need to do semantic segmentation for outdoor sense and the data is optical ...
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Removing known sequence from an audio sample
I have an audio recording of a conversation which is obscured by a movie playing on a television.
I have an audio recording of that same movie playing on that same television with no conversation in ...
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Can we use Tiva C series TM4C123GXL for signal processing experiment purposes? [closed]
I've newly bought texas instruments Tiva C series TM4C123GXL processing board for developing DSP application project. Is that processing board is good for that purpose? Is that well work with Matlab? ...
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Beginner's book in signal processing with practical examples on fault detection in electrical motors
I'm an electrical engineering graduate and I'm working on condition monitoring for electrical motors and generators. My goal is to improve reliability of electric rotary machines in such way, that any ...
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Is there a way to double all frequencies?
Let's imagine I have an input signal that looks like this:
$$
f(t)=\sin\Big(2\pi(2)t\Big)+\sin\Big(2\pi(3)t\Big)+\sin\Big(2\pi(5)t\Big)
$$
And I want an output signal that scales each frequency ...
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Why Is the Result of the Convolution of a Row and a Column a Two Dimensional Matrix?
I'm trying to understand a book chapter on "Algorithms For Efficient Computation of Convolution" (Also on Doc Droid or Scribd) and I know that when calculating the convolution of an image represented ...
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Control theory: how do you initialize input for a model predictive controller?
Although I think this is a pretty popular algorithm, I posted this question on electronics stacksexchange but received no response. I am posting it here to see if there are many signal/control experts ...
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Approximating $ {L}_{0} $ Norm Minimization with Non Linear Convex Inequality Constraints using Reweighted $ {L}_{1} $ Minimization
I have an optimization problem consisting of the $ {\ell}_{0} $ norm as the objective and a nonlinear (convex) constraint as well as a linear constraint. I am wondering if the reweighted $ {\ell}_{1} $...
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Which Transformation, Or Similarity Metric, Is Rotation, Shift and Scale Invariant?
I have an algorithm to to detect copy-move forgeries in images. I used block matching to detect regions of an image that were forged with copy-move forgery and highlighted the alleged areas. For block ...
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Efficient computation of Chirp Z Transform
Chirp Z Transform (1, 2, 3) is more powerful than zooming techniques (I use it to actually trace non-stationary chirp signals) and very usable in signal processing, but it's flexibility comes at price ...
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Phase invariant detection of low frequency spikes
I am a physics graduate student studying a new physical device via simulations. Thanks to SE DSP, reading Lyon's Understanding DSP as suggested (not all the way through it yet though), and a bunch of ...
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References on the MP3 encoding algorithm
Does anybody have a reference describing the MP3 algorithm in a step-by-step manner and clear to understand?
These references were a little bit confusing:
Audio compression using modified ...
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How does google automatically create 3D cityscapes?
In the last years, Google models not only are major cities, but also suburban and rural areas (google video)
I read that there are some tridimensional model building algorithm here.
How could such ...
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Bandwidth expansion by computing missing harmonics in music?
In old recordings or highly compressed audio files (lossy), the higher frequencies are lost, and we hear a distinctive muffling effect. (Just like if the song was played through a wall)
Is it ...
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Sample-By-Sample Linear Prediction
As I understand it and have it currently implemented, linear prediction [via Burg's method or the autocorrelation method] is a block algorithm. Hence, there will be latency involved because one must ...
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what are the Pros and Cons of ESPRIT and MUSIC algorythms?
On wikipedia there are only 2 lines about ESPRIT: Estimation of signal parameters via rotational invariant techniques (ESPRIT)... MUSIC doesnt have an entry in the music disambiguation page, other ...
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Is this graph of Wigner-Ville distribution OK?
I am studying some code for smoothed Wigner-Ville distribution.
update 3- solution, graph was over amplified in a 2d overdrive/oversaturation effect. if i divide by 20 only a line is visible.
Update ...
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Smoothing an LFO Sawtooth Wave
I'm trying to smooth a Sawtooth wave coming out of my LFO. Effectively the transition from 1.0 to -1.0 in a 1 sample step is causing clicks and pops if I modulate my audio signals amplitude with ...
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Calculating an exponential curve
I'm developing a synthesiser and have finished the LFO's. I'm wanting to provide a knob on the UI for setting the rate. The minimum value of the LFO will be .01 Hz and the maximum value will be ...
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How to get a Standard Deviation weighted average in image?
Now I'm trying to implement a SDLWGW algorithm by the MATLAB.
currently I'm referencing from Automatic White Balancing Using Luminance Component and Standard Deviation of RGB Components
The problem is ...
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Audio frequency modulation algorithm
I have a digital audio signal (float samples). I need to apply the Vibrato effect to a signal. "Vibrato" is no common term, but it is the same as the frequency modulation.
So, I need to ...
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How to Use the Walsh Hadamard Transform to Filter 24 bit RGB Color Values in a Localized Spatial Region?
After reading this Signal processing Stack Exchange article tonight, What Is the Walsh Hadamard Transform? How Could One Use It in Image Processing?, I became interested in applying the Walsh-Hadamard ...
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methods of computing fixed point atan2 on FPGA
I am in need of computing atan2(x,y) on an FPGA with a continuous input/output stream of data. I managed to implement it using unrolled, pipelined CORDIC kernels, ...
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Finding parameters of exponentially decaying sinusoids (Matrix Pencil Method)
The matrix pencil method is an algorithm which can be used to find the individual exponential decaying sinusoids' parameters (frequency, amplitude, decay factor and initial phase) in a signal ...
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Artificial Neural Network Preprocessing in Real-Time Applications
I've come across an issue with my ANN when attempting to port my offline analysis to an online, real-time, application.
I currently train my algorithm using an array of input data, number of ...
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Algorithm to effectively find perspective transform in motion estimation
I've shot a series of photographs in a sort of stop-motion fashion, and although the camera was mounted on a tripod, there are tiny motions between each two successive photos.
After some ...
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Algorithm to extract polygones with holes [closed]
I have this picture and would like to extract the bones.
First I thought of contour-Tracking, but as you can see in some bones there are holes (Like for example at the left finger, in the bone in the ...
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DSP for computer engineers
DSP is more kindred with electrical engineering than with computer science, how ever there are topics of DSP like MP3 encoding, JPEG compression and sound analysis can be understood by a computer ...
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Implementing a 1-D Kalman Filter Regression, Missing the smoothing action (getting the opposite)
I am implementing the 1D Kalman Filter in Python on a fundamentally noisy set of measurement data, and I should be observing a large amount of smoothing...but, instead, my Kalman Filter is doing the ...
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Pyramid vs Scale-space in Focus Stacking
I'm working on a focus stacking program, I wrote one a few years ago which used a very simple method, basically taking a DoG approach, but only operating on the single full resolution image. The ...
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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 ...
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buidling a bandpass filter without using inbuilt functions
I got an assignment which require building a bandpass filter without using any inbuilt functions. I wanted to create a third order Butterworth bandpass filter
...
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Voss algorithm and pink noise
the voss' algorithm generated a 1/f series. What does the series mean?
For example, we use three dice and the result sequence length is 8. Let's set the sequence is 8,15,6,9,14,10,9,7. Then what does ...
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Estimating the power consumption of an arbitrary, real-time DSP algorithm
Consider a digital signal processing algorithm that operates over a block of $L$ [samples], with a real-time constraint $\tau$ [s] (i.e. its throughput must be $L/\tau$ [samples/s]).
The theoretical ...
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Algorithm to identify periodic signal spikes
I'm working with a special chip that allows me to record current draw on phones. This chip logs data with its internal timestamps.
I now need to generate a unique signal that will allow me to map the ...
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What does "kernel based" mean?
In my thesis I try to explain what kernel based methods are, especially the meaning for object detection.
I know kernel based methods like Mean- and CamShift and I know how to use them. I understand ...
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How do I identify repeated subimages within a larger image?
I have a large image of a microscopic die of an integrated circuit. The pixel dimensions are something like 15000 x 10000.
Example image:
Commodore Amiga Paula Image http://tinytransistors.net/...
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HDR Imaging - Exposure Compensation
Tried HDR Algorithms of OpenCV. Since the algorithm takes pretty much time. I tried few alternative steps as follows.
Took sample images from: HDR Images
1. Divided the image into four equal regions ...
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Artificial Neural Network Example Problem
I was looking at an example of a NN but I dont understand in the Answer i where the .68 come from or .6637
This is the link of the tutorial
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Q matrix and updating times in a Kalman filter
The context of the problem is that I have several robots located remotely which give their position (x,y coordinates) every x seconds and send it to a centralized remote server. The value of the ...
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Looking for an arcsin algorithm
Does anyone have a simple algorithm for computing a reasonably accurate arcsine?
By "simple" I mean some sort of polynomial that requires <= 5 multiplications per output sample. And by &...
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4
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Algorithm for testing input sound for multiple expected notes?
** originally I asked this question on stack exchange and was pointed to dsp.stackexchange **
I need to determine when the correct musical notes (from a piano) such as in a chord are being played. ...
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0
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How to generate Gray codes of n bits that have at max k ones?
I understand Gray codes have one bit change between them and how to convert between binary and gray. But given a bit length of n, I want to generate a series of Gray codes (all possible) that have one ...
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Algorithm for detecting the time where the signal is above a threshold
I need to detect the time window where a 1D-signal is above a certain threshold. If it dips below the threshold briefly I'd like to merge the two windows, if it dips below for a longer time, split ...
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Difference between these two digital down conversion methods
I can think of two possible methods of digital down conversion. One seems superior to the the other for most cases, but I'd like to get some DSP experts' comments on the practical differences between ...
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Chromatography Baseline Placement
I have been looking around on Google, and I have not been able to find an explanation of how to do baseline placement in chromatography. what are some algorithms for placing a baseline on a ...
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What does "A Target with Zero Doppler" Mean?
I have seen several references to target at zero Doppler and some simulations that command users to place a target at zero Doppler. I know that when a target is flying tangential to the signal the ...
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Convex Optimization in Signal and Image Processing
In signal processing, convex optimization plays a useful role in problems such as sparse signal recovery and filter design. What other places does convex optimization appear?
For example, in ...