Questions tagged [java]
is a multiplatform computer programming language that is concurrent, class-based, object-oriented, and specifically designed to have as few implementation dependencies as possible.
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java resampling implementation using sinc function
To be as succinct as possible, I've written a Java method that implements resampling of a signal using the sinc function interpolation formula. When I test this code with a simple sinusoid, I'm able ...
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What do I measure in a Sound Sample Buffer to remove noise from an audio file using the Kalman Filter?
I am developing a computer program that removes or reduces the background noise from an audio file using the Simple Kalman Filter. I have implemented the Kalman Filter and a way of obtaining the "...
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How do I detune an audio sample by 1 hertz up or down from a copy of it
I have a program that can take a waveform, such as a sine wave or sawtooth wave and detune it with another waveform that is slightly sharper or flatter. It takes the frequency of said waveform and ...
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How do I add poles to this Biquad Filter for more rolloff
I now want a filter that has less of the frequencies to be cutoff. I would like a filter with 36, 48 or more decibels of rolloff
Code
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Use Fourier Transformation to compare 2 short audio files [duplicate]
I want to use Fourier Transformation to compute the similarity of 2 audios. I am dealing with small audios having the same size: 1 second length, mono channel.
My question is how can I use the Fourier ...
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How do I sort out my window sinc low pass filter
I started writing a windowed sinc low pass filter, but I cannot seam to get the code figured out right.
I followed these two links
http://doctord.webhop.net/Courses/textbooks/Smith_DSP/dsp_book_Ch16....
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Frequency modulation: which algorithm for discrete signals (Java, Swift, etc.)
I'm writing an audio app in Swift - and one task consists in frequency modulation of a given signal (microphone input or sound file) - thus I'm iterating through all frames of a buffer like
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Asymmetry In The Mirroring Of An FFT Of A Sinusoidal Signal
I am trying to implement a Cooley-Tukey FFT algorithm in its iterative version.
Specifically, I am implementing this Wikipedia pseudocode (please look at the section Data reordering, bit reversal, and ...
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Does this FFT algorithm give correct IFFT when the input does not contain symmetry?
This FFT function is from Numerical Recipies in C and I am using it in my java projects. The source code is given below:
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How to get coordinates(x(time),y(frequency)) of spectral peaks from spectrogram?
I have created this spectrogram from a wav file. Please have a look:
As it can be observed clearly that my somewhat spectral peaks are visible. I want to get the x = time, y= frequency of these ...
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resample interpolation decimation filters algorithm
I'm creating a program in order to perform Resample, Interpolation and Decimation Frequency.
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MFCC parameters for gunshot recognition
I'm writing a gunshot detector software. I'm using this article as reference:https://arxiv.org/ftp/arxiv/papers/1706/1706.08759.pdf.
For now, my software is able to recognize an impulsive sound. Now, ...
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Mirrored Spectrogram Mp3
First of all sorry if this is a stupid question, but I am an absolute beginner in this field and have been trying for days now.
I'm working on a java program that uses fft to analyze audio files.
To ...
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What is the proper way to implement a real time spectrogram?
I am trying to implement a real time spectrogram and I am not sure that I am implementing it the right way. First I decided to use Matlab, I was taking a short recording of lets say 0.1 seconds and ...
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issue in the mfcc function in java and matlab,not the same
I am working on a project for recognizing and identifying the sounds in real time(like baby crying, birds, door knocking...)by java, so I made a model by using audio files for 9 categories of sound by ...
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How to remove lines from captcha image which are acting as noise using java?
The images are attached here. I first converted the sample image to grayscale and then binarized it.
Finally i applied median filter to remove the dots from the image. However i am unable to remove ...
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low-frequency amplitude with phase modulation of low Hz carrier
I am writing an FM/PM synthesizer, using Java. For the most part it works pretty well. What I am curious about is an attempt to use a low frequency tone as a carrier. By low frequency, I mean in the ...
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How to smooth (or interpolate) phase of FFT and reduce data points
I am writing some code for audio analysis, and have currently got two signals with FFT performed on them.
I get the phase of my complex array by using:
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Problems with IFFT not being symmetrical
I have two signals, a measurement and a reference which I have performed an FFT on. They have both been windowed with a Hanning window, and now I would like to deconvolve these to get the impulse ...
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Cross Correlation in Java (Android) Using FFT (Frequency Domain Convolution / Correlation)
I want to implement cross-correlation with the start-symbol and the signal using FFT.
I zero-pad both signals to length N = x.len + y.len -1
Using the convolution theorem:
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Finding angles from an IMU (Quaternions to Eulers)
Greetings and apologies if this has already been answered, but I haven't been able to get a clear answer from looking on Stack Exchange so-far.
I have Quaternions coming from two different IMU's ...
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FIR filter - remove padded zeros
I am using this class to filter EKG data.
My sampling rate is 167/s and the length of data is 1670 (10 seconds), when I apply the filter I get the correct results but looks like the number of samples ...
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How to overlap two RAW audio signal
I hope I can find some help here.
I have started working on a little project concerning voice recordings. What I would like to is: given two audio files in RAW format (or WAV, as long as I can ...
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FFT and IFFT : filtering frequencies
I am sampling at $30 Hz$.
I have a sample of $N=150$.
Here is an example of how my sample looks like, which starts at 54 and ends on 203 on the X Axis
I am interested in observing frequencies ...
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Opencv Android Perspective Transformation not working as expected
I'm working with perspective transformation in opencv for android for a personal project.
The thing I'd like to do is to acquire a document like CamScanner does.
For this I import a picture and let ...
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Finding the fundamental frequency from Autocorrelated data
I'm writing an app in which I need to find the fundamental frequency of a note produced by a trombone. To do this I'm taking the FFT of audio data from a microphone and then using autocorrelation code ...
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How to perform an FFT on a signal with a sampling rate of 44100?
This is probably a very simple Signal Processing question but I can't quite work it out. I'm currently writing an android app which needs to perform an fft on audio data taken from the phone's ...
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Generating very short signals
So I need to program (using Java) some things that include generated sounds.
I am struggling to understand how to make it work because I require a rather short signal while still using a sampling rate ...
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Performing DFT of streaming audio problem. Is there a limit?
I am trying to write software that will perform the discrete fourier transform of real time data coming from the microphone into the sound card on a computer. I am using Java with the javax.sound APIs....
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How to Measure the Intensity / Saturation of a Color in an Image?
I have a task of developing an application to measure the intensity of a color in an image. I am researching about how to go about it.
Intensity refers to the purity of a hue. Intensity is also ...
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How can I implement image widowing in my image in Java?
My initial image is a medical image and my main objective is finding directionality. The original size of my image was 8X8 and I have rescaled the image to 32X32 to increase my accuracy. My input ...
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How can I increase image size by zero padding?
For increasing the image size from 8X8 to 32X32, I tried to do zero padding. The simplest concept of zero padding in Java for me seems to be the code as shown below in Java such that I can shift each ...
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Advice on autocorrelation via FFT
I have been creating an application in Java that transforms an audio signal and writes it to a midi file.
At first I tried using autocorrelation to find the fundamental frequency. However, I have ...
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FFT "Brick Wall" Low Pass Filter Not Smoothing Output
I'll try to be as brief as possible. I have very limited signal processing experience. I have a data set that consists of essentially a big old sine function (with deviations from ideality), and lots ...
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How to set sampling frequency of an acceleration data set
I have a set of accelerometer readings in $X, Y, Z$ axes obtained from an android based smart-phone. The data in $(X, Y, Z)$ was recorded at different time stamps and there is no uniform time period ...
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3D intensity map for grayscale image
I've got images of blood drops in grayscale and I want to generate 3D data where the first two dimensions represent the area of interest and the 3rd dimension represents the pixel intensity of that ...
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Compare two voices and outline their similarity
I am trying to develop an application which records the voice of someone through a microphone. I will have a preset recorded voices for the same words. I then need to compare the real time recorded ...
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How do I implement LIBSVM for multiclass classification using java?
I am currently working on an image classification project ,where i need to use bag of features model with libsvm(HIK kernel) for classification.I have extracted sift feature and created a visual ...
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How to implement anisotropic diffusion using java?
I am working on an image processing project in java where we use anisotropic diffusion for scale space generation.
In the below equation, after finding the diffusion value.using the second equation, ...
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Fixing my FFT Plot
I'm trying to plot my FFT of File. This i my result.
I made my FFT application:
I want to obtain something very similar to plot of WaveSpectra, please tell me my mistakes..
My FFT
The result from ...
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Upsampling PCM audio: from 6 kHz to 8kHz
What would a straight-forward way to convert an audio payload (PCM 16bit) from 6 kHz to 8kHz? I understand that this is an interpolation problem.
I fear that a linear interpolation would introduce ...
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Formulas to plot Frequency Impulse Response Coefficients
I made this question https://dsp.stackexchange.com/questions/19731/newbieplotting-fft-and-impulse-response-coefficients-using-java
I have the IRC: Impulse Response Coefficients:
$h(k), k = 0, 1,.., ...
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Is it necessary to apply some window method, to obtain the FFT? Java
I read that the window is needed to apply filter (Low Pass, High Pass, Band Pass or band Stop), but not for the FFT.
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What advantage does apply a window or disadvantage does not apply?
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What ...
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FFT calculation suitable, Wav File, Java
If I have a wav file with this characteristics:
16bits (2 Bytes per Sample)
32000 Sampling Rate
60 Seconds
2 Channels
then I have:
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Improving an auto-correlation based guitar pitch detector
I've seen many questions on this forum regarding pitch detection for musical instruments (commonly guitar), and spent a while reading through the answers to create a basic implementation of auto-...
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Android: fundamental frequency
I want to find the fundamental frequency for human voice in an Android Application. I want to use autocorrelation method. My code is this:
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Correlation Using FFT / IFFT (Convolution in Frequency Domain) in Java
I try to find about the delay between two audio files using Cross Correlation in Java. I've already done this algorithm so far that i get a idea about how many samples is the delay.
FFT x1 -> Zero ...
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Java amplitude processing
I have some code that collects amplitudes from a complex sound like a song. I now want to plot a graph of amplitude vs time, for the graph plotting I use JavaFX. However I get about 9 million ...
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possibilty of extracting a tone from MIDI values
I have a project of recording human's sound via Android's SoundRecoder API, and then displaying the extracted note on The screen. It is specific for Android platform (can't use Jmusic or Jfugue API as ...
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How to analyze audio input/spectrum correctly
I am quite new to Java and Signal Processing, but I was assigned a project dealing in audio processing. My topic given to me is a game that has a component of analyzing a song (any given song) and ...
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