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-1
votes
0answers
9 views

Segment audio signals + calculate the variances

I don't know any thing about Matlab, but I need to use it to analyze data as a part of my current project. So, could you please help me to figure how to do the following ? First, I need to segment ...
0
votes
1answer
31 views

Tutorial for a stereo Phaser in C++?

I was searching for a tutorial on how to implement a stereo Phaser in C++. All i´ve found was sourcecode with little or no explanations which did´nt help me much. Does anyone know a Tutorial with ...
0
votes
1answer
37 views

How to convert a recorded signal into sound or audio

I'm a undergrad student who doesn't have much knowledge in signal processing or programming. We're building an electrical stethoscope and to test this device we recorded the signal received from the ...
1
vote
1answer
96 views

Find similarity of sound signal

So I was working on a program to comparing the similarity between the pronunciation of a word, First I got the audio file, and I use FFT on it to get the amplitude over frequency array, then I just ...
-1
votes
5answers
127 views

Call recognition using Digital Signal Processing

We are looking for writing applications which would recognize Bird calls and Frog calls using Sound processing. EDIT: I want to identify the species of bird / frog and do not want to differentiate ...
-1
votes
1answer
23 views

what are the data that I can get from an Anechoic chamber

I have a bunch of piezo elements, that I want to use as "Mics" , for that I will test their reaction in a Anechoic chamber , my question is what the are characteristics that I can measure that ...
0
votes
0answers
31 views

How to add bandpass filter to recorded sound in matlab

I have a sound that is being recorded but I am trying to apply bandpass filtering to the sound so that it filters out anything above and below a selected frequency range. I have tried the tool in ...
0
votes
1answer
18 views

how to choose a mic and make sure not to overcahrge it

I'm not sure that's the right forum to ask this question but I'll do it anyway . in my project, I've to listen to different machines using an MEMS mic by fixing the mic directly on the machine , the ...
0
votes
0answers
33 views

Detecting white noise signal and narrowing the frequency in matlab

I created a white noise that is played in 2 channels. While the left channel is active the right is silent and vice versa. I am trying to detect the signal arrival time after it has run through the ...
0
votes
1answer
44 views

Segmenting a sound file before each of its attacks

Like the title says... I want to split audio file where a single instrument is played (not so fast)... I just need to detect the attack phase of the waveform to know where a played note begins. Can ...
1
vote
0answers
55 views

GCC-PHAT cross correlation

I am trying to implement GCC-PHAT in python. The approach is similar to the following two links: link1 and link2 It seems the only difference between GCC-PHAT and normal cross-correlation using FFT ...
1
vote
1answer
45 views

Air-coupled microphone

Does anyone know what the heck is a coupled-air microphone? I know that they were used for recording internal body sounds in papers like this and this. I googled the term, but I couldn't find any ...
1
vote
1answer
46 views

matching the mouth shape of an audio file(lip sync)

I am working on something like cartoon, but the character's mouth shape is automatically detected and matched by the word they are saying. my guess is to use speech recognize algorithm to analyze ...
0
votes
1answer
32 views

Inter aural time difference generation using sine waves

I have a stereo sound for Inter aural time difference consisting of sine wave(16 samples as 16 bit PCM Data) for left and right audio. From time to time I would like to advance either the left or ...
1
vote
5answers
175 views

Pitch Detection: avoiding frequency doubling / halving

I am working on a tuning app. I have so far tried 3 different libraries with a number of different algorithms. However, when I compare to other tuner apps, I seem to be getting frequency doubling on ...
0
votes
0answers
34 views

Less Fidelity Than HRTF

Is there a known or accepted simple reference model of the receiver pattern for a typical human listener? I am aware of the existence of the Head Related Transfer Function, and that is emphatically ...
1
vote
2answers
77 views

Recognizing bodily noises (ie, not spoken words)

I was pointed here by a chain of stackoverflow posts. I'm a software developer looking to make a module that recognizes noises like snorts and coughs. Here was my original question on stackoverflow ...
1
vote
0answers
42 views

How to synchronise two audio files using a marker

I'm working on a project on which we use WebRTC and the RecordRTC library to record audio files. I would like to be able to process the audio files server-side to ensure a good synchronisation. To ...
1
vote
1answer
36 views

How can I connect multiple microphones to my computer (more than 4) and process the outputs independently? [closed]

I am trying to create something like a heat map for sounds originating in a classroom to study the discussions inside the classroom. For this I am instaling directional microphones in various parts of ...
1
vote
1answer
330 views

Feature extraction for sound classification

I'm trying to extract features from a sound file and classify the sound as belonging to a particular category (eg : dog bark, vehicle engine e.t.c). I'd like some clarity on the following things : 1) ...
17
votes
4answers
1k views

What are the audio equivalents of images like “Lena”, “Mandrill”, and “Cameraman”?

I don't know what to call these images, but they're very often used in the image processing world as standard examples to show the output of a particular operation. Here's a link to the page ...
-1
votes
1answer
87 views

how to read full input signal with STFT in matlab

Please help! I am trying to figure out why in the code i have below my input signal is being cropped but in the code I have a full signal created. The white noise created is 5000 samples for the right ...
1
vote
1answer
55 views

What does it mean for audio to be 'sped up'? How can I undo it?

I very simply have a .wav audio file, but there is a note with it that says "This audio has been sped up by 10x". I am wondering, what does it mean exactly from a signal processing perspective for an ...
0
votes
1answer
480 views

how to apply Short-time fourier transform to code in matlab

Please Help, I have a white noise signal that I created and need help to apply the Short-time fourier transform to my code so that it can do the bandpass filtering. I am trying to put it in the code ...
0
votes
2answers
189 views

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: ...
0
votes
1answer
62 views

How to Concatenate white noise signal and applying bandpass filter matlab

I created a white noise signal. I am trying to use the array I have created with the white noise to play in 2 channels. When the left channel I was trying to have 5000 samples and the right will have ...
1
vote
1answer
42 views

Time-varying waveform

My situation is as follows: i am trying to generate a waveform the hard way, by constructing the samples one by one and then saving the result to a .wav file using Python. When the frequency is ...
0
votes
1answer
36 views

How to store the signal in a variable and plot the signal in MATLAB

I am trying to store the signal I have created in a single variable and graph the signal in two subplots in one single graph, one for left channel, one for right channel. ...
0
votes
1answer
58 views

How to add repeated beeps to sound created with a pause in between each beep in MATLAB

I have 2 sounds that I created and trying to make them beeps. Maybe 4 or 5 repeated beeps but have a pause in between each beep but make it still part of the signal. I think I have it so that the ...
0
votes
1answer
105 views

Creating 2D array to play audio in left and right channel in matlab

I'm new to matlab sound processing and I am trying to create a 2D array for the sound code below. I have to make the sound have 400 samples(i.e 10ms) at 20hz, but having trouble getting the code to ...
0
votes
1answer
112 views

Resonant peak frequencies for phaser effect

I have a conventional phaser setup with allpass filters and feedback. I can calculate the peaks frequencies of the phaser when the allpass delays are set to 1 (then they work as simple one sample ...
0
votes
2answers
75 views

Separating excitation from filtering for sound sythesis

From my days at college I rememeber that LPC splits a signal into a series of slowly changing filter coefficents and an audio-rate residual error signal, such that the original signal gets reproduced ...
0
votes
3answers
92 views

How to delay a signal by D degrees

I read in a paper that a sound signal can be delayed by D degrees. How can such a thing be possible? Isn't sound signals expressed only in terms of the time axis? Thanks in advance
0
votes
1answer
35 views

what is standard acoustic volume

In Audio Experts book, it's given as Sound pressure meters must be calibrated at factory to a standard acoustic volume. So what doth this ...
0
votes
1answer
294 views

Time-frequency representation of sound signal using Matlab

I am currently doing a project on sound signal processing by using MATLAB. I have a problem regarding creating the command line so that I can get a graph containing frequency by its time. But this ...
0
votes
0answers
70 views

AMARI ERROR in Matlab ( FASTICA Comparison)

I am now doing a project comparing non-linearities in FASTICA and the best way to compare them is by using AMARI error. Could I ask how to perform Amari Error after fastICA in Matlab?I tried to search ...
0
votes
0answers
16 views

Doubt A weighting curve's phon value

Some sources say A weighting curve is inverted from 40 dBSPL, i.e 40 phon, while some sources say it's inverted from 30 dBSPL. Which is true? PS: For example, this says 40 and this says 30 Someone ...
1
vote
1answer
122 views

Fourier Transform for frequency analysis

I applied Fourier transform on a sound (PCM generated digitally with sin function) and frequency detection is accurate. However, if I play the sound and record it, and then apply a Fourier transform ...
0
votes
1answer
59 views

Q value for a high pass filter

How to calculate the Q value for a high pass filter ? Ps: I'm a beginner in signal processing, so please put it in simple terms.
0
votes
1answer
38 views

Frequency filtering - Audio

Sound are digitalized in computers as an archive with its intensity amplitude at the given time. I want to ask a very simple question about frequency filtering. How it's done, if there's no frequency ...
2
votes
2answers
125 views

Need help with FFT results

I am playing around with FFT and cant seem to get the expected results. I have a sound clip that i recorded from a mic placed on an analogue clock. So it has a sound every second. ...
1
vote
1answer
106 views

Colored noises: Stationary or non-stationary?

I know for sure that white noise is considered as a stationary sound, but is that true for the rest of them? http://en.wikipedia.org/wiki/Colors_of_noise Also, can we meet some of these sounds in ...
1
vote
1answer
78 views

Pitch class profiling

Currently, I am developing a piece of software for chord recognition. There are FFT and pitch class profiling on it. I tried using the pitch class profile proposed by Takuya Fujishima, but the result ...
0
votes
2answers
100 views

Why do we follow Shannon's Theorem in audio sampling?

My professor told me that in sampling a signal, is not usual to respect the Shannon theorem because the interpolation formula contains sines and fractions which are difficult to calculate with a ...
-2
votes
1answer
78 views
1
vote
1answer
2k views

Separating two sound file frequencies using bandpass filter matlab

can someone please help me? I have a project to implement a superheterodyne transmitter and receiver without using matlab functions that modulate. The first part which I can't seem to get right is the ...
1
vote
1answer
179 views

How to compare 2 matrices of MFCCs, keeping the time information

I have a corpus of several thousand sounds. Now I pick a sound sample S, and I want to find in my corpus the sound S' that is the most similar to S. The application is for music, for a composition ...
0
votes
1answer
90 views

How to decipher this Microphone sensitivity Chart for Choosing a SPL meter

I have a mic having sensitivity chart as below which has relative dB on y-axis showing 1V/0.1Pa what does this convey how to read my mic's sensitivity a document on microphone sensitivity from ...
1
vote
1answer
84 views

Speech Enhancement Libraries

Is there any speech enhancement algorithm library? I need to process a sound to voice recognition, and I want to remove noise from audio source.
1
vote
1answer
137 views

Easiest Beat Tracking Algorithim

I want a relatively easy to implement but relatively reliable algorithm for detecting beat locations in an audio file.What I am aiming to do is get the location of the closest beat to a particular ...