Questions tagged [sound]
The sound tag has no usage guidance.
274
questions
3
votes
1
answer
1k
views
How to make pop-free, crisp two-beep ringtone?
I hope this ultra-noob question is not entirely out of place here.
I'm trying to make a super simple ringtone: 0.5s silence + 1s "pure tone" + 0.5s silence + 1s "pure tone" + 0.5s silence. By "pure ...
- 133
1
vote
1
answer
2k
views
What is the DTW result (applied to the MFCCs of an audio file) proportional to?
I have computed the MFCCs for two audio files and applied the DTW to both sets of coeficients for both files. Now each such pair the two files is described by one single value (computed by the DTW). ...
- 175
1
vote
0
answers
85
views
Length of frames for calculating cepstral coefficients
For audio classification we are using the cepstral coefficients and their derivatives. Which I calculate using the Matlab libary voicebox.
I am looking for some literature for how to choose the frame ...
- 333
1
vote
0
answers
622
views
How to convert a sound file to any other data format which can be manipulated
I know this is very basic question and i am new to this site. But can anybody help me with my question. How to convert a sound file to other data format say using some type of transform (FFT or DFT) ...
- 111
4
votes
1
answer
3k
views
How to decide the number of cepstral coefficients?
For audio classification we are using cepstral coefficients, but how should I decide the number of coefficients?
- 333
3
votes
1
answer
961
views
Ultrasonic data transfer
I am trying to send a short amount of data (10-15 characters) from one mobile device to another via (inaudible) sound within 1-2 seconds. I'd like to be able to deal with normal external noises (...
- 131
0
votes
0
answers
2k
views
Getting sound pressure level (SPL) for a frequency band from Welch's derived PSD
I'm using Welch's method (pwelch, in octave) to get the PSD of a recorded sound signal (i.e. pressure level vs. time). I then took the PSD data and took the sum of the amplitude in each octave band (1/...
- 1
9
votes
2
answers
6k
views
PC-to-PC data communication over Sound FSK / PSK / DSSS
For fun and work I've to implement a java based application that can Encode text or data to sound and transmit using PC's speaker and on the receiving side is a microphone with decoder software.
I ...
- 191
0
votes
1
answer
968
views
Calculating the gain for adjusting sound level to X db
I have a sound signal, and I would like to implement a simple realtime level control (for info, I am using Pure Data, but I'd like to know about the general case).
For this I thought of using the ...
- 283
0
votes
1
answer
1k
views
Generate buzzer sound
I'm trying to generate a buzzer sound like this one in matlab.
When you look at the waveform, it's got sinusoidal notches cut into an otherwise normal looking sinewave.
I generate a sinewave tone,
...
- 935
1
vote
1
answer
531
views
Sinusoidal Synthesis of audio
I am working on a sinusoidal encoder & decoder to compress .wav files. For now I am trying to regenerate the audio by combining all the frequencies of the original .wav file.
Here is the code I ...
- 111
8
votes
3
answers
8k
views
How is a human whistle a pure sine wave?
According to Wikipedia human whistling is a pure sine wave.
If that is true and if a human is whistling and produces a rhythm like any song, is he still producing a pure sine wave?
For example, if I ...
- 2,145
1
vote
1
answer
531
views
How to perform sound synthesis?
I am generating a simple musical instrument using a ST board. basically I have a sensor which detects motion or spatial angle and generates sounds of differnt pitch and volume depending on the angle. ...
- 155
1
vote
1
answer
681
views
Recorded an audio file using microphone via Windows Sound recorder, but has 2 channels that are slightly different. Why are they different?
I recorded sounds using a plug in microphone on a Windows 7 laptop. I used the Windows Sound recorder to record the sounds. It was only one microphone, but when I load the sound file into Audacity, it ...
- 113
0
votes
1
answer
497
views
How to amplify sound wave
I'm developing a singing game and I want to output player's voice through speakers. I'm using portaudio for that, I acquire the input signal and just write it to the output buffer. The problem is the ...
- 223
3
votes
1
answer
871
views
What features describe audio signals? (Besides frequency and amplitude)
I recorded sounds with a microphone and I try to distinguish them in my Java program. The frequency works quite good, but if I look at the fourier transforms it seems like there should be more ...
- 133
6
votes
3
answers
4k
views
How to de-noise raw sound data
What techniques/algorithms can I use to remove noise from a raw recording of sound (voice)?
The purpose is to get a smoother graph (removing the "jaggedness"). What I have tried was to average-out ...
- 163
8
votes
2
answers
8k
views
Loudness of PCM stream
I'm receiving PCM samples through stream which is one channel, 8000 samples per second. I figured out way of finding out loudness by calculating 'force' of signal by adding abs value of every next ...
- 211
9
votes
5
answers
3k
views
Why Do I Get This Crackling Noise on Zeroing out the High Frequencies?
I recently started playing with the Fourier transform (after spending a few weeks learning about the mathematics behind it). I decided to try hacking together a low-pass filter on the following sound ...
- 195
0
votes
4
answers
2k
views
Can FFT be used to find peaks and pits on audio files
I'm able to read wav files and its values. I need to find peaks and pits positions and their values.
First time, I tried to smooth it by $\frac{(i-1 + i + i + 1)}{3} $
formula, then searching on ...
- 11
1
vote
1
answer
348
views
Tool for Harmonic Analysis & Synthesis [closed]
I've been using a program for identifying harmonics for a wave after doing a fourier analysis.
http://www.phon.ucl.ac.uk/resource/sfs/esynth.htm
I would like to be able to tweak some of the ...
- 143
13
votes
2
answers
1k
views
Sound synthesis effects for natural sounds
I´m currently working on an accordion synthesizer and I would like to make it sound as natural as possible.
I really like how the following wave sounds:
https://dl.dropbox.com/u/20437903/onda%...
- 143
5
votes
3
answers
12k
views
Is there any free software that can recognize and classify sounds?
i am making a smart home automation software and i would like to know if there is any software that can recognize noises such as speech ,playing music,phone ringing etc
The exact software i am looking ...
- 153
3
votes
2
answers
37k
views
Maximum frequency of any mobile phone speaker
Which is the maximum frequency of a speaker of any common mobile phone? I would like to use sound to repel some animals, so I need playback sampling rate to be above 44100 Hz.
