Questions tagged [preprocessing]
Preprocessing is a relative term that usually refers to simpler operations applied to improve the operation of a more complex algorithm.
55
questions
0
votes
1
answer
186
views
What's the purpose of augmenting an image with a random "gradient"?
I have the following Python code
...
user40095
0
votes
0
answers
165
views
FFT response for noisy signal, averaging the response and
I try to analyze a system's state with acceleration sensors by measuring the frequencies and amplitudes.
Since a cheap sensor is used, I have a noisy signal in the beginning (up to 40Hz - see below). ...
- 1
1
vote
0
answers
89
views
Measuring respiratory rate from a 3d accelerometer signal? How do I preprocess this data and move forward with it?
I have read a decent amount of papers that used wrist smartwatches to measure respiratory rate, or papers that used sensors attached to a persons chest. I can link them if it is necessary.
I am ...
- 11
0
votes
0
answers
57
views
Detect Trigger in vibrational data
I'm trying to classify states with a 1D-CNN-Network structure. Therefore I need to analyze the incoming vibrational data in a certain window. Two examples of such signals are shown below.
I'm ...
- 1
0
votes
1
answer
285
views
Help with automated baseline removal
This is more of a conceptual question, so apologies in advance if this is not the correct forum for such questions.
I am trying to find a repeatable and consistent method for removing the baseline of ...
0
votes
1
answer
159
views
How should I remove obvious anomalies from spectral data?
I'm working with raman spectra and it seems that our spectrometer produces some anomalies at very specific wave numbers and I'm looking to remove them from the dataset. Here's a picture of 27 spectra ...
- 33
-1
votes
1
answer
318
views
How to apply baseline methods to MNE preprocessed raw EEG signals?
I am new at EEG preprocessing and classification. I have followed Clemens Brunner's blog https://cbrnr.github.io/2018/01/29/removing-eog-ica/ as a tutorial for MNE.
This is how I have preprocessed ...
0
votes
0
answers
456
views
Upsampling and downsampling signals as a preprocessing step for a neural network
I have audio data acquired from a 4 channels sensors array.
As a preprocessing step for a neural network, I want to beamform and focus on the sound source. For higher resolution in the beamforming ...
- 682
0
votes
1
answer
935
views
How to take inverse fft of windowed and callibrated fft data? [closed]
I have done windowing and fft on a signal but when I try to recover original raw signal ,I am unable to do it .Can anybody help me.
How to take inverse fft of windowed and callibrated fft data?
...
9
votes
8
answers
4k
views
Is sound the best way to transmit a signal under water?
Could sound be used in transmitting sound waves under water digitally? Could the sound then be converted by a repeater to transit by radio waves? What other ways can a signal be transmitted other than ...
- 1
1
vote
1
answer
2k
views
Frequency analysis to determine low-pass cut off frequency
I collected some data for a practical application, where the signal represents force data obtained from an impact of a punch against a force plate attached to a quasi-rigid rig (it moves once the ...
0
votes
1
answer
2k
views
Subtracting DC Offset a Complex Signal?
If I take the magnitude of a complex signal, and then subtract the mean amplitude, I remove DC offset but lose the real and imaginary components. How can I properly subtract the DC offset of a complex ...
- 11
1
vote
2
answers
192
views
How do I know if my EEG signal need denoising?
I recently started working on sleep study.
For my research I download sleep EEG data from physionet. The EEG data has 100 Hz sampling rate and was recorded from 2 bipolar EEG site.
When I start the ...
- 143
1
vote
0
answers
163
views
Calculating gyroscope data from accelerometer and attitude data
I am currently collecting accelerometer and attitude data using smartphone sensors. Data is collected at 100Hz over 2.5 seconds. Of which there are 250 accelerometer points and 250 points representing ...
- 11
0
votes
1
answer
46
views
Does waveform-based ASR with lowpass filtering preprocessing still require the assumption of FFT?
I read some recent papers about time-domain speech recognition, and wondering if it steers away from the stationary assumption of FFT. However, some preprocessing operations like pre-emphasis and low-...
- 1