# Questions tagged [online-processing]

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### Clipping detection algorithm for a sinusoidal signal with noise and unknown amplitude in an online fashion

My problem is the following: I am sampling data from a sine signal Samples come in a online fashion (more and more data incoming through time). The device does not have a lot of memory so it is ...
• 11
59 views

### Online algorithm to detect non-directional volatility?

I'm trying to write an online algorithm to detect when a time series goes sideways (i.e., its mean trend or mean drift is approximately zero) but is also unusually volatile. For example, in the red ...
• 163
152 views

### Algorithm to detect down-up-down pattern in time series

I'm trying to write an online algorithm in Python to detect this below Down-Up-Down pattern in time-series. It's not hard to do roughly if I calculate 3 contiguous non-overlapping moving averages, and ...
• 163
50 views

### Questionable results of on-line butterworth bandpass filtering using scipy.signal.lfilter

I have a data_stream that I'm attempting to filter using two on-line butterworth bandpass filters to extract two frequency bands of interest. The original ...
1 vote
124 views

### Are there any recursive online max/min filters for time-series

Are there any online recursive filters that can approximate local, time-varying minimum and maximum values of a time series?
• 163
156 views

### Non Linear Recursive / Online Least Squares

I am searching for a recursive or online non linear least squares algorithm. I want to spread the computation out as new data is sampled like in the linear Recursive Least Squares or the LMS. ...
2k views

### Online DFT Algorithm

I have a discrete audio stream $x$ that needs to be processed in real-time. Specifically, as the each new sample is received, I would like to compute a Fourier transform of the last $n$ samples of the ...
• 185
71 views

### Optimize online weighted kurtosis algorithm

I am currently working on a Simulink block designed to perform an online computation of the weighted kurtosis typical of a certain signal. This block is part of a larger control algorithm, which will ...
• 627
683 views

### detect and distinguish driving maneuvers via smartphone sensors

I want to do some driving style analysis via smartphone. Therefore, I programmed an app that records a 2D acceleration (when accelerating/braking and turning left/right). The app calibrates itself in ...
• 131
16k views

### Filtering a digital signal online in real-time using python

I am currently trying to apply a bandpass filter to a signal in real-time. There are samples coming in with a constant sampling rate and i would like to calculate the corresponding bandpass filtered ...
• 197
484 views

### Web Online tools for feature detection methods in image processing

I'm doing a research about image processing, I would like to access common feature detection methods online, ex: Blob detection: Laplacian of Gaussian (LoG), Difference of Gaussians (DoG), ...
• 131