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Questions tagged [windowing]

In signal processing windowing allows to work on overlapping segments of the signal.

224 questions
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Writing a simple Discrete Fourier Transform for real inputs in C

So I'm trying to write the Discrete Fourier Transform in C to work with real 32-bit float wav files. It reads in 2 frames at a time (one for each channel, but for my purposes I'm assuming they are both the same and so I use frame[0]). This code is…
maniciam
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R - Faster Way to Calculate Rolling Statistics Over a Variable Interval

I'm curious if anyone out there can come up with a (faster) way to calculate rolling statistics (rolling mean, median, percentiles, etc.) over a variable interval of time (windowing). That is, suppose one is given randomly timed observations (i.e.…
EconomiCurtis
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How to unit test a kafka stream application that uses session window

I am working with Kafka Stream 2.1 I am trying to write some test for a stream application that aggregates some events by their key (i.e by a correlation ID) using a session window with an inactivity gap of 300ms. Here is the aggregation…
gnos
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Use Kafka Streams for windowing data and processing each window at once

The purpose I want to achieve is to group by user some messages I receive from a Kafka topic and window them in order to aggregate the messages I receive in the (5 minutes) window. Then I'd like to collect all aggregates in each window in order to…
simo
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Mel Frequency Cepstral Coefficients (MFCC) in C/C++

Is there any implementation of MFCC available in C/C++? Any source codes or libraries? I've already found http://code.google.com/p/libmfcc/ which seem to be good.
Ali
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Is there any difference with the X11 atoms XA_WM_NAME and "_NET_WM_NAME"?

Is there any difference with the atom defined in XA_WM_NAME defined in Xatom.h and the one got using XInternAtom(display, "_NET_WM_NAME", False)? Edit: I made a little program which prints the integer value of both and I got: _NET_WM_NAME: 312,…
user301649
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Hopping vs Sliding Window

I understand tumbling window is set for an interval and the event's don't overlap and expires at the set time interval. Now both hopping and sliding windows overlap and in case of a hopping window we have a hop interval along with the normal window…
Vignesh I
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Delphi - overriding hide behaviour of TForm.showModal

I am currently writing a windowing system for an existing Delphi application. Currently, the program consists of a number of full-sized forms which are shown modally in the order they are required and none of which can be moved by the user. My aim…
jmc
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FFT - When to window?

I've seen the various FFT questions on here but I'm confused on part of the implementation. Instead of performing the FFT in real time, I want to do it offline. Lets say I have the raw data in float[] audio. The sampling rate is 44100 and so…
Skoder
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Xlib: How to check if a window is minimized or not?

How can I check if a window is minimized or not using the C interface of xlib? Edit: Should this code work? int window_is_minimized(Display *display, Window window) { Atom actual_type; int actual_format; unsigned long i, num_items,…
user301649
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how to close a window from a different process

I have a c# application which I want to instruct to shutdown nicely, from a different process. I also want to be able to ask it to open its main window. I have a reference to its main window handle. I know I can do it using elaborate schemes such as…
Aviad Rozenhek
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KISS FFT output with or without windowing

I am currently trying to implement fft into avr32 micro controllers for signal processing purposes using kiss fft. And having a strange problem with my output. Basically, I am passing ADC samples (testing with function generator) into fft (real…
Jin
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Count observations over rolling 30 day window

I need to create a variable that counts the number of observations that have occurred in the last 30 days for each id. For example, imagine an observation that occurs on 1/2/2021 (d / m / y) for the id "a". If this observation is the first between…
Amc
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Fast conditional overlapping windowing (framing) of numpy array

I have a huge list of numpy arrays (1 dimensional), which are time series for different events. Each point has a label, and I want to window the numpy arrays based on its label. The labels I have is 0, 1, and 2. Each window has a fixed size M. The…
Farhood ET
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How to use windowing functions efficiently to decide next N number of rows based on N number of previous values

Hi i have the following data. +----------+----+-------+-----------------------+ | date|item|avg_val|conditions | +----------+----+-------+-----------------------+ |01-10-2020| x| 10| 0| |02-10-2020| x| …
Smith
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