A high-pass filter is a device that passes high frequencies and attenuates frequencies lower than its cutoff frequency.
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How do decide which order my butterworth filter should have?
I have a signal that was recorded with around 300 samples in a second. Now I want to run a low pass and a high pass butterworth filter over it. The frequency for the high pass filter is around 0.05 Hz ...
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Why is Prewitt filter High Pass
Prewitt filters are popular filters in image processing for edge detection
http://en.wikipedia.org/wiki/Prewitt_operator
Can anyone give a proof on why Perwitt and other edge detecting filters are ...
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LPF and HPF Confusion - Rectangular and Circular Cut-Offs
Interpreting some homework, I'm a little confused on what it's asking for. I'm asked to filter in the frequency domain (easy enough, just a fft2 and ifft2 when I'm done) a 256x256 8bit grayscale tiff ...
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Is it correct to subtract a low-pass filtered signal from the original signal and use the result as a “high-pass”?
I am having a hard time trying to find documentation to implement band-pass or high-pass filter with python/scipy/numpy.
I can easily create and apply a low-pass filter, though, so I ask:
Would it ...
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177 views
Filtering of streaming audio
Given something like 103 data points ($N=103$), a DFT will give back 103 frequency values. Then to do something like filtering the high frequencies involves setting the high frequency values from the ...
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complementary IIR filters
I would like a pair of complementary IIR filters (lowpass/highpass). By complementary, I mean, when the output from the two filters is summed, the original signal is recovered. I thought I could build ...
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Analyzing movement of fringes
I have taken a series of images of a fringe pattern at regular time intervals. This fringes are generated by shining a laser beam onto the CCD camera. The laser goes through a lot of optics, which is ...
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Normalizing Negative filter coefficients for Digital filter design
I am designing a High pass Digital filter. I calculated the filter coefficients using fdatool and got some negative filter values.
Now, I need to convert them into values from 0 to 255.
In case of ...
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What is the physical interpretation of Lowpass/Highpass filtering?
In Image/Signal processing context we have seen/we know that if there are say 4 samples and if we take an average of those 4 samples, then we say that the result sample is a low pass filtered output ...
