Search found 6 matches

by dwilbourn
Mon Apr 25, 2022 9:34 am
Forum: SDL Discussion Forum
Topic: Concave hull
Replies: 0
Views: 2100

Concave hull

I see that you have a couple of routines for a Convex hull but is there any chance you might add similar routines for a Concave hull? I have been trying to implement one myself using the Moreira-Santos method (https://www.researchgate.net/publication/220868874_Concave_hull_A_k-nearest_neighbours_app...
by dwilbourn
Thu Mar 18, 2021 3:57 pm
Forum: SDL Discussion Forum
Topic: FFT for Highpass, Bandpass, Bandstop filtering
Replies: 2
Views: 6430

Re: FFT for Highpass, Bandpass, Bandstop filtering

Just to show I can sometimes make things work! :oops:

This link will download my expanded FFTFilter example program with Lowpass, Highpass, Bandpass & Bandstop modes.

https://we.tl/t-AZ4vsANK1A
fftfilter2.png
fftfilter2.png (32.57 KiB) Viewed 6428 times
by dwilbourn
Thu Mar 18, 2021 3:23 pm
Forum: SDL Discussion Forum
Topic: FFT for Highpass, Bandpass, Bandstop filtering
Replies: 2
Views: 6430

Re: FFT for Highpass, Bandpass, Bandstop filtering

I worked it out, I had not realized the significance of the comment: // set both positive and negative frequencies to zero in the example. You need to set both the 'high' and 'low' half of the spectrum to zero, then all the filters work exactly as expected. Unfortunately the low pass example appears...
by dwilbourn
Thu Mar 18, 2021 2:15 pm
Forum: SDL Discussion Forum
Topic: FFT for Highpass, Bandpass, Bandstop filtering
Replies: 2
Views: 6430

FFT for Highpass, Bandpass, Bandstop filtering

I have been looking at your FFT Filter example program, trying to work out how I can use the FFT for other types of filters, namely: Highpass, Bandpass & Bandstop. But so far I have failed completely! This is probably due to my limited grasp of how FFT really works. I have tried reading all sorts of...
by dwilbourn
Fri Nov 27, 2020 12:53 am
Forum: SDL Discussion Forum
Topic: TFeedbackProc
Replies: 2
Views: 6545

Re: TFeedbackProc

Thanks, I will give that a go!
by dwilbourn
Fri Nov 20, 2020 2:06 pm
Forum: SDL Discussion Forum
Topic: TFeedbackProc
Replies: 2
Views: 6545

TFeedbackProc

I would like to make use of the Feedback value in CountLinesInTextFile but I don't know how. The help just says "The type declaration TFeedbackProc defines a universal callback routine which is used in various mathematical procedures to provide feedback during time consuming calculations." Is there ...