lauwer@cs.hw.ac.uk (Jean-Marc de Lauwereyns) (05/07/90)
In the article <1990Apr21.223430.13206@IRO.UMontreal.CA>, Normand Williams wrote : > Hi, I am looking for Fast Fourier Transform written in C > that I could use for image processing. Is there a package on the net that > would include forward and inverse FFT, Spectrum calculation etc? I would > appreciate that you reply to me directly, Thank you. NW I have developped a 2-D Fast Fourier Transform for a project I have been working on (fractal landscapes), because generally, this kind of thing is given for 1-D but not for 2-D. So I have developped the algorithm for a 2-D array of doubles in C. If you want it I can send it to you directly, but I will not post it on the net for a good reason : people are charming when they want help and you are answering them on the net, BUT when it comes to be your turn to be helped, what a spectacular thing you see !!! nobody ever answers your messages, even if they are urgent, ..., especially when you are a student : you have not enough credit. So if you want this 2D FFT I can send it. I can also send you the pacal-like pseudo-code for the 1D FFT that I used as a skeleton to see how a FFT is working. Jean-Marc Jean-Marc de Lauwereyns | ____ | e-mail addresses : Heriot-Watt University | |\ /| | \ | JANET: lauwer@uk.ac.hw.cs Computer Science Department | | \/ | |___/ | ARPA.: lauwer@cs.hw.ac.uk Edinburgh | \___/ |___| \ |
dave@imax.com (Dave Martindale) (05/08/90)
In article <879@odin.cs.hw.ac.uk> lauwer@cs.hw.ac.uk (Jean-Marc de Lauwereyns) writes: > >If you want it I can send it to you directly, but >I will not post it on the net for a good reason : people are charming when >they want help and you are answering them on the net, BUT when it comes to be >your turn to be helped, what a spectacular thing you see !!! nobody ever >answers your messages, even if they are urgent, ..., especially when you are >a student : you have not enough credit. Oh, don't be ridiculous! Asking for help on Usenet is like walking into a university cafeteria, standing up on one of the tables, and shouting "I need help on <description of problem>". If your problem is personally interesting to someone who hears you, they'll help. If it's something they solved recently, they'll also probably help. If they think you are asking for help without having done enough homework yourself, they'll ignore you. If they are in the midst of a more interesting discussion with someone else, they'll ignore you. And you won't reach anyone who isn't in the room. In general, Usenet is an excellent resource for gathering other people's experiences with a piece of hardware, or an algorithm, or discussing a topic that is of current interest to readers. I've had quite good results asking such questions in the past. But any answers you get are purely voluntary - nobody here owes you anything! Just because a problem is important to you, don't automatically expect it to be important to anyone else. And if you give the impression that you *expect* someone to help you out, you're being rude - why should anyone bother to help you? In the particular case of your problem with "The Science of Fractal Images", 1. the original article never did reach here; possibly most of Usenet never saw it. 2. I, personally, don't have the book in question, so I don't have enough context to understand your questions about Fourier transforms - and you don't provide enough context for your questions without the book. Dave Martindale