On 21 April 2012 01:30, <s...@sfxmachine.com> wrote: > This method is also discussed in Crochiere & Rabiner's Multirate Digital > Signal Processing book, but it didn't make sense to me there either - I'm > assuming this is my problem, not theirs. Apparently this method windows > the input with a window of size N = 4K, then intentionally time-aliases > the signal by stacking and adding it in blocks of K samples, then takes > the FFT of the time-aliased sequence. On the synthesis side, it takes the > inverse FFT, periodically extends the result, applies a synthesis window > and overlap adds. The periodic extension is the transpose of the windowing > and aliasing in the analysis process, which fixes everything somehow...?
So Crochiere's book discusses synthesis? Unfortunately I don't have it... In any case, simple periodic extension and windowing didn't work for me (it produces echo/flanging as one might expect)... > I'm afraid to try this, because it doesn't make any damn sense, and if it > works it might make my brain explode. When you get the courage try Richard Dobson's free VST plugins to hear that it works ;) > I'm curious what they're on about with this, but not quite curious enough > to try it, since it can't possibly work unless it does. :DD > Maybe it yields perfect reconstruction so long as you don't listen to the > output. lol :D > Anyway, I'm hoping someone will tell me it sounds great and makes > everything all better in the time, frequency, and efficiency domains. Well, to thank you for the great geek-laughs the least I can do is share that, so far, this technique does seem to make a positive difference ;) -- "What Huxley teaches is that in the age of advanced technology, spiritual devastation is more likely to come from an enemy with a smiling face than from one whose countenance exudes suspicion and hate." Neil Postman -- dupswapdrop -- the music-dsp mailing list and website: subscription info, FAQ, source code archive, list archive, book reviews, dsp links http://music.columbia.edu/cmc/music-dsp http://music.columbia.edu/mailman/listinfo/music-dsp
