Without delving into to many details: I have spent the night preparing for my gig at the Enormous Room with Stefan Helmreich. Several years ago I made a highly crappy frequency shifter that went beyond the Nyquist limit, thus flipped. The idea was for a CD of mine, based on Ryoji Ikeda’s +/- so that I would have my remixes (private since not © cleared) but if you linearly flipped the frequency domain around 1/2 the Nyquist limit, which effectively turns the sound upside down so highs are low and lows are high—and by lows that include extremely lows (not that that is usually relevant) and the highs that are way above the threshold of hearing (say, between 16kHz and 20kHz—some MP3 algorithms even chop off at 16kHz, though not the good ones): I thought, well, I could stick Ryoji Ikeda’s originals in the very high non-audible range of the “audible” spectrum. I do things sometimes, like use a silly code or include tricks. I never do anything maliciously, unlike most people who use codes or who embed things steganographically. This was a tribute and an honesty.
The idea of it being a frequency shift rather than transposition was so the range of frequencies would remain the same. See, 10kHz to 20kHz is an octave, so is 440Hz to 880Hz (concert A4 to soprano A5). And I wanted it flipped. SPEAR is an excellent analysis program written by Michael Klingbeil; it has a flip feature, using the highest partial that remains after the McAuley Quatieri algorithm after the FFT inevitable strips some less useful frequencies, as the axis of symmetry. So I used MaxMSP’s [freqshift~] object—I am teaching MacMSP to my advanced class presently—and pushed it past the Nyquist limit so that the highest energy partials—normally the lowest frequencies—would be the highest, this most hidden and less likely to leak.
The frequency shift was simply the trick to flipping, due to the reflection of frequencies at 22.05kHz at the usual CD 44.1kHz sampling rate. I did so [biquad~] filtering of the hidden sound before it went up there, around 6kHz which is pretty pathetic. Then I chopped off some of the normal (“forward”?) sound (they for me are both forward, I’m boringly regular, though less so in some way that one might imagine). The hidden audio message was pretty ugly in sound quality, so I added a fairly naïve pitch transposition to push information downwards; thus within 6kHz for the to-be hidden message, I could, say, hold up to 12kHz of information if I transposed it down an octave. But that kind of compression loses half its information, and then some, due to mathematical noise. There are the same number of “slots” or FFT bins available for the data, no matter what you do with it except if you are very DSP-savvy, which I am not; now there is math getting it there, and math retrieving it. It is not symbolic, rather, number-crunched, hence rounding errors, ripple due to windows, etc.
That indeed is very noisy, especially on MaxMSP which doesn’t have good transposers. I sometimes put it through an [allpass~] filter to reverberate it, again naïvely so—but I didn’t care as it wasn’t a serious venture, just s silly something, actually, mainly to show my class—it by delaying certain phase-shifted frequencies. Kind of a cheat; plus I altered the signal and i/o vectors sizes, which made a huge difference. (I’ve left out many details here, for a reason; it has something to do with being mugged, and my ear being attuned to something, so I haven’t explained, say, how the filters tracked sounds, and all that; the MaxMSP patch was an application, meaning the patching information was hidden, so I couldn’t even see it, after the mugging when I lost everything, as in, everything. I’ve talked about that elsewhere. Plus I write very idiosyncratically, and despite what people think, the visual aspect is sui generis.) [I have been receiving the standard barrage of emails and texts. Probably Bacon’s first idol—associating things too readily. Anyway, when I get pissed off, I post more. They’ll teach me to swim one day, but, hee hee, I have a special skill in the swimming department! I’ll write this in my other bulletin too, I think. Really, truly, madly (actually, not), deeply, wisely, and see below about what this is really about—initials SP! ;)
I demonstrated this to my classes two-to-three years ago, part of my general practice of not keeping secrets when it came to secret things(! I’ll get the semantics correct one day), i.e., I suppose an insurance policy against being accused of hiding nefarious messages there JOKE, or being falsely identified with something JOKE. Just a stupid brag because I do feel somewhat stupid around some students at these fancy universities; rarely an event zapped. Without me feeling silly. But such zapping is harmless. I suppose. And I can assure you, I have never used it fo’ shizzle; on one piece—I shan’t elaborate, only to say I have written about it in connection to rape of all things—fairly irrelevant and I might be getting customs of other countries badly wrong here, so I take that back (epar), but that is my token to identify something—I stripped it before I gave it to the person who wanted that piece. [Re-reading, this is jumbled.]
It was not on the final version; perhaps it was on the mugged version—which was a copy of everything I have ever done—I did find back-up disks weeks later, but they replicated things on the Drobo 3.4TB system—I’ve explained the mysterious return of the cover of it, my SIM card, my laptop being returned but not my bag, and the laptop being scoured for 3 hours then after I used it a couple of times, it died. Etc. I’m kind of rushing writing this because I have the gig tonight and I am not prepared, but I think... therefore... I hate being under-prepared.
One other person was given the algorithm’s description in detail (I rambled it at a talk to No.6 club—a sort-of frat at MIT, 18 months ago—perhaps at Wellesley more recently, I forget), and I gave it to only one person. I shan’t say who that is, of course. Saying this ends friendships, and no-one has ever liked messiness regarding (especially) intellectual copyright (heck, this is exactly that, all these legal patheticnesses, what with my divorce almost two months ago, which in South Dakota means it is probably fully gone through—I am joking of course when I say that now we can testify against each other... JOKE I miss Katie NOT A JOKE a truly wonderful person—see, I said it boldly).
—or artistic. I’ve gone on about honesty elsewhere. If I were sensible I would probably write a poem about this in the style of Lewis Carroll. But a little more earnestly, since I couldn’t even dream of being as multitudinously clever as the Rev. Charles Lutwidge Dodgson. I just wrote about The Carpenter and the Walrus. Next on the agenda, The Owl and the Pussycat. I’m getting a kitty this week! I met a student’s black kitty, perhaps the softest, and friendliest/sweets little beastie I have ever met. And there is a teeny tiny fully grown black-tortie in my building! I saw her for the first time today, like a little loaf of purriness.
Anyway. I won’t elaborate. I need breakfast. Trident Bookstore’s huevos rancheros methinks. But I did find something very shocking, as if I am not reviled enough for all the shocking things I find. That is, self-reviled. That saddens me. And to be fair, I developed a new algorithm a few days ago, which I have been working on, and it is sweet. Noisy, but fabulous. It is an insurance policy on a different planet, as some would say, in the Galactic Federation. or Atlantis. Or GG Land, which is in the capital G of Greenland, like something else I’d like to point out in a future post, which is related to Algeria I think, and a park in New York. At least I can use all this craziness for my job—art stuff. Hence the relatively low salary, but “low” is not a complaint. It is a great job, and I just described why.
(I cache all interesting webpages and back them up on paranoid, oops, cautious servers. It isn’t paranoia, because I can’t experience fear. Hence Amfs’s name.) So I’ve had a busy night.
Clank clank clank whisper, this is MY SCREENPLAY!!! I will eventually write out some of the really early stuff from the green fake snakeskin book (It might have been a fake snake). I had promised not to write anymore, and just put up pictures and pieces of music, but this was kind of exceptional. It is the first time I am cross-posting a message too. Oh, and videos, like ones I will be showing tonight.
Check out my other blog for my name....
The idea of it being a frequency shift rather than transposition was so the range of frequencies would remain the same. See, 10kHz to 20kHz is an octave, so is 440Hz to 880Hz (concert A4 to soprano A5). And I wanted it flipped. SPEAR is an excellent analysis program written by Michael Klingbeil; it has a flip feature, using the highest partial that remains after the McAuley Quatieri algorithm after the FFT inevitable strips some less useful frequencies, as the axis of symmetry. So I used MaxMSP’s [freqshift~] object—I am teaching MacMSP to my advanced class presently—and pushed it past the Nyquist limit so that the highest energy partials—normally the lowest frequencies—would be the highest, this most hidden and less likely to leak.
The frequency shift was simply the trick to flipping, due to the reflection of frequencies at 22.05kHz at the usual CD 44.1kHz sampling rate. I did so [biquad~] filtering of the hidden sound before it went up there, around 6kHz which is pretty pathetic. Then I chopped off some of the normal (“forward”?) sound (they for me are both forward, I’m boringly regular, though less so in some way that one might imagine). The hidden audio message was pretty ugly in sound quality, so I added a fairly naïve pitch transposition to push information downwards; thus within 6kHz for the to-be hidden message, I could, say, hold up to 12kHz of information if I transposed it down an octave. But that kind of compression loses half its information, and then some, due to mathematical noise. There are the same number of “slots” or FFT bins available for the data, no matter what you do with it except if you are very DSP-savvy, which I am not; now there is math getting it there, and math retrieving it. It is not symbolic, rather, number-crunched, hence rounding errors, ripple due to windows, etc.
That indeed is very noisy, especially on MaxMSP which doesn’t have good transposers. I sometimes put it through an [allpass~] filter to reverberate it, again naïvely so—but I didn’t care as it wasn’t a serious venture, just s silly something, actually, mainly to show my class—it by delaying certain phase-shifted frequencies. Kind of a cheat; plus I altered the signal and i/o vectors sizes, which made a huge difference. (I’ve left out many details here, for a reason; it has something to do with being mugged, and my ear being attuned to something, so I haven’t explained, say, how the filters tracked sounds, and all that; the MaxMSP patch was an application, meaning the patching information was hidden, so I couldn’t even see it, after the mugging when I lost everything, as in, everything. I’ve talked about that elsewhere. Plus I write very idiosyncratically, and despite what people think, the visual aspect is sui generis.) [I have been receiving the standard barrage of emails and texts. Probably Bacon’s first idol—associating things too readily. Anyway, when I get pissed off, I post more. They’ll teach me to swim one day, but, hee hee, I have a special skill in the swimming department! I’ll write this in my other bulletin too, I think. Really, truly, madly (actually, not), deeply, wisely, and see below about what this is really about—initials SP! ;)
I demonstrated this to my classes two-to-three years ago, part of my general practice of not keeping secrets when it came to secret things(! I’ll get the semantics correct one day), i.e., I suppose an insurance policy against being accused of hiding nefarious messages there JOKE, or being falsely identified with something JOKE. Just a stupid brag because I do feel somewhat stupid around some students at these fancy universities; rarely an event zapped. Without me feeling silly. But such zapping is harmless. I suppose. And I can assure you, I have never used it fo’ shizzle; on one piece—I shan’t elaborate, only to say I have written about it in connection to rape of all things—fairly irrelevant and I might be getting customs of other countries badly wrong here, so I take that back (epar), but that is my token to identify something—I stripped it before I gave it to the person who wanted that piece. [Re-reading, this is jumbled.]
It was not on the final version; perhaps it was on the mugged version—which was a copy of everything I have ever done—I did find back-up disks weeks later, but they replicated things on the Drobo 3.4TB system—I’ve explained the mysterious return of the cover of it, my SIM card, my laptop being returned but not my bag, and the laptop being scoured for 3 hours then after I used it a couple of times, it died. Etc. I’m kind of rushing writing this because I have the gig tonight and I am not prepared, but I think... therefore... I hate being under-prepared.
One other person was given the algorithm’s description in detail (I rambled it at a talk to No.6 club—a sort-of frat at MIT, 18 months ago—perhaps at Wellesley more recently, I forget), and I gave it to only one person. I shan’t say who that is, of course. Saying this ends friendships, and no-one has ever liked messiness regarding (especially) intellectual copyright (heck, this is exactly that, all these legal patheticnesses, what with my divorce almost two months ago, which in South Dakota means it is probably fully gone through—I am joking of course when I say that now we can testify against each other... JOKE I miss Katie NOT A JOKE a truly wonderful person—see, I said it boldly).
—or artistic. I’ve gone on about honesty elsewhere. If I were sensible I would probably write a poem about this in the style of Lewis Carroll. But a little more earnestly, since I couldn’t even dream of being as multitudinously clever as the Rev. Charles Lutwidge Dodgson. I just wrote about The Carpenter and the Walrus. Next on the agenda, The Owl and the Pussycat. I’m getting a kitty this week! I met a student’s black kitty, perhaps the softest, and friendliest/sweets little beastie I have ever met. And there is a teeny tiny fully grown black-tortie in my building! I saw her for the first time today, like a little loaf of purriness.
Anyway. I won’t elaborate. I need breakfast. Trident Bookstore’s huevos rancheros methinks. But I did find something very shocking, as if I am not reviled enough for all the shocking things I find. That is, self-reviled. That saddens me. And to be fair, I developed a new algorithm a few days ago, which I have been working on, and it is sweet. Noisy, but fabulous. It is an insurance policy on a different planet, as some would say, in the Galactic Federation. or Atlantis. Or GG Land, which is in the capital G of Greenland, like something else I’d like to point out in a future post, which is related to Algeria I think, and a park in New York. At least I can use all this craziness for my job—art stuff. Hence the relatively low salary, but “low” is not a complaint. It is a great job, and I just described why.
(I cache all interesting webpages and back them up on paranoid, oops, cautious servers. It isn’t paranoia, because I can’t experience fear. Hence Amfs’s name.) So I’ve had a busy night.
Clank clank clank whisper, this is MY SCREENPLAY!!! I will eventually write out some of the really early stuff from the green fake snakeskin book (It might have been a fake snake). I had promised not to write anymore, and just put up pictures and pieces of music, but this was kind of exceptional. It is the first time I am cross-posting a message too. Oh, and videos, like ones I will be showing tonight.
Check out my other blog for my name....