Prompts used to develop waveloop, as written about here: https://neynt.ca/writing/waveloop/ https://saltblock.neynt.ca/waveloop.html I refer to "mr claude" here in the third person as I interacted with Claude Code through my Claw-like assistant (kanoko). --- me: @kanoko use claude to implement a web-based music visualizer called "waveloop" in saltblock. you can put in a youtube url, and it will play it embedded and display a basic visualization of the audio in the video, drawn using a custom gl shader (or whatever it is that lets you get high performance live rendered graphics in the browser). me: ok nice lovely. now here's my idea for an audio visualizer: i want it to reveal the music's melodic and harmonic structure. to do this, i want you to wrap the space of sound frequecies around a circle by log2(freq) mod 1. use different colors to depict different octaves. audio content at higher frequencies can be depicted by thinner strands as well -- i assume the frequency resolution is just a bit better up there too? whatever i trust you to come up with something that uses the circle but allows the musical signal to carry through across octaves, and also not get drowned by overtones. i want the recent history of the song's audio content to be displayed as a radially expanding trail of maybe 5 seconds long. also overlay the 12 diatonic note names (A, A#...) around the circle so i can tell what is what. and also attempt to detect the current chord and display that too. one key insight here is that all chords of a certain quality and their inversions are just rotations of each other. see what mr claude say to that. me: mr claude a little slow isnt he kanoko: mr claude died at the finish line because of a session limit. me: mr claude has been revived with a fresh infusion of us dollars could you resume the session and make sure that it's all wrapped up me: some feedback: - it seems too quantized right now. i do want the visualization to mostly reflect the raw frequency content with high fidelity, without overly interpreting note or pitch boundaries - there are only two colors, blue and orange? can we draw one of those spirals through a perceptually linear color space to get a high-resolution chromatic channel to convey pitch information through. continuous color btw; don't use the floored divide to quantize colors or anything! - can we make the trails pulse out faster near the center and slow down outward? me: so i'd actually like hue to slowly shift from 20hz to 20000hz logarithmically. angular position already conveys pitch class; we don't need hue to convey the same thing. we need hue to convey absolute pitch as distinct from pitch class; let's say, red=low, violet=high. me: would it be possible to drastically increase the temporal and spatial resolution of this analysis? me: cool yeah let's crank each knob a bit. i don't mind expensive, i want quality. if we need to start preprocessing somewhat that's fine. me: there is some latency; the visual updates visibly later than i hear the sound. can you try to sync up the music and the analyzer by adding a delay? me: - get rid of the youtube url; it's fake - can we expand the analysis hz range to encompass 20-20000Hz? me: no need to make the tonic orange with the chord detection or whatever that is doing righ tnow me: let's get rid of the blinking from the logo (the whole logo, really) and the idle indicator me: can we make the visualization do a better job of: - normalizing between quiet and loud parts of songs - stacking different colors on top of each other when the same pitch class exists in multiple octaves let's also get rid of the bass ring that blasts outward; make it more subtle me: we may have overdone the precision. let's do 256 bins per octave? what are we at now? me: let's do it. what exactly is the math that makes it so that we can do a constant number of buckets per semitone? me: ok but. fft gives you linearly spaced buckets right? so you get hella resolution up top and no resolution down below? me: ok. have a claude take a look at some offline cqt approach. in parallel i'm going to propose some separate improvements me: i think megalovania looks a bit like a mess now because the square wave have very strong harmonics... is there any way we could heuristically attenuate harmonics? SAIKAI looks beautiful though. i think let's have the base mode involve very little postprocessing of the spectrogram and have a bunch of toggles and knobs for increasing levels of postprocessing to try to extract the perceptual content out of them. also let claude decide on a few more heuristics too me: what is the hue difference between two successive octaves rn? me: damn ok. can we actually have successive octaves sweep out about 60 degrees? plus lightness increase as the frequency gets higher. also can we adjust by some phon-like scale to convert sound energy to human perception units? me: oh my god i'm about to hit my 5x plan limits. keep it going in 3h when the limits reset please thanks. me: let’s have mr claude wire up the cqt to the frontend me: i trust mr claude. let’s do all that. also version control this if it isn’t already me: ok this is looking quite good so far!! next step: i want it to be easier to tell when energy at the same pitch class is present in different octaves. right now, as i understand it, the energy's colors are blended together. i'd actually like them to be stacked on top of each other in the central circle, much like you might see in a stacked histogram. i would also like the emanating "energy" from higher frequency sounds to launch out faster than that from lower energy sounds, so that they can be visually distinguished through time. can we get this done? me: once that's done: let's also greatly expand the range with which the central ring's energy shoots out. it should basically encompass the whole browser window without fading away. me: queue this up too: we actually want to correlate the speed of ejection with the amplitude, not the pitch. i think that could be more interesting because the loudest frequencies will then get shot out faster and you can identify the "main line" that way 🙂 me: this too: - in mic mode especially, and maybe just all modes, it would be nice to have some even more adaptive gain, maybe up to 10x linear gain / 20dB. if the signal is tiny we don't want to boost it up to 0dbfs of course; be reasonable about it. but like, more dynamic range compression just so we can see interesting things even when i'm speaking into my mic and it's technically a very quiet signal me: ok two more. - i'm noticing the stacked histogram cap out at some max threshold right now. i think we should be willing to allow it to go way higher without normalizing too much. - can we adjust the color scale so that at the bass end, we have darker values, and at the treble end of things, we have lighter values? right now it's a little harder to distinguish what is bass vs what is sparkly little treble or overtones. it'd be nice if the fully saturated and mid-lightness (oklch wise) colors center around the fundamentals of notes typically used in music me: ok a few more waveloop requests! - the energy shooting out is rather pixelly, and emanates in discrete columns. can we have it smoothly interpolate? - i think given that we have stacked histograms now, overtone cut is actually less important and can hide interesting info if there is a strong bassline. let's reduce it in the melodic preset me: also queue up for the main waveloop: - let's get rid of the "chroma match percent" - can we try to make it a bit more mobile friendly. it's already very decent but the overlapping deck and dsp are annoying to navigate by thumb - let's get rid of the demo and tap tempo and references to bpm. i don't think we're gonna do automatic bpm detection. and also the text that appears in the bottom-right "cqt mode" and the "state playing" stuff -- all feels unnecessary. we simplify. me: hate to be the bearer of bad news but i don't think the trails are actually smoothed. actually i think the central circular stacked histogram actually feels a bit less smooth to me now me: so i agree the stacked histograms are nice and smooth now! but i'm talking about the trail that emanates outward. it's still pixelly af for me; uncharacteristically so given how smooth the histogram now is. is that a separate code path, and could we add similar smoothing to it too? me: the recatngular teeth remain. am i understanding correctly that the energy emissions are rendered in some sort of texture where each bin is a single pixel wide? we might need to do our own linear interpolation and use a (slightly) higher res texture me: i think the stacked circular histogram is not quite what i want. i think it's right now a bunch of layered histogram layers, each with a solid color, one per octave, with discrete cuts between octaves. i would rather have a spiral whose color gradually changes. first ask claude if they agree with this assessment. if so then let's adjust it. otherwise let me know where i'm going wrong. me: I don't think that worked very well. The new rim now seems to be a number of concentric rings. It's still not a spiral. Can we revert to the old rim? The one difference I want is that instead of discrete bands, I just want one continuous spiral going out. Everything else about the old rim should stay the same. We shouldn't partition the frequency space into discrete octaves. We should just let all the frequencies belonging to a particular pitch class stack up together at a particular angle. The color should transition through that OKLCH spiral smoothly instead of us sampling a couple discrete points.