diff options
Diffstat (limited to 'client/draw.js')
| -rw-r--r-- | client/draw.js | 112 |
1 files changed, 32 insertions, 80 deletions
diff --git a/client/draw.js b/client/draw.js index 3dab322..bed5f80 100644 --- a/client/draw.js +++ b/client/draw.js @@ -1,7 +1,3 @@ -import Tone from 'tone' - -import output from './lib/output' - import { browser, requestAudioContext, randint, randrange, clamp, mod, @@ -13,9 +9,14 @@ import color from './lib/color' let w, h let rx, ry +const pixels_per_second = 1024 + const canvas = document.createElement('canvas') const ctx = canvas.getContext('2d') +const scratch = document.createElement('canvas') +const scratchCtx = scratch.getContext('2d') + document.body.appendChild(canvas) document.body.addEventListener('resize', resize) resize() @@ -94,7 +95,6 @@ function waveform(pcm, sr, pos, zoom){ var x0 = 0 var y0 = 20 var ymid = y0 + half_height - var pixels_per_second = 1024 var max_width_in_seconds = width / pixels_per_second var max_width_in_samples = max_width_in_seconds * sr var pcm_length = pcm.length @@ -120,69 +120,22 @@ function waveform(pcm, sr, pos, zoom){ ctx.restore() } -const signalWindows = require('signal-windows').windows -const FFTJS = require('fft.js') -const fft_size = 2048 -const fft_overlap = fft_size / 4 -const half_fft_size = fft_size / 2 -const fft = new FFTJS(fft_size) +function spectrum(spec, x0, y0, ww, hh){ + const data = spec.data + const fft_size = spec.fft_size + const half_fft_size = spec.fft_size / 2 + const spec_len = data.length -function toSpectrum(pcm){ - const ham = signalWindows.construct('ham', fft_size) - const pcm_in = new Array(fft_size) - const pcm_length = pcm.length - const pcm_q_length = Math.ceil(pcm_length / fft_size) * fft_size - let i, j, fft_out, spec = []; - for (i = 0; i < pcm_q_length; i += fft_overlap) { - for (j = 0; j < fft_size; j++) { - pcm_in[j] = pcm[i+j] * ham[j] || 0 - } - fft_out = fft.createComplexArray() - fft.realTransform(fft_out, pcm_in) - fft.completeSpectrum(fft_out) - spec.push(fft_out) - } - return spec -} -function fromSpectrum(spec, sr){ - const spec_len = spec.length - const ham = signalWindows.construct('ham', fft_size) - const out = fft.createComplexArray() - const pcm_length = fft_overlap * spec_len - const audioBuffer = Tone.context.createBuffer(1, pcm_length, sr) - const pcm = audioBuffer.getChannelData(0); - let i, j, u, v, _r, _i, col - for (i = 0; i < spec_len; i++) { - col = spec[i] - fft.inverseTransform(out, col) - u = i * (fft_overlap) - for (j = fft_size * 1/4; j < fft_size * 3/4; j++) { - pcm[u+j] = out[j*2] / ham[j] || 0 - } - } - const player = new Tone.Player(audioBuffer) - player.connect(output) - player.start(Tone.now() + pcm_length / sr) - // console.log(Tone.now() + pcm_length / sr) - return audioBuffer -} -function spectrum(pcm, sr){ - sr = sr || 44100 - const spec = toSpectrum(pcm) - - ctx.save() - - const scratch = document.createElement('canvas') - scratch.width = spec.length + scratch.width = data.length scratch.height = half_fft_size - const scratchCtx = scratch.getContext('2d') var imageData = ctx.createImageData(scratch.width, scratch.height) - var data = imageData.data + var pixels = imageData.data + + let i, j, u, v, _r, _i, col, hsl - let i, j, u, v, _r, _i, col, hsl, spec_len = spec.length for (i = 0; i < spec_len; i++) { - col = spec[i] + col = data[i] for (j = 0; j < half_fft_size; j++) { u = ((half_fft_size - j) * spec_len + i) * 4 @@ -191,36 +144,35 @@ function spectrum(pcm, sr){ _i = mod(col[v+1], Math.PI*2) / (Math.PI*2) hsl = color.hsl2rgb((_i + 1) / 2, 1.0, 1 - Math.abs(_r / 10)) // red - real part - // data[u] = _r * 127 + 127 + // pixels[u] = _r * 127 + 127 // // green - imag part - // data[u+1] = _i * 127 + 127 + // pixels[u+1] = _i * 127 + 127 // // blue - magnitude - // data[u+2] = Math.sqrt(Math.pow(_r, 2) + Math.pow(_i, 2)) * 128 + 127 - // data[u+3] = 255 - data[u] = hsl[0] - data[u+1] = hsl[1] - data[u+2] = hsl[2] - data[u+3] = 255 + // pixels[u+2] = Math.sqrt(Math.pow(_r, 2) + Math.pow(_i, 2)) * 128 + 127 + // pixels[u+3] = 255 + pixels[u] = hsl[0] + pixels[u+1] = hsl[1] + pixels[u+2] = hsl[2] + pixels[u+3] = 255 } } scratchCtx.putImageData(imageData, 0, 0) - var pcm_length = pcm.length - var pixels_per_second = 1024 + var pcm_length = spec.fft_overlap * spec_len + + x0 = x0 || 0 + y0 = y0 || Math.floor(h/4) + ww = ww || window.innerWidth + hh = hh || h/4 - const width = Math.round(pcm_length / sr * pixels_per_second) // ok not really this - const height = Math.floor(h*2/3) + const width = Math.round(pcm_length / spec.sr * pixels_per_second) + const height = Math.floor(hh) - const x0 = 0 - const y0 = Math.floor(h/4) + 20 + ctx.save() clear(1, x0, y0, w, height) ctx.drawImage(scratch, x0, y0, width, height) - ctx.restore() - - const new_pcm = fromSpectrum(spec, sr) - console.log(new_pcm) } export default { |
