media sonification

1 files changed, 117 insertions, 0 deletions

diff --git a/bin/media.js b/bin/media.js
new file mode 100644
index 0000000..b8742ac
--- /dev/null
+++ b/bin/media.js
@@ -0,0 +1,117 @@
+const fs = require('fs')
+const parse = require('csv-parse')
+const stringify = require('csv-stringify')
+
+const parklandInput = fs.createReadStream('./data/media_01_parkland_shooting.csv')
+const averageInput = fs.createReadStream('./data/media_02_average_of_seven_shootings.csv')
+const parklandParser = parse()
+const averageParser = parse()
+const stringifier = stringify()
+const output = fs.createWriteStream('./data/media.csv')
+
+let finishCount = 0
+let parkland = [], average = []
+function finish() {
+  finishCount += 1
+  console.log(finishCount)
+  if (finishCount < 2) { return }
+  console.log('finishing')
+  let a, b, nn
+  for (let n = 0; n < 12 * 8; n += 1) {
+    nn = n / 8
+    a = find(nn, parkland)
+    b = find(nn, average)
+    stringifier.write([n, a, b])
+  }
+  stringifier.end()
+}
+
+/*
+  Given the sequence A of pairs (i,j) describing coordinates and an offset n,
+  find i where A[i][0] <= n and n < A[i+1][0]
+  and use these to interpolate the value of A(n) -> j or whatever you call it.
+*/
+function find(n, a) {
+  let head, tail, dist
+  for (let i = 1, len = a.length; i < len; i++) {
+    if (a[i][0] > n) {
+      head = a[i-1]
+      tail = a[i]
+      dist = (n - head[0]) / (tail[0] - head[0])
+      console.log(n, head, tail)
+      return lerp(dist, head[1], tail[1])
+    }
+  }
+}
+function lerp(n, a, b) {
+  return (b-a) * n + a
+}
+
+parklandInput.on('readable', function() {
+  let buf
+  while ((buf = parklandInput.read()) !== null) {
+    parklandParser.write(buf)
+  }
+})
+parklandInput.on('error', function(err){
+  console.error('parklandInput error', err.message)
+})
+parklandInput.on('finish', function(){
+  parklandParser.end()
+})
+
+averageInput.on('readable', function() {
+  let buf
+  while ((buf = averageInput.read()) !== null) {
+    averageParser.write(buf)
+  }
+})
+averageInput.on('error', function(err){
+  console.error('averageInput error', err.message)
+})
+averageInput.on('finish', function(){
+    console.log('enddd')
+  averageParser.end()
+})
+
+parklandParser.on('readable', function(){
+  let row
+  while (row = parklandParser.read()) {
+    parkland.push(row.map(n => parseFloat(n)))
+  }
+  // console.log('p', parkland.length)
+  if (parkland.length == 108) finish()
+})
+parklandParser.on('error', function(err){
+  console.error('parklandParser error', err.message)
+})
+parklandParser.on('end', function(){
+  finish()
+})
+
+averageParser.on('readable', function(){
+  let row
+  while (row = averageParser.read()) {
+    average.push(row.map(n => parseFloat(n)))
+  }
+  if (average.length == 89) finish()
+})
+averageParser.on('error', function(err){
+  console.error('averageParser error', err.message)
+})
+averageParser.on('end', function(){
+  finish()
+})
+
+stringifier.on('readable', function(){
+  let row
+  while (row = stringifier.read()){
+    output.write(row)
+  }
+})
+stringifier.on('error', function(err){
+  console.error('stringifier error', err.message)
+})
+stringifier.on('finish', function(){
+  output.end()
+})