Add rsf2wav.js

.gitignore

@@ -31,3 +31,5 @@ videos/**
 lib/
 .vscode/
 bin
+out.wav
+

scripts/rsf2wav.js

@@ -0,0 +1,46 @@
+#!/usr/bin/env node
+
+const fs = require("fs")
+const rsf = fs.readFileSync(process.argv[2])
+
+const fmt = rsf.readInt16BE(0) // 0x0100
+if (fmt != 0x0100) {
+    throw new Error("Invalid input format: " + fmt)
+}
+const size = rsf.readInt16BE(2)
+const samplerate = rsf.readInt16BE(4)
+const repeat = rsf.readInt16BE(6)
+
+const datasize = rsf.length - 8
+
+const wavHd = new Buffer(44)
+
+function writeMark(off, mark) {
+    for (let i = 0; i < mark.length; ++i) {
+        wavHd[off + i] = mark.charCodeAt(i)
+    }
+}
+
+writeMark(0, 'RIFF')
+wavHd.writeInt32LE(datasize + 36, 4)
+writeMark(8, 'WAVE')
+writeMark(12, 'fmt ')
+wavHd.writeInt32LE(16, 16) // fmt size
+wavHd.writeInt16LE(1, 20) // PCM
+wavHd.writeInt16LE(1, 22) // mono, 1ch
+wavHd.writeInt32LE(samplerate, 24)
+wavHd.writeInt32LE(samplerate, 28) // byterate
+wavHd.writeInt16LE(1, 32) // block align
+wavHd.writeInt16LE(8, 34) // bits per sample
+writeMark(36, 'data')
+wavHd.writeInt32LE(datasize, 40)
+
+const wav = Buffer.concat([wavHd, rsf.slice(8)])
+
+console.log("writing out.wav")
+fs.writeFileSync("out.wav", wav)
+
+if (require("os").platform() == "darwin")
+    require('child_process').execSync("afplay out.wav")
+
+// TODO also play on Windows