diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..10d7849
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,11 @@
+main: clean wasm_exec
+ tinygo build -o ./public/wasm/wasm.wasm -target wasm -no-debug ./wasm/src/autoCorrelate.go
+ # cp ./main/index.html ./html/
+ cp ./wasm/src/wasm.js ./public/wasm/
+
+wasm_exec:
+ cp `tinygo env TINYGOROOT`/targets/wasm_exec.js ./public/wasm
+
+clean:
+ rm -rf ./public/wasm
+ mkdir ./public/wasm
diff --git a/index.html b/index.html
index d2f6839..a98bbce 100644
--- a/index.html
+++ b/index.html
@@ -4,6 +4,8 @@
+
+
Svelte + TS + Vite App
diff --git a/public/wasm/wasm.js b/public/wasm/wasm.js
new file mode 100644
index 0000000..76e4ead
--- /dev/null
+++ b/public/wasm/wasm.js
@@ -0,0 +1,28 @@
+"use strict";
+
+const WASM_URL = "wasm/wasm.wasm";
+
+var wasm;
+
+function init() {
+ const go = new Go();
+ if ("instantiateStreaming" in WebAssembly) {
+ WebAssembly.instantiateStreaming(fetch(WASM_URL), go.importObject).then(
+ function (obj) {
+ wasm = obj.instance;
+ go.run(wasm);
+ }
+ );
+ } else {
+ fetch(WASM_URL)
+ .then((resp) => resp.arrayBuffer())
+ .then((bytes) =>
+ WebAssembly.instantiate(bytes, go.importObject).then(function (obj) {
+ wasm = obj.instance;
+ go.run(wasm);
+ })
+ );
+ }
+}
+
+init();
diff --git a/public/wasm/wasm.wasm b/public/wasm/wasm.wasm
new file mode 100755
index 0000000..f89678c
Binary files /dev/null and b/public/wasm/wasm.wasm differ
diff --git a/public/wasm/wasm_exec.js b/public/wasm/wasm_exec.js
new file mode 100644
index 0000000..8021b44
--- /dev/null
+++ b/public/wasm/wasm_exec.js
@@ -0,0 +1,535 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+//
+// This file has been modified for use by the TinyGo compiler.
+
+(() => {
+ // Map multiple JavaScript environments to a single common API,
+ // preferring web standards over Node.js API.
+ //
+ // Environments considered:
+ // - Browsers
+ // - Node.js
+ // - Electron
+ // - Parcel
+
+ if (typeof global !== "undefined") {
+ // global already exists
+ } else if (typeof window !== "undefined") {
+ window.global = window;
+ } else if (typeof self !== "undefined") {
+ self.global = self;
+ } else {
+ throw new Error("cannot export Go (neither global, window nor self is defined)");
+ }
+
+ if (!global.require && typeof require !== "undefined") {
+ global.require = require;
+ }
+
+ if (!global.fs && global.require) {
+ global.fs = require("fs");
+ }
+
+ const enosys = () => {
+ const err = new Error("not implemented");
+ err.code = "ENOSYS";
+ return err;
+ };
+
+ if (!global.fs) {
+ let outputBuf = "";
+ global.fs = {
+ constants: { O_WRONLY: -1, O_RDWR: -1, O_CREAT: -1, O_TRUNC: -1, O_APPEND: -1, O_EXCL: -1 }, // unused
+ writeSync(fd, buf) {
+ outputBuf += decoder.decode(buf);
+ const nl = outputBuf.lastIndexOf("\n");
+ if (nl != -1) {
+ console.log(outputBuf.substr(0, nl));
+ outputBuf = outputBuf.substr(nl + 1);
+ }
+ return buf.length;
+ },
+ write(fd, buf, offset, length, position, callback) {
+ if (offset !== 0 || length !== buf.length || position !== null) {
+ callback(enosys());
+ return;
+ }
+ const n = this.writeSync(fd, buf);
+ callback(null, n);
+ },
+ chmod(path, mode, callback) { callback(enosys()); },
+ chown(path, uid, gid, callback) { callback(enosys()); },
+ close(fd, callback) { callback(enosys()); },
+ fchmod(fd, mode, callback) { callback(enosys()); },
+ fchown(fd, uid, gid, callback) { callback(enosys()); },
+ fstat(fd, callback) { callback(enosys()); },
+ fsync(fd, callback) { callback(null); },
+ ftruncate(fd, length, callback) { callback(enosys()); },
+ lchown(path, uid, gid, callback) { callback(enosys()); },
+ link(path, link, callback) { callback(enosys()); },
+ lstat(path, callback) { callback(enosys()); },
+ mkdir(path, perm, callback) { callback(enosys()); },
+ open(path, flags, mode, callback) { callback(enosys()); },
+ read(fd, buffer, offset, length, position, callback) { callback(enosys()); },
+ readdir(path, callback) { callback(enosys()); },
+ readlink(path, callback) { callback(enosys()); },
+ rename(from, to, callback) { callback(enosys()); },
+ rmdir(path, callback) { callback(enosys()); },
+ stat(path, callback) { callback(enosys()); },
+ symlink(path, link, callback) { callback(enosys()); },
+ truncate(path, length, callback) { callback(enosys()); },
+ unlink(path, callback) { callback(enosys()); },
+ utimes(path, atime, mtime, callback) { callback(enosys()); },
+ };
+ }
+
+ if (!global.process) {
+ global.process = {
+ getuid() { return -1; },
+ getgid() { return -1; },
+ geteuid() { return -1; },
+ getegid() { return -1; },
+ getgroups() { throw enosys(); },
+ pid: -1,
+ ppid: -1,
+ umask() { throw enosys(); },
+ cwd() { throw enosys(); },
+ chdir() { throw enosys(); },
+ }
+ }
+
+ if (!global.crypto) {
+ const nodeCrypto = require("crypto");
+ global.crypto = {
+ getRandomValues(b) {
+ nodeCrypto.randomFillSync(b);
+ },
+ };
+ }
+
+ if (!global.performance) {
+ global.performance = {
+ now() {
+ const [sec, nsec] = process.hrtime();
+ return sec * 1000 + nsec / 1000000;
+ },
+ };
+ }
+
+ if (!global.TextEncoder) {
+ global.TextEncoder = require("util").TextEncoder;
+ }
+
+ if (!global.TextDecoder) {
+ global.TextDecoder = require("util").TextDecoder;
+ }
+
+ // End of polyfills for common API.
+
+ const encoder = new TextEncoder("utf-8");
+ const decoder = new TextDecoder("utf-8");
+ var logLine = [];
+
+ global.Go = class {
+ constructor() {
+ this._callbackTimeouts = new Map();
+ this._nextCallbackTimeoutID = 1;
+
+ const mem = () => {
+ // The buffer may change when requesting more memory.
+ return new DataView(this._inst.exports.memory.buffer);
+ }
+
+ const setInt64 = (addr, v) => {
+ mem().setUint32(addr + 0, v, true);
+ mem().setUint32(addr + 4, Math.floor(v / 4294967296), true);
+ }
+
+ const getInt64 = (addr) => {
+ const low = mem().getUint32(addr + 0, true);
+ const high = mem().getInt32(addr + 4, true);
+ return low + high * 4294967296;
+ }
+
+ const loadValue = (addr) => {
+ const f = mem().getFloat64(addr, true);
+ if (f === 0) {
+ return undefined;
+ }
+ if (!isNaN(f)) {
+ return f;
+ }
+
+ const id = mem().getUint32(addr, true);
+ return this._values[id];
+ }
+
+ const storeValue = (addr, v) => {
+ const nanHead = 0x7FF80000;
+
+ if (typeof v === "number") {
+ if (isNaN(v)) {
+ mem().setUint32(addr + 4, nanHead, true);
+ mem().setUint32(addr, 0, true);
+ return;
+ }
+ if (v === 0) {
+ mem().setUint32(addr + 4, nanHead, true);
+ mem().setUint32(addr, 1, true);
+ return;
+ }
+ mem().setFloat64(addr, v, true);
+ return;
+ }
+
+ switch (v) {
+ case undefined:
+ mem().setFloat64(addr, 0, true);
+ return;
+ case null:
+ mem().setUint32(addr + 4, nanHead, true);
+ mem().setUint32(addr, 2, true);
+ return;
+ case true:
+ mem().setUint32(addr + 4, nanHead, true);
+ mem().setUint32(addr, 3, true);
+ return;
+ case false:
+ mem().setUint32(addr + 4, nanHead, true);
+ mem().setUint32(addr, 4, true);
+ return;
+ }
+
+ let id = this._ids.get(v);
+ if (id === undefined) {
+ id = this._idPool.pop();
+ if (id === undefined) {
+ id = this._values.length;
+ }
+ this._values[id] = v;
+ this._goRefCounts[id] = 0;
+ this._ids.set(v, id);
+ }
+ this._goRefCounts[id]++;
+ let typeFlag = 1;
+ switch (typeof v) {
+ case "string":
+ typeFlag = 2;
+ break;
+ case "symbol":
+ typeFlag = 3;
+ break;
+ case "function":
+ typeFlag = 4;
+ break;
+ }
+ mem().setUint32(addr + 4, nanHead | typeFlag, true);
+ mem().setUint32(addr, id, true);
+ }
+
+ const loadSlice = (array, len, cap) => {
+ return new Uint8Array(this._inst.exports.memory.buffer, array, len);
+ }
+
+ const loadSliceOfValues = (array, len, cap) => {
+ const a = new Array(len);
+ for (let i = 0; i < len; i++) {
+ a[i] = loadValue(array + i * 8);
+ }
+ return a;
+ }
+
+ const loadString = (ptr, len) => {
+ return decoder.decode(new DataView(this._inst.exports.memory.buffer, ptr, len));
+ }
+
+ const timeOrigin = Date.now() - performance.now();
+ this.importObject = {
+ wasi_snapshot_preview1: {
+ // https://github.com/WebAssembly/WASI/blob/main/phases/snapshot/docs.md#fd_write
+ fd_write: function(fd, iovs_ptr, iovs_len, nwritten_ptr) {
+ let nwritten = 0;
+ if (fd == 1) {
+ for (let iovs_i=0; iovs_i 0, // dummy
+ fd_fdstat_get: () => 0, // dummy
+ fd_seek: () => 0, // dummy
+ "proc_exit": (code) => {
+ if (global.process) {
+ // Node.js
+ process.exit(code);
+ } else {
+ // Can't exit in a browser.
+ throw 'trying to exit with code ' + code;
+ }
+ },
+ random_get: (bufPtr, bufLen) => {
+ crypto.getRandomValues(loadSlice(bufPtr, bufLen));
+ return 0;
+ },
+ },
+ env: {
+ // func ticks() float64
+ "runtime.ticks": () => {
+ return timeOrigin + performance.now();
+ },
+
+ // func sleepTicks(timeout float64)
+ "runtime.sleepTicks": (timeout) => {
+ // Do not sleep, only reactivate scheduler after the given timeout.
+ setTimeout(this._inst.exports.go_scheduler, timeout);
+ },
+
+ // func finalizeRef(v ref)
+ "syscall/js.finalizeRef": (sp) => {
+ // Note: TinyGo does not support finalizers so this should never be
+ // called.
+ console.error('syscall/js.finalizeRef not implemented');
+ },
+
+ // func stringVal(value string) ref
+ "syscall/js.stringVal": (ret_ptr, value_ptr, value_len) => {
+ const s = loadString(value_ptr, value_len);
+ storeValue(ret_ptr, s);
+ },
+
+ // func valueGet(v ref, p string) ref
+ "syscall/js.valueGet": (retval, v_addr, p_ptr, p_len) => {
+ let prop = loadString(p_ptr, p_len);
+ let value = loadValue(v_addr);
+ let result = Reflect.get(value, prop);
+ storeValue(retval, result);
+ },
+
+ // func valueSet(v ref, p string, x ref)
+ "syscall/js.valueSet": (v_addr, p_ptr, p_len, x_addr) => {
+ const v = loadValue(v_addr);
+ const p = loadString(p_ptr, p_len);
+ const x = loadValue(x_addr);
+ Reflect.set(v, p, x);
+ },
+
+ // func valueDelete(v ref, p string)
+ "syscall/js.valueDelete": (v_addr, p_ptr, p_len) => {
+ const v = loadValue(v_addr);
+ const p = loadString(p_ptr, p_len);
+ Reflect.deleteProperty(v, p);
+ },
+
+ // func valueIndex(v ref, i int) ref
+ "syscall/js.valueIndex": (ret_addr, v_addr, i) => {
+ storeValue(ret_addr, Reflect.get(loadValue(v_addr), i));
+ },
+
+ // valueSetIndex(v ref, i int, x ref)
+ "syscall/js.valueSetIndex": (v_addr, i, x_addr) => {
+ Reflect.set(loadValue(v_addr), i, loadValue(x_addr));
+ },
+
+ // func valueCall(v ref, m string, args []ref) (ref, bool)
+ "syscall/js.valueCall": (ret_addr, v_addr, m_ptr, m_len, args_ptr, args_len, args_cap) => {
+ const v = loadValue(v_addr);
+ const name = loadString(m_ptr, m_len);
+ const args = loadSliceOfValues(args_ptr, args_len, args_cap);
+ try {
+ const m = Reflect.get(v, name);
+ storeValue(ret_addr, Reflect.apply(m, v, args));
+ mem().setUint8(ret_addr + 8, 1);
+ } catch (err) {
+ storeValue(ret_addr, err);
+ mem().setUint8(ret_addr + 8, 0);
+ }
+ },
+
+ // func valueInvoke(v ref, args []ref) (ref, bool)
+ "syscall/js.valueInvoke": (ret_addr, v_addr, args_ptr, args_len, args_cap) => {
+ try {
+ const v = loadValue(v_addr);
+ const args = loadSliceOfValues(args_ptr, args_len, args_cap);
+ storeValue(ret_addr, Reflect.apply(v, undefined, args));
+ mem().setUint8(ret_addr + 8, 1);
+ } catch (err) {
+ storeValue(ret_addr, err);
+ mem().setUint8(ret_addr + 8, 0);
+ }
+ },
+
+ // func valueNew(v ref, args []ref) (ref, bool)
+ "syscall/js.valueNew": (ret_addr, v_addr, args_ptr, args_len, args_cap) => {
+ const v = loadValue(v_addr);
+ const args = loadSliceOfValues(args_ptr, args_len, args_cap);
+ try {
+ storeValue(ret_addr, Reflect.construct(v, args));
+ mem().setUint8(ret_addr + 8, 1);
+ } catch (err) {
+ storeValue(ret_addr, err);
+ mem().setUint8(ret_addr+ 8, 0);
+ }
+ },
+
+ // func valueLength(v ref) int
+ "syscall/js.valueLength": (v_addr) => {
+ return loadValue(v_addr).length;
+ },
+
+ // valuePrepareString(v ref) (ref, int)
+ "syscall/js.valuePrepareString": (ret_addr, v_addr) => {
+ const s = String(loadValue(v_addr));
+ const str = encoder.encode(s);
+ storeValue(ret_addr, str);
+ setInt64(ret_addr + 8, str.length);
+ },
+
+ // valueLoadString(v ref, b []byte)
+ "syscall/js.valueLoadString": (v_addr, slice_ptr, slice_len, slice_cap) => {
+ const str = loadValue(v_addr);
+ loadSlice(slice_ptr, slice_len, slice_cap).set(str);
+ },
+
+ // func valueInstanceOf(v ref, t ref) bool
+ "syscall/js.valueInstanceOf": (v_addr, t_addr) => {
+ return loadValue(v_addr) instanceof loadValue(t_addr);
+ },
+
+ // func copyBytesToGo(dst []byte, src ref) (int, bool)
+ "syscall/js.copyBytesToGo": (ret_addr, dest_addr, dest_len, dest_cap, source_addr) => {
+ let num_bytes_copied_addr = ret_addr;
+ let returned_status_addr = ret_addr + 4; // Address of returned boolean status variable
+
+ const dst = loadSlice(dest_addr, dest_len);
+ const src = loadValue(source_addr);
+ if (!(src instanceof Uint8Array || src instanceof Uint8ClampedArray)) {
+ mem().setUint8(returned_status_addr, 0); // Return "not ok" status
+ return;
+ }
+ const toCopy = src.subarray(0, dst.length);
+ dst.set(toCopy);
+ setInt64(num_bytes_copied_addr, toCopy.length);
+ mem().setUint8(returned_status_addr, 1); // Return "ok" status
+ },
+
+ // copyBytesToJS(dst ref, src []byte) (int, bool)
+ // Originally copied from upstream Go project, then modified:
+ // https://github.com/golang/go/blob/3f995c3f3b43033013013e6c7ccc93a9b1411ca9/misc/wasm/wasm_exec.js#L404-L416
+ "syscall/js.copyBytesToJS": (ret_addr, dest_addr, source_addr, source_len, source_cap) => {
+ let num_bytes_copied_addr = ret_addr;
+ let returned_status_addr = ret_addr + 4; // Address of returned boolean status variable
+
+ const dst = loadValue(dest_addr);
+ const src = loadSlice(source_addr, source_len);
+ if (!(dst instanceof Uint8Array || dst instanceof Uint8ClampedArray)) {
+ mem().setUint8(returned_status_addr, 0); // Return "not ok" status
+ return;
+ }
+ const toCopy = src.subarray(0, dst.length);
+ dst.set(toCopy);
+ setInt64(num_bytes_copied_addr, toCopy.length);
+ mem().setUint8(returned_status_addr, 1); // Return "ok" status
+ },
+ }
+ };
+ }
+
+ async run(instance) {
+ this._inst = instance;
+ this._values = [ // JS values that Go currently has references to, indexed by reference id
+ NaN,
+ 0,
+ null,
+ true,
+ false,
+ global,
+ this,
+ ];
+ this._goRefCounts = []; // number of references that Go has to a JS value, indexed by reference id
+ this._ids = new Map(); // mapping from JS values to reference ids
+ this._idPool = []; // unused ids that have been garbage collected
+ this.exited = false; // whether the Go program has exited
+
+ const mem = new DataView(this._inst.exports.memory.buffer)
+
+ while (true) {
+ const callbackPromise = new Promise((resolve) => {
+ this._resolveCallbackPromise = () => {
+ if (this.exited) {
+ throw new Error("bad callback: Go program has already exited");
+ }
+ setTimeout(resolve, 0); // make sure it is asynchronous
+ };
+ });
+ this._inst.exports._start();
+ if (this.exited) {
+ break;
+ }
+ await callbackPromise;
+ }
+ }
+
+ _resume() {
+ if (this.exited) {
+ throw new Error("Go program has already exited");
+ }
+ this._inst.exports.resume();
+ if (this.exited) {
+ this._resolveExitPromise();
+ }
+ }
+
+ _makeFuncWrapper(id) {
+ const go = this;
+ return function () {
+ const event = { id: id, this: this, args: arguments };
+ go._pendingEvent = event;
+ go._resume();
+ return event.result;
+ };
+ }
+ }
+
+ if (
+ global.require &&
+ global.require.main === module &&
+ global.process &&
+ global.process.versions &&
+ !global.process.versions.electron
+ ) {
+ if (process.argv.length != 3) {
+ console.error("usage: go_js_wasm_exec [wasm binary] [arguments]");
+ process.exit(1);
+ }
+
+ const go = new Go();
+ WebAssembly.instantiate(fs.readFileSync(process.argv[2]), go.importObject).then((result) => {
+ return go.run(result.instance);
+ }).catch((err) => {
+ console.error(err);
+ process.exit(1);
+ });
+ }
+})();
diff --git a/src/lib/Tuner.svelte b/src/lib/Tuner.svelte
index cd3c272..99c4fd0 100644
--- a/src/lib/Tuner.svelte
+++ b/src/lib/Tuner.svelte
@@ -202,11 +202,19 @@
// array for received buffer of audio
let buflen = 2048;
let buf = new Float32Array(buflen);
-
// updates the note using requestAnimationFrame
function updatePitch() {
+ const wasmMemory = new Float32Array(wasm.exports.memory.buffer);
+ const wasmMemoryPtr = wasm.exports.getBufferPointer();
+
+ // Get a slice of the wasm memory that points to the buffer created in Go.
+ // Since the buffer is a Float32Array, we need to divide the byte offset by 4. (4 bytes per float)
+ wasmMemory.set(buf, wasmMemoryPtr / wasmMemory.BYTES_PER_ELEMENT);
+
+ // Copy the current audio to buf. Since we set the buffer location to the wasm memory, it's accessible from Go.
analyser.getFloatTimeDomainData(buf);
- let ac = autoCorrelate(buf, audioContext.sampleRate);
+ // It may be more clear to pass a pointer to autoCorrelate, instead of using closures in Go.
+ let ac = wasm.exports.autoCorrelate(audioContext.sampleRate, sensitivity);
if (ac == -1) {
// note was ignored
diff --git a/wasm/src/autoCorrelate.go b/wasm/src/autoCorrelate.go
new file mode 100644
index 0000000..ec0f3df
--- /dev/null
+++ b/wasm/src/autoCorrelate.go
@@ -0,0 +1,106 @@
+package main
+
+import (
+ "fmt"
+ "math"
+)
+
+// Create a byte (float32, not Go byte) buffer, which will be available in Wasm Memory.
+// We can then share this buffer with JS and Wasm.
+const BUFFER_SIZE int = 2048
+
+var buf [BUFFER_SIZE]float32
+
+func main() {
+ fmt.Println("call wasm.exports.autoCorrelate() from JS in the browser:")
+}
+
+// GetBufferPointer returns a pointer (index) to our buffer in wasm memory.
+//
+//export getBufferPointer
+func getBufferPointer() *[BUFFER_SIZE]float32 {
+ return &buf
+}
+
+// GetBufferSize returns the size of our buffer in wasm memory.
+//
+//export getBufferSize
+func getBufferSize() int {
+ return BUFFER_SIZE
+}
+
+type Pitch float32
+
+var octaveLen = 7.0
+
+//export autoCorrelate
+func autoCorrelate(sampleRate, thres float64) Pitch {
+ size := len(buf)
+ rms := float64(0.0)
+ for _, v := range buf {
+ val := float64(v)
+ rms += val * val
+ }
+ rms = math.Sqrt(rms / float64(size))
+ if rms < thres {
+ return -1
+ }
+
+ r1 := 0
+ r2 := size - 1
+
+ for i := 0; i < size/2; i++ {
+ if math.Abs(float64(buf[i])) < thres {
+ r1 = i
+ break
+ }
+ }
+
+ for i := 1; i < size/2; i++ {
+ if math.Abs(float64(buf[size-i])) < thres {
+ r2 = size - i
+ break
+ }
+ }
+
+ bufSample := buf[r1:r2]
+ size = len(bufSample)
+
+ c := make([]float32, size)
+ for i := 0; i < size; i++ {
+ for j := 0; j < size-i; j++ {
+ c[i] = c[i] + bufSample[j]*bufSample[j+i]
+ }
+ }
+
+ d := 0
+ for d < size-2 && c[d] > c[d+1] {
+ d++
+ }
+
+ maxVal := -1.0
+ maxPos := -1
+
+ for i := d; i < size; i++ {
+ if float64(c[i]) > maxVal {
+ maxVal = float64(c[i])
+ maxPos = i
+ }
+ }
+
+ t0 := maxPos
+
+ // Handle case when d is already out-of-bounds of c
+ if maxPos < 1 {
+ return -1
+ }
+
+ x1 := c[t0-1]
+ x2 := c[t0]
+ x3 := c[t0+1]
+
+ a := float64((x1 + x3 - 2*x2) / 2)
+ b := float64((x3 - x1) / 2)
+
+ return Pitch(sampleRate / (float64(t0) - b/(2*a)))
+}
diff --git a/wasm/src/wasm.js b/wasm/src/wasm.js
new file mode 100644
index 0000000..76e4ead
--- /dev/null
+++ b/wasm/src/wasm.js
@@ -0,0 +1,28 @@
+"use strict";
+
+const WASM_URL = "wasm/wasm.wasm";
+
+var wasm;
+
+function init() {
+ const go = new Go();
+ if ("instantiateStreaming" in WebAssembly) {
+ WebAssembly.instantiateStreaming(fetch(WASM_URL), go.importObject).then(
+ function (obj) {
+ wasm = obj.instance;
+ go.run(wasm);
+ }
+ );
+ } else {
+ fetch(WASM_URL)
+ .then((resp) => resp.arrayBuffer())
+ .then((bytes) =>
+ WebAssembly.instantiate(bytes, go.importObject).then(function (obj) {
+ wasm = obj.instance;
+ go.run(wasm);
+ })
+ );
+ }
+}
+
+init();