Add the audioworklet processor to output audio

worklet-processor.js

+class Processor extends AudioWorkletProcessor {
+    constructor() {
+        super();
+        this.port.onmessage = e => {
+            if (e.data.type === "recv-audio-queue") {
+                this.buf = e.data.data;
+                this.capacity = e.data.sab_size / 4;
+                this.head = new Uint32Array(this.buf, e.data.sab_ptr, 1);
+                this.tail = new Uint32Array(this.buf, e.data.sab_ptr + 4, 1);
+                this.storage = new Float32Array(this.buf, e.data.sab_ptr + 8, this.capacity);
+            } else {
+                throw "unexpected.";
+            }
+        };
+    }
+
+    process(inputs, outputs, parameters) {
+        const output = outputs[0];
+        const nbChannels = output.length;
+        const nbSamples = output[0].length;
+
+        // The pointer that is writen by the VLC audio output.
+        var head = Atomics.load(this.head, 0) / 4;
+        // The pointer that is read here.
+        var tail = Atomics.load(this.tail, 0) / 4;
+
+        var i = 0;
+        /* We read and increment the tail until we reach the head. */
+        while (tail != head && i < nbSamples)
+        {
+            /* Samples are interleaved in the storage.
+               We must separate them by channel. */
+            for (let c = 0; c < nbChannels; ++c) {
+                output[c][i] = this.storage[tail];
+                tail++;
+                if (tail == this.capacity) {
+                    /* We are at the end of the ring buffer
+                       We must return to the start. */
+                    tail = 0;
+                }
+            }
+            i++;
+        }
+        Atomics.store(this.tail, 0, tail * 4);
+
+        return true; // Mark for GC
+    }
+}
+
+registerProcessor("worklet-processor", Processor);