npm : add README.md

bindings/javascript/README.md

@@ -0,0 +1,32 @@
+# ggwave
+
+Tiny data-over-sound library.
+
+- Audible and ultrasound transmissions available
+- Bandwidth of 8-16 bytes/s (depending on the transmission protocol)
+- Robust FSK modulation
+- Reed-Solomon based error correction
+
+## Example Usage
+
+```js
+var factory = require('ggwave')
+
+factory().then(function(ggwave) {
+    // create ggwave instance with default parameters
+    var parameters = ggwave.getDefaultParameters();
+    var instance = ggwave.init(parameters);
+
+    var payload = 'hello js';
+
+    // generate audio waveform for string "hello js"
+    var waveform = ggwave.encode(instance, payload, ggwave.TxProtocolId.GGWAVE_TX_PROTOCOL_AUDIBLE_FAST, 10);
+
+    // decode the audio waveform back to text
+    var res = ggwave.decode(instance, waveform);
+
+    if (res != payload) {
+        process.exit(1);
+    }
+});
+```