webcodecs: Connect AudioEncoder to underlying encoder implementation
At this point only Opus encoding is supported.
Bug: 1094181, 1094179
Change-Id: I05b22bcbd29e96b3823d00dbf85f007936678751
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2625822
Reviewed-by: Dan Sanders <sandersd@chromium.org>
Commit-Queue: Eugene Zemtsov <eugene@chromium.org>
Cr-Commit-Position: refs/heads/master@{#843360}
diff --git a/webcodecs/audio-encoder.any.js b/webcodecs/audio-encoder.any.js
new file mode 100644
index 0000000..1672993
--- /dev/null
+++ b/webcodecs/audio-encoder.any.js
@@ -0,0 +1,67 @@
+// META: global=window
+// META: script=/webcodecs/utils.js
+
+function make_audio_frame(timestamp, channels, sampleRate, length) {
+ let buffer = new AudioBuffer({
+ length: length,
+ numberOfChannels: channels,
+ sampleRate: sampleRate
+ });
+
+ for (var channel = 0; channel < buffer.numberOfChannels; channel++) {
+ // This gives us the actual array that contains the data
+ var array = buffer.getChannelData(channel);
+ let hz = 100 + channel * 50; // sound frequency
+ for (var i = 0; i < array.length; i++) {
+ let t = (i / sampleRate) * hz * (Math.PI * 2);
+ array[i] = Math.sin(t);
+ }
+ }
+
+ return new AudioFrame({
+ timestamp: timestamp,
+ buffer: buffer
+ });
+}
+
+promise_test(async t => {
+ let frame_count = 100;
+ let outputs = [];
+ let init = {
+ error: e => {
+ assert_unreached("error: " + e);
+ },
+ output: chunk => {
+ outputs.push(chunk);
+ }
+ };
+
+ let encoder = new AudioEncoder(init);
+
+ assert_equals(encoder.state, "unconfigured");
+ let config = {
+ codec: 'opus',
+ sampleRate: 48000,
+ numberOfChannels: 2,
+ bitrate: 256000 //256kbit
+ };
+
+ encoder.configure(config);
+
+ let timestamp = 0;
+ for (let i = 0; i < frame_count; i++) {
+ // one tenth of a seconds per frame
+ let length = config.sampleRate / 10;
+ timestamp += 100_000;
+ let frame = make_audio_frame(timestamp, config.numberOfChannels,
+ config.sampleRate, length);
+ encoder.encode(frame);
+ }
+ await encoder.flush();
+ encoder.close();
+ assert_greater_than_equal(outputs.length, frame_count);
+ for (chunk of outputs) {
+ assert_greater_than(chunk.data.byteLength, 0);
+ assert_greater_than(timestamp, chunk.timestamp);
+ }
+}, 'Simple audio encoding');
