commit 3bbe514f09fcd6241bac429bef8a36860a0e2732
author Thomas Guilbert <tguilbert@chromium.org> Thu Aug 20 21:08:36 2020
committer Blink WPT Bot <blink-w3c-test-autoroller@chromium.org> Thu Aug 20 22:21:49 2020
tree 72938d392daaf99e52ca6086bd1dfb6168521345
parent 2a6fafe37fc556c5382d45cc553f825f91331e34

Copy and destroy frames on encode()

This CL changes the behavior of VideoEncoder to make an internal copy
of frames passed in through encode(), before destroying the passed
frame. This means that users don't need to call destroy() after passing
frames to encode(), which could result in a frame being invalidated
before we send it to the internal encoder. It also means we can destroy
the frame internally when we no longer need it without risking that it
might still be in use by the user.

Users that which to keep their frames alive after giving them to the
encoder can send a cloned copy instead.

Bug: 1108023
Change-Id: Ie5cd98d688a53314ac16a6a3ac7afe2a65d742f8
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2363863
Commit-Queue: Thomas Guilbert <tguilbert@chromium.org>
Reviewed-by: Dan Sanders <sandersd@chromium.org>
Cr-Commit-Position: refs/heads/master@{#800296}

webcodecs/video-encoder.html

diff --git a/webcodecs/video-encoder.html b/webcodecs/video-encoder.html
index 61f0d33..b56e7d1 100644
--- a/webcodecs/video-encoder.html
+++ b/webcodecs/video-encoder.html
@@ -134,8 +134,8 @@
   let frame1 = await createVideoFrame(640, 480, 0);
   let frame2 = await createVideoFrame(640, 480, 33333);
 
-  encoder.encode(frame1);
-  encoder.encode(frame2);
+  encoder.encode(frame1.clone());
+  encoder.encode(frame2.clone());
 
   // Could be 0, 1, or 2. We can't guarantee this check runs before the UA has
   // processed the encodes.
@@ -176,10 +176,10 @@
   let frame1 = await createVideoFrame(640, 480, 0);
   let frame2 = await createVideoFrame(640, 480, 33333);
 
-  encoder.encode(frame1);
+  encoder.encode(frame1.clone());
   encoder.configure(config);
 
-  encoder.encode(frame2);
+  encoder.encode(frame2.clone());
 
   await encoder.flush();
 
@@ -206,13 +206,13 @@
   let frame3 = await createVideoFrame(640, 480, 66666);
   let frame4 = await createVideoFrame(640, 480, 100000);
 
-  encoder.encode(frame3);
+  encoder.encode(frame3.clone());
 
   // Verify that a failed call to configure does not change the encoder's state.
   config.codec = 'bogus';
   assert_throws_js(TypeError, () => encoder.configure(config));
 
-  encoder.encode(frame4);
+  encoder.encode(frame4.clone());
 
   await encoder.flush();
 
@@ -224,5 +224,38 @@
   asyncDone(t);
 }, 'Test successful encode() after re-configure().');
 
+async_test(async (t) => {
+  let output_chunks = [];
+  let encoder = new VideoEncoder({
+    output(chunk) { output_chunks.push(chunk); },
+    error(error) { t.unreached_func("Unexpected error:" + error).call(); },
+  });
+
+  let timestamp = 33333;
+  let frame = await createVideoFrame(640, 480, timestamp);
+
+  t.step(() => {
+    // No encodes yet.
+    assert_equals(encoder.encodeQueueSize, 0);
+
+    const config = {
+      codec: 'vp8',
+      framerate: 25,
+      width: 640,
+      height: 480
+    };
+    encoder.configure(config);
+
+    encoder.encode(frame);
+
+    assert_not_equals(frame.timestamp, timestamp);
+    assert_throws_dom("InvalidStateError", () => frame.clone());
+
+    encoder.close();
+  });
+
+  asyncDone(t);
+}, 'Test encoder consumes (destroys) frames.');
+
 </script>
 </html>