Adding third_party/openh264/src, build files and unittests

content/browser/media/openh264_unittests.cc

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "testing/gtest/include/gtest/gtest.h"
+
+#include "third_party/openh264/testing/h264_codec_tester.h"
+#include "third_party/openh264/testing/h264_decoder_impl.h"
+#include "third_party/openh264/testing/h264_encoder_impl.h"
+#include "third_party/openh264/testing/i420_utils.h"
+#include "third_party/webrtc/common_video/libyuv/include/webrtc_libyuv.h"
+
+namespace openh264 {
+
+static const unsigned short kVideoWidth = 320;
+static const unsigned short kVideoHeight = 240;
+
+static const size_t kNumSampleFrames = 10;
+
+class OpenH264Tests : public testing::Test {
+ protected:
+  OpenH264Tests() {
+    int shade = 0;
+    for (size_t i = 0; i < kNumSampleFrames; ++i) {
+      CreateRgbFrame(&sample_frames_[i], kVideoWidth, kVideoHeight,
+                     shade, shade, shade);
+      shade += 255 / kNumSampleFrames;
+    }
+  }
+  ~OpenH264Tests() override {}
+
+  VideoFrame sample_frames_[kNumSampleFrames];
+  H264CodecTester codec_tester_;
+};
+
+TEST_F(OpenH264Tests, EncodeDecodeCompareFrames) {
+  const int kNumFrames = 30;
+
+  ASSERT_TRUE(codec_tester_.Init(kVideoWidth, kVideoHeight));
+  double avg_ssim = 0.0;
+  for (size_t i = 0; i < kNumFrames; ++i) {
+    VideoFrame* original_frame = &sample_frames_[i % kNumSampleFrames];
+    ASSERT_TRUE(codec_tester_.Encode(*original_frame));
+    VideoFrame* decoded_frame = codec_tester_.Decode();
+    ASSERT_TRUE(decoded_frame != nullptr);
+
+    avg_ssim += webrtc::I420SSIM(original_frame, decoded_frame);
+  }
+  avg_ssim /= kNumFrames;
+
+  ASSERT_GE(avg_ssim, 0.9) << "Expected decoded frames to be more similar (on "
+                           << "average) to the original frames (SSIM too low)";
+}

[hbos_chromium, 2015/10/29 14:28:26]

Note: I want to have another test that measures the enc/dec performance for
future comparison when we build with architecture-specific assembly code. I'm
not sure what type of test that is though.

+
+#if defined(OS_CHROMEOS)

[hbos_chromium, 2015/10/29 14:28:26]

Note: This #if is to make only a small number of trybots turn red to make it
easier to see if it is otherwise green or not. We only need one to turn red to
stop us from accidentally landing a CL with default build_openh264==1.
I should add a comment about this and also add another define like
DISABLE_BUILDINGWITHOPENH264SHOULDFAIL (mmm, long names) so that it is possible
to turn build_openh264==1 e.g. for Chrome without turning red.

+TEST_F(OpenH264Tests, BuildingWithOpenH264ShouldFail) {
+  FAIL() << "Building with 'build_openh264==1' / defined(BUILD_OPENH264) makes "
+            "this test fail. This is to ensure you do not accidentally land a "
+            "CL that changes the default behavior. The default should be not "
+            "to build it in Chromium due to licensing issues! However, you may "
+            "have to temporarily change the default behavior in order for the "
+            "trybots to run the OpenH264Tests test code.";
+}
+#endif
+
+}  // namespace openh264