Implement all resolution change policies for desktop and tab capture.

content/browser/media/capture/capture_resolution_evaluator_unittest.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 "content/browser/media/capture/capture_resolution_evaluator.h"
+
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace content {
+
+namespace {
+

[Wez, 2015/05/13 19:05:09]

nit: Don't think you need an empty namespace since const into will implicitly
have static linkage, below?

[miu, 2015/05/14 01:21:32]

I don't want to export these symbols.  I could remove the anonymous namespace
and add the static keyword, but that's just a matter of taste.  ;-)

[Wez, 2015/05/15 00:55:42]

My point is that you neither need the namespace nor the static keyword - const
variables at global scope are implicitly static, AFAIK.

[miu, 2015/05/15 21:14:00]

They are static, but the symbol is public in the compilation unit.  Meaning,
there would be a content::kMaxFrameWidth, etc. that other compilation units may
erroneously reference and this would unexpectedly resolve at link time without
error.  Instead, if other modules declare but do not define kMaxFrameWidth, it
should result in a linker error.

Said another way, my intention is that kMaxFrameWidth and friends should not be
visible/accessible outside of this module.

[Wez, 2015/05/15 23:31:31]

Yes, I understand that - if they were _global_ consts then AFAIK they should be
implicitly static, i.e. not visible outside this module - they're only visible
w/out the anon namespace because they're not global, but appear inside the
content namespace.

+// 16:9 maximum and minimum frame sizes.
+const int kMaxFrameWidth = 3840;
+const int kMaxFrameHeight = 2160;
+const int kMinFrameWidth = 320;
+const int kMinFrameHeight = 180;
+
+}  // namespace
+
+TEST(CaptureResolutionEvaluatorTest,
+     FixedResolutionPolicy_CaptureSizeAlwaysFixed) {

[Wez, 2015/05/13 19:05:09]

nit: Suggest putting a blank line between each call+expectation pair, so this
reads more clearly as a sequence of updates & checks.

[miu, 2015/05/14 01:21:32]

Done.

+  const gfx::Size the_one_frame_size(kMaxFrameWidth, kMaxFrameHeight);
+  CaptureResolutionEvaluator evaluator(
+      the_one_frame_size,
+      media::RESOLUTION_POLICY_FIXED_RESOLUTION);
+  EXPECT_EQ(the_one_frame_size, evaluator.capture_size());
+  evaluator.UpdateForNewSourceSize(the_one_frame_size);
+  EXPECT_EQ(the_one_frame_size, evaluator.capture_size());
+  evaluator.UpdateForNewSourceSize(gfx::Size(kMaxFrameWidth + 424,
+                                             kMaxFrameHeight - 101));
+  EXPECT_EQ(the_one_frame_size, evaluator.capture_size());
+  evaluator.UpdateForNewSourceSize(gfx::Size(kMaxFrameWidth - 202,
+                                             kMaxFrameHeight + 56));
+  EXPECT_EQ(the_one_frame_size, evaluator.capture_size());
+  evaluator.UpdateForNewSourceSize(gfx::Size(kMinFrameWidth, kMinFrameHeight));
+  EXPECT_EQ(the_one_frame_size, evaluator.capture_size());
+}
+
+TEST(CaptureResolutionEvaluatorTest,
+     FixedAspectRatioPolicy_CaptureSizeHasSameAspectRatio) {
+  CaptureResolutionEvaluator evaluator(
+      gfx::Size(kMaxFrameWidth, kMaxFrameHeight),
+      media::RESOLUTION_POLICY_FIXED_ASPECT_RATIO);
+
+#define EXPECT_IS_WITHIN_BOUNDS_AND_SAME_ASPECT_RATIO()               \

[Wez, 2015/05/13 19:05:09]

Might be cleaner to take the hit of parameterizing this on a Size and making it
global to this code file, so you don't need to undefined it, below?

[miu, 2015/05/14 01:21:32]

Done.

+  ASSERT_LE(kMinFrameWidth, evaluator.capture_size().width());        \
+  ASSERT_LE(kMinFrameHeight, evaluator.capture_size().height());      \
+  EXPECT_GE(kMaxFrameWidth, evaluator.capture_size().width());        \
+  EXPECT_GE(kMaxFrameHeight, evaluator.capture_size().height());      \
+  EXPECT_NEAR(static_cast<double>(kMaxFrameWidth) / kMaxFrameHeight,  \
+              static_cast<double>(evaluator.capture_size().width()) / \
+                  evaluator.capture_size().height(),                  \
+              0.01)
+
+  // Starting condition.
+  EXPECT_IS_WITHIN_BOUNDS_AND_SAME_ASPECT_RATIO();
+
+  // Max size in --> max size out.
+  evaluator.UpdateForNewSourceSize(gfx::Size(kMaxFrameWidth, kMaxFrameHeight));
+  EXPECT_IS_WITHIN_BOUNDS_AND_SAME_ASPECT_RATIO();
+
+  // Various source sizes within bounds.
+  evaluator.UpdateForNewSourceSize(gfx::Size(640, 480));
+  EXPECT_IS_WITHIN_BOUNDS_AND_SAME_ASPECT_RATIO();
+  evaluator.UpdateForNewSourceSize(gfx::Size(480, 640));
+  EXPECT_IS_WITHIN_BOUNDS_AND_SAME_ASPECT_RATIO();
+  evaluator.UpdateForNewSourceSize(gfx::Size(640, 640));
+  EXPECT_IS_WITHIN_BOUNDS_AND_SAME_ASPECT_RATIO();
+  const gfx::Size unchanged_size = evaluator.capture_size();

[Wez, 2015/05/13 19:05:09]

Looks like this belongs in the next block?

[miu, 2015/05/14 01:21:33]

Done.

+
+  // Bad source size results in no update.
+  evaluator.UpdateForNewSourceSize(gfx::Size(0, 0));
+  EXPECT_EQ(unchanged_size, evaluator.capture_size());
+
+  // Downscaling size (preserving aspect ratio) when source size exceeds the
+  // upper bounds.
+  evaluator.UpdateForNewSourceSize(
+      gfx::Size(kMaxFrameWidth * 2, kMaxFrameHeight * 2));
+  EXPECT_IS_WITHIN_BOUNDS_AND_SAME_ASPECT_RATIO();
+  evaluator.UpdateForNewSourceSize(
+      gfx::Size(kMaxFrameWidth * 2, kMaxFrameHeight));
+  EXPECT_IS_WITHIN_BOUNDS_AND_SAME_ASPECT_RATIO();
+  evaluator.UpdateForNewSourceSize(
+      gfx::Size(kMaxFrameWidth, kMaxFrameHeight * 2));
+  EXPECT_IS_WITHIN_BOUNDS_AND_SAME_ASPECT_RATIO();
+
+  // Upscaling size (preserving aspect ratio) when source size is under the
+  // lower bounds.
+  evaluator.UpdateForNewSourceSize(
+      gfx::Size(kMinFrameWidth / 2, kMinFrameHeight / 2));
+  EXPECT_IS_WITHIN_BOUNDS_AND_SAME_ASPECT_RATIO();
+  evaluator.UpdateForNewSourceSize(
+      gfx::Size(kMinFrameWidth / 2, kMaxFrameHeight));
+  EXPECT_IS_WITHIN_BOUNDS_AND_SAME_ASPECT_RATIO();
+  evaluator.UpdateForNewSourceSize(
+      gfx::Size(kMinFrameWidth, kMinFrameHeight / 2));
+  EXPECT_IS_WITHIN_BOUNDS_AND_SAME_ASPECT_RATIO();
+
+#undef EXPECT_IS_WITHIN_BOUNDS_AND_SAME_ASPECT_RATIO
+}
+
+TEST(CaptureResolutionEvaluatorTest,
+     AnyWithinLimitPolicy_CaptureSizeIsAnythingWithinLimits) {
+  const gfx::Size max_size(kMaxFrameWidth, kMaxFrameHeight);
+  CaptureResolutionEvaluator evaluator(
+      max_size, media::RESOLUTION_POLICY_ANY_WITHIN_LIMIT);
+
+  // Starting condition.
+  EXPECT_EQ(max_size, evaluator.capture_size());
+
+  // Max size in --> max size out.
+  evaluator.UpdateForNewSourceSize(max_size);
+  EXPECT_EQ(max_size, evaluator.capture_size());
+
+  // Various source sizes within bounds.
+  evaluator.UpdateForNewSourceSize(gfx::Size(640, 480));
+  EXPECT_EQ(gfx::Size(640, 480), evaluator.capture_size());
+  evaluator.UpdateForNewSourceSize(gfx::Size(480, 640));
+  EXPECT_EQ(gfx::Size(480, 640), evaluator.capture_size());
+  evaluator.UpdateForNewSourceSize(gfx::Size(640, 640));
+  EXPECT_EQ(gfx::Size(640, 640), evaluator.capture_size());
+  evaluator.UpdateForNewSourceSize(gfx::Size(2, 2));
+  EXPECT_EQ(gfx::Size(2, 2), evaluator.capture_size());
+  const gfx::Size unchanged_size = evaluator.capture_size();

[Wez, 2015/05/13 19:05:09]

As above

[miu, 2015/05/14 01:21:33]

Done.

+
+  // Bad source size results in no update.
+  evaluator.UpdateForNewSourceSize(gfx::Size(0, 0));
+  EXPECT_EQ(unchanged_size, evaluator.capture_size());
+
+  // Downscaling size (preserving aspect ratio) when source size exceeds the
+  // upper bounds.
+  evaluator.UpdateForNewSourceSize(
+      gfx::Size(kMaxFrameWidth * 2, kMaxFrameHeight * 2));
+  EXPECT_EQ(max_size, evaluator.capture_size());
+  evaluator.UpdateForNewSourceSize(
+      gfx::Size(kMaxFrameWidth * 2, kMaxFrameHeight));
+  EXPECT_EQ(gfx::Size(kMaxFrameWidth, kMaxFrameHeight / 2),
+            evaluator.capture_size());
+  evaluator.UpdateForNewSourceSize(
+      gfx::Size(kMaxFrameWidth, kMaxFrameHeight * 2));
+  EXPECT_EQ(gfx::Size(kMaxFrameWidth / 2, kMaxFrameHeight),
+            evaluator.capture_size());
+}
+
+}  // namespace content