Implement a high-QP threshold for Android H.264.

webrtc/modules/video_coding/utility/quality_scaler_unittest.cc

 /*
  *  Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
 #include "webrtc/modules/video_coding/utility/include/quality_scaler.h"
 
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace webrtc {
 namespace {
 static const int kNumSeconds = 10;
 static const int kWidth = 1920;
 static const int kHalfWidth = kWidth / 2;
 static const int kHeight = 1080;
 static const int kFramerate = 30;
 static const int kLowQp = 15;
 static const int kNormalQp = 30;
+static const int kHighQp = 40;
 static const int kMaxQp = 56;
 }  // namespace
 
 class QualityScalerTest : public ::testing::Test {
  public:
   // Temporal and spatial resolution.
   struct Resolution {
     int framerate;
     int width;
     int height;
   };
  protected:
-  enum ScaleDirection { kScaleDown, kScaleUp };
+  enum ScaleDirection {
+    kKeepScaleAtHighQp,
+    kScaleDown,
+    kScaleDownAboveHighQp,
+    kScaleUp
+  };
   enum BadQualityMetric { kDropFrame, kReportLowQP };
 
   QualityScalerTest() {
     input_frame_.CreateEmptyFrame(
         kWidth, kHeight, kWidth, kHalfWidth, kHalfWidth);
-    qs_.Init(kMaxQp / QualityScaler::kDefaultLowQpDenominator, false);
+    qs_.Init(kMaxQp / QualityScaler::kDefaultLowQpDenominator, kHighQp, false);
     qs_.ReportFramerate(kFramerate);
     qs_.OnEncodeFrame(input_frame_);
   }
 
   bool TriggerScale(ScaleDirection scale_direction) {
     qs_.OnEncodeFrame(input_frame_);
     int initial_width = qs_.GetScaledResolution().width;
     for (int i = 0; i < kFramerate * kNumSeconds; ++i) {
       switch (scale_direction) {
         case kScaleUp:
           qs_.ReportQP(kLowQp);
           break;
         case kScaleDown:
           qs_.ReportDroppedFrame();
           break;
+        case kKeepScaleAtHighQp:
+          qs_.ReportQP(kHighQp);
+          break;
+        case kScaleDownAboveHighQp:
+          qs_.ReportQP(kHighQp + 1);
+          break;
       }
       qs_.OnEncodeFrame(input_frame_);
       if (qs_.GetScaledResolution().width != initial_width)
         return true;
     }
 
     return false;
   }
 
   void ExpectOriginalFrame() {
@@ skipping 42 matching lines @@
 }
 
 TEST_F(QualityScalerTest, DownscalesAfterContinuousFramedrop) {
   EXPECT_TRUE(TriggerScale(kScaleDown)) << "No downscale within " << kNumSeconds
                                         << " seconds.";
   QualityScaler::Resolution res = qs_.GetScaledResolution();
   EXPECT_LT(res.width, input_frame_.width());
   EXPECT_LT(res.height, input_frame_.height());
 }
 
+TEST_F(QualityScalerTest, KeepsScaleAtHighQp) {
+  EXPECT_FALSE(TriggerScale(kKeepScaleAtHighQp))
+      << "Downscale at high threshold which should keep scale.";
+  QualityScaler::Resolution res = qs_.GetScaledResolution();
+  EXPECT_EQ(res.width, input_frame_.width());
+  EXPECT_EQ(res.height, input_frame_.height());
+}
+
+TEST_F(QualityScalerTest, DownscalesAboveHighQp) {
+  EXPECT_TRUE(TriggerScale(kScaleDownAboveHighQp))
+      << "No downscale within " << kNumSeconds << " seconds.";
+  QualityScaler::Resolution res = qs_.GetScaledResolution();
+  EXPECT_LT(res.width, input_frame_.width());
+  EXPECT_LT(res.height, input_frame_.height());
+}
+
 TEST_F(QualityScalerTest, DownscalesAfterTwoThirdsFramedrop) {
   for (int i = 0; i < kFramerate * kNumSeconds / 3; ++i) {
     qs_.ReportQP(kNormalQp);
     qs_.ReportDroppedFrame();
     qs_.ReportDroppedFrame();
     qs_.OnEncodeFrame(input_frame_);
     if (qs_.GetScaledResolution().width < input_frame_.width())
       return;
   }
 
@@ skipping 125 matching lines @@
       qs_.ReportFramerate(res.framerate);
     res.width = qs_.GetScaledResolution().width;
     res.height = qs_.GetScaledResolution().height;
   }
   return res;
 }
 
 void QualityScalerTest::VerifyQualityAdaptation(
     int initial_framerate, int seconds, bool expect_spatial_resize,
     bool expect_framerate_reduction) {
-  qs_.Init(kMaxQp / QualityScaler::kDefaultLowQpDenominator, true);
+  const int kDisabledBadQpThreshold = kMaxQp + 1;
+  qs_.Init(kMaxQp / QualityScaler::kDefaultLowQpDenominator,
+           kDisabledBadQpThreshold, true);
   qs_.OnEncodeFrame(input_frame_);
   int init_width = qs_.GetScaledResolution().width;
   int init_height = qs_.GetScaledResolution().height;
 
   // Test reducing framerate by dropping frame continuously.
   QualityScalerTest::Resolution res = TriggerResolutionChange(
       kDropFrame, seconds, initial_framerate);
 
   if (expect_framerate_reduction) {
     EXPECT_LT(res.framerate, initial_framerate);
@@ skipping 104 matching lines @@
   DownscaleEndsAt(1600, 800, 200, 100);
 }
 
 TEST_F(QualityScalerTest, RespectsMinResolutionHeight) {
   // Should end at 100x200, as height can't go lower.
   qs_.SetMinResolution(10, 200);
   DownscaleEndsAt(800, 1600, 100, 200);
 }
 
 }  // namespace webrtc