Utilize bitrate above codec max to protect video.

webrtc/modules/video_coding/main/source/media_optimization_unittest.cc

 /*
  *  Copyright (c) 2013 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.
  */
 
@@ skipping 47 matching lines @@
   // above 50 + 10 kbps again.
   const uint32_t kThresholdBps = 50000;
   const uint32_t kWindowBps = 10000;
   media_opt_.SuspendBelowMinBitrate(kThresholdBps, kWindowBps);
 
   // The video should not be suspended from the start.
   EXPECT_FALSE(media_opt_.IsVideoSuspended());
 
   uint32_t target_bitrate_kbps = 100;
   media_opt_.SetTargetRates(target_bitrate_kbps * 1000,
-                            0,  // Lossrate.
-                            100,
-                            NULL,
-                            NULL);  // RTT in ms.
+                            0,    // Lossrate.
+                            100,  // RTT in ms.
+                            nullptr, nullptr);
   media_opt_.EnableFrameDropper(true);
   for (int time = 0; time < 2000; time += frame_time_ms_) {
     ASSERT_NO_FATAL_FAILURE(AddFrameAndAdvanceTime(target_bitrate_kbps, false));
   }
 
   // Set the target rate below the limit for muting.
   media_opt_.SetTargetRates(kThresholdBps - 1000,
-                            0,  // Lossrate.
-                            100,
-                            NULL,
-                            NULL);  // RTT in ms.
+                            0,    // Lossrate.
+                            100,  // RTT in ms.
+                            nullptr, nullptr);
   // Expect the muter to engage immediately and stay muted.
   // Test during 2 seconds.
   for (int time = 0; time < 2000; time += frame_time_ms_) {
     EXPECT_TRUE(media_opt_.IsVideoSuspended());
     ASSERT_NO_FATAL_FAILURE(AddFrameAndAdvanceTime(target_bitrate_kbps, true));
   }
 
   // Set the target above the limit for muting, but not above the
   // limit + window.
   media_opt_.SetTargetRates(kThresholdBps + 1000,
-                            0,  // Lossrate.
-                            100,
-                            NULL,
-                            NULL);  // RTT in ms.
-                                    // Expect the muter to stay muted.
+                            0,    // Lossrate.
+                            100,  // RTT in ms.
+                            nullptr, nullptr);
+  // Expect the muter to stay muted.
   // Test during 2 seconds.
   for (int time = 0; time < 2000; time += frame_time_ms_) {
     EXPECT_TRUE(media_opt_.IsVideoSuspended());
     ASSERT_NO_FATAL_FAILURE(AddFrameAndAdvanceTime(target_bitrate_kbps, true));
   }
 
   // Set the target above limit + window.
   media_opt_.SetTargetRates(kThresholdBps + kWindowBps + 1000,
-                            0,  // Lossrate.
-                            100,
-                            NULL,
-                            NULL);  // RTT in ms.
+                            0,    // Lossrate.
+                            100,  // RTT in ms.
+                            nullptr, nullptr);
   // Expect the muter to disengage immediately.
   // Test during 2 seconds.
   for (int time = 0; time < 2000; time += frame_time_ms_) {
     EXPECT_FALSE(media_opt_.IsVideoSuspended());
     ASSERT_NO_FATAL_FAILURE(
         AddFrameAndAdvanceTime((kThresholdBps + kWindowBps) / 1000, false));
   }
 }
 
+TEST_F(TestMediaOptimization, ProtectsUsingFecBitrateAboveCodecMax) {
+  static const int kCodecBitrateBps = 100000;
+  static const int kMaxBitrateBps = 130000;
+
+  class ProtectionCallback : public VCMProtectionCallback {
+    int ProtectionRequest(const FecProtectionParams* delta_params,
+                          const FecProtectionParams* key_params,
+                          uint32_t* sent_video_rate_bps,
+                          uint32_t* sent_nack_rate_bps,
+                          uint32_t* sent_fec_rate_bps) override {
+      *sent_video_rate_bps = kCodecBitrateBps;
+      *sent_nack_rate_bps = 0;
+      *sent_fec_rate_bps = fec_rate_bps_;
+      return 0;
+    }
+
+   public:
+    uint32_t fec_rate_bps_;
+  } protection_callback;
+
+  media_opt_.SetProtectionMethod(kFec);
+  media_opt_.SetEncodingData(kVideoCodecVP8, kCodecBitrateBps, kCodecBitrateBps,
+                             640, 480, 30, 1, 1000);
+
+  // Using 10% of codec bitrate for FEC, should still be able to use all of it.
+  protection_callback.fec_rate_bps_ = kCodecBitrateBps / 10;
+  uint32_t target_bitrate = media_opt_.SetTargetRates(
+      kMaxBitrateBps, 0, 0, &protection_callback, nullptr);
+
+  EXPECT_EQ(kCodecBitrateBps, static_cast<int>(target_bitrate));
+
+  // Using as much for codec bitrate as fec rate, new target rate should share
+  // both equally, but only be half of max (since that ceiling should be hit).
+  protection_callback.fec_rate_bps_ = kCodecBitrateBps;
+  target_bitrate = media_opt_.SetTargetRates(kMaxBitrateBps, 128, 100,
+                                             &protection_callback, nullptr);
+  EXPECT_EQ(kMaxBitrateBps / 2, static_cast<int>(target_bitrate));
+}
+
 }  // namespace media_optimization
 }  // namespace webrtc