Update RateStatistics to handle too-little-data case.

webrtc/modules/remote_bitrate_estimator/remote_bitrate_estimator_unittest_helper.cc

 /*
  *  Copyright (c) 2012 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/remote_bitrate_estimator/remote_bitrate_estimator_unittest_helper.h"
 
 #include <algorithm>
 #include <limits>
 #include <utility>
 
 namespace webrtc {
 
 const size_t kMtu = 1200;
 const uint32_t kAcceptedBitrateErrorBps = 50000;
 
+// Number of packets needed before we have a valid estimate.
+const int kNumInitialPackets = 2;
+
 namespace testing {
 
 void TestBitrateObserver::OnReceiveBitrateChanged(
     const std::vector<uint32_t>& ssrcs,
     uint32_t bitrate) {
   latest_bitrate_ = bitrate;
   updated_ = true;
 }
 
 RtpStream::RtpStream(int fps,
@@ skipping 279 matching lines @@
   uint32_t absolute_send_time = 0;
   std::vector<uint32_t> ssrcs;
   EXPECT_FALSE(bitrate_estimator_->LatestEstimate(&ssrcs, &bitrate_bps));
   EXPECT_EQ(0u, ssrcs.size());
   clock_.AdvanceTimeMilliseconds(1000);
   bitrate_estimator_->Process();
   EXPECT_FALSE(bitrate_estimator_->LatestEstimate(&ssrcs, &bitrate_bps));
   EXPECT_FALSE(bitrate_observer_->updated());
   bitrate_observer_->Reset();
   clock_.AdvanceTimeMilliseconds(1000);
-  // Inserting a packet. Still no valid estimate. We need to wait 5 seconds.
-  IncomingPacket(kDefaultSsrc, kMtu, clock_.TimeInMilliseconds(), timestamp,
-                 absolute_send_time, true);
-  bitrate_estimator_->Process();
-  EXPECT_FALSE(bitrate_estimator_->LatestEstimate(&ssrcs, &bitrate_bps));
-  EXPECT_EQ(0u, ssrcs.size());
-  EXPECT_FALSE(bitrate_observer_->updated());
-  bitrate_observer_->Reset();
   // Inserting packets for 5 seconds to get a valid estimate.
-  for (int i = 0; i < 5 * kFramerate + 1; ++i) {
+  for (int i = 0; i < 5 * kFramerate + 1 + kNumInitialPackets; ++i) {
+    if (i == kNumInitialPackets) {
+      bitrate_estimator_->Process();
+      EXPECT_FALSE(bitrate_estimator_->LatestEstimate(&ssrcs, &bitrate_bps));
+      EXPECT_EQ(0u, ssrcs.size());
+      EXPECT_FALSE(bitrate_observer_->updated());
+      bitrate_observer_->Reset();
+    }
+
     IncomingPacket(kDefaultSsrc, kMtu, clock_.TimeInMilliseconds(), timestamp,
                    absolute_send_time, true);
     clock_.AdvanceTimeMilliseconds(1000 / kFramerate);
     timestamp += 90 * kFrameIntervalMs;
     absolute_send_time = AddAbsSendTime(absolute_send_time,
                                         kFrameIntervalAbsSendTime);
   }
   bitrate_estimator_->Process();
   EXPECT_TRUE(bitrate_estimator_->LatestEstimate(&ssrcs, &bitrate_bps));
   ASSERT_EQ(1u, ssrcs.size());
   EXPECT_EQ(kDefaultSsrc, ssrcs.front());
   EXPECT_NEAR(expected_converge_bitrate, bitrate_bps, kAcceptedBitrateErrorBps);
   EXPECT_TRUE(bitrate_observer_->updated());
   bitrate_observer_->Reset();
   EXPECT_EQ(bitrate_observer_->latest_bitrate(), bitrate_bps);
   bitrate_estimator_->RemoveStream(kDefaultSsrc);
   EXPECT_TRUE(bitrate_estimator_->LatestEstimate(&ssrcs, &bitrate_bps));
   ASSERT_EQ(0u, ssrcs.size());
   EXPECT_EQ(0u, bitrate_bps);
 }
 
 void RemoteBitrateEstimatorTest::RateIncreaseReorderingTestHelper(
     uint32_t expected_bitrate_bps) {
   const int kFramerate = 50;  // 50 fps to avoid rounding errors.
   const int kFrameIntervalMs = 1000 / kFramerate;
   const uint32_t kFrameIntervalAbsSendTime = AbsSendTime(1, kFramerate);
   uint32_t timestamp = 0;
   uint32_t absolute_send_time = 0;
-  IncomingPacket(kDefaultSsrc, 1000, clock_.TimeInMilliseconds(), timestamp,
-                 absolute_send_time, true);
-  bitrate_estimator_->Process();
-  EXPECT_FALSE(bitrate_observer_->updated());  // No valid estimate.
-  // Inserting packets for one second to get a valid estimate.
-  for (int i = 0; i < 5 * kFramerate + 1; ++i) {
+  // Inserting packets for five seconds to get a valid estimate.
+  for (int i = 0; i < 5 * kFramerate + 1 + kNumInitialPackets; ++i) {
+    // TODO(sprang): Remove this hack once the single stream estimator is gone,
+    // as it doesn't do anything in Process().
+    if (i == kNumInitialPackets) {
+      // Process after we have enough frames to get a valid input rate estimate.
+      bitrate_estimator_->Process();
+      EXPECT_FALSE(bitrate_observer_->updated());  // No valid estimate.
+    }
+
     IncomingPacket(kDefaultSsrc, kMtu, clock_.TimeInMilliseconds(), timestamp,
                    absolute_send_time, true);
     clock_.AdvanceTimeMilliseconds(kFrameIntervalMs);
     timestamp += 90 * kFrameIntervalMs;
     absolute_send_time = AddAbsSendTime(absolute_send_time,
                                         kFrameIntervalAbsSendTime);
   }
   bitrate_estimator_->Process();
   EXPECT_TRUE(bitrate_observer_->updated());
   EXPECT_NEAR(expected_bitrate_bps,
@@ skipping 216 matching lines @@
     clock_.AdvanceTimeMilliseconds(2 * kFrameIntervalMs);
     absolute_send_time = AddAbsSendTime(absolute_send_time,
                                         kFrameIntervalAbsSendTime);
     bitrate_estimator_->Process();
   }
   uint32_t bitrate_after = 0;
   bitrate_estimator_->LatestEstimate(&ssrcs, &bitrate_after);
   EXPECT_LT(bitrate_after, bitrate_before);
 }
 }  // namespace webrtc