Add AudioEncoder::GetTargetBitrate

webrtc/modules/audio_coding/codecs/opus/audio_encoder_mutable_opus_test.cc

 /*
  *  Copyright (c) 2015 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 61 matching lines @@
 
 TEST_F(AudioEncoderMutableOpusTest, ToggleDtx) {
   CreateCodec(2);
   // Enable DTX
   EXPECT_TRUE(encoder_->SetDtx(true));
   // Verify that the mode is still kAudio.
   EXPECT_EQ(AudioEncoderOpus::kAudio, encoder_->application());
   // Turn off DTX.
   EXPECT_TRUE(encoder_->SetDtx(false));
 }
+
+TEST_F(AudioEncoderMutableOpusTest, SetBitrate) {
+  CreateCodec(1);
+  // Constants are replicated from audio_encoder_opus.cc.
+  const int kMinBitrateBps = 500;
+  const int kMaxBitrateBps = 512000;
+  // Set a too low bitrate.
+  encoder_->SetTargetBitrate(kMinBitrateBps - 1);
+  EXPECT_EQ(kMinBitrateBps, encoder_->GetTargetBitrate());
+  // Set a too high bitrate.
+  encoder_->SetTargetBitrate(kMaxBitrateBps + 1);
+  EXPECT_EQ(kMaxBitrateBps, encoder_->GetTargetBitrate());
+  // Set the minimum rate.
+  encoder_->SetTargetBitrate(kMinBitrateBps);
+  EXPECT_EQ(kMinBitrateBps, encoder_->GetTargetBitrate());
+  // Set the maximum rate.
+  encoder_->SetTargetBitrate(kMaxBitrateBps);
+  EXPECT_EQ(kMaxBitrateBps, encoder_->GetTargetBitrate());
+  // Set rates from 1000 up to 32000 bps.
+  for (int rate = 1000; rate <= 32000; rate += 1000) {
+    encoder_->SetTargetBitrate(rate);
+    EXPECT_EQ(rate, encoder_->GetTargetBitrate());
+  }
+}
 #endif  // WEBRTC_CODEC_OPUS
 
 }  // namespace acm2
 }  // namespace webrtc