Fix channel layout reporting for implicit signalling of AAC parametric stereo

media/mp4/aac_unittest.cc

 // Copyright (c) 2012 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 "media/mp4/aac.h"
 
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace media {
 
 namespace mp4 {
 
 TEST(AACTest, BasicProfileTest) {
   AAC aac;
   uint8 buffer[] = {0x12, 0x10};
   std::vector<uint8> data;
 
   data.assign(buffer, buffer + sizeof(buffer));
 
   EXPECT_TRUE(aac.Parse(data));
   EXPECT_EQ(aac.GetOutputSamplesPerSecond(false), 44100);
-  EXPECT_EQ(aac.channel_layout(), CHANNEL_LAYOUT_STEREO);
+  EXPECT_EQ(aac.GetChannelLayout(false), CHANNEL_LAYOUT_STEREO);
 }
 
 TEST(AACTest, ExtensionTest) {
   AAC aac;
   uint8 buffer[] = {0x13, 0x08, 0x56, 0xe5, 0x9d, 0x48, 0x80};
   std::vector<uint8> data;
 
   data.assign(buffer, buffer + sizeof(buffer));
 
   EXPECT_TRUE(aac.Parse(data));
   EXPECT_EQ(aac.GetOutputSamplesPerSecond(false), 48000);
   EXPECT_EQ(aac.GetOutputSamplesPerSecond(true), 48000);
-  EXPECT_EQ(aac.channel_layout(), CHANNEL_LAYOUT_STEREO);
+  EXPECT_EQ(aac.GetChannelLayout(false), CHANNEL_LAYOUT_STEREO);
 }
 
-TEST(AACTest, TestImplicitSBR) {
+// Test implicit SBR with mono channel config.
+// Mono channel layout should only be reported if SBR is not
+// specified. Otherwise stereo should be reported.
+// See ISO-14496-3 Section 1.6.6.1.2 for details about this special casing.
+TEST(AACTest, TestImplicitSBR_ChannelConfig0) {
+  AAC aac;
+  uint8 buffer[] = {0x13, 0x08};
+  std::vector<uint8> data;
+
+  data.assign(buffer, buffer + sizeof(buffer));
+
+  EXPECT_TRUE(aac.Parse(data));
+
+  // Test w/o implict SBR.
+  EXPECT_EQ(aac.GetOutputSamplesPerSecond(false), 24000);
+  EXPECT_EQ(aac.GetChannelLayout(false), CHANNEL_LAYOUT_MONO);
+
+  // Test implicit SBR.
+  EXPECT_EQ(aac.GetOutputSamplesPerSecond(true), 48000);
+  EXPECT_EQ(aac.GetChannelLayout(true), CHANNEL_LAYOUT_STEREO);
+}
+
+// Tests implicit SBR with a stereo channel config.
+TEST(AACTest, TestImplicitSBR_ChannelConfig1) {
   AAC aac;
   uint8 buffer[] = {0x13, 0x10};
   std::vector<uint8> data;
 
   data.assign(buffer, buffer + sizeof(buffer));
 
   EXPECT_TRUE(aac.Parse(data));
+
+  // Test w/o implict SBR.
   EXPECT_EQ(aac.GetOutputSamplesPerSecond(false), 24000);
+  EXPECT_EQ(aac.GetChannelLayout(false), CHANNEL_LAYOUT_STEREO);
+
+  // Test implicit SBR.
   EXPECT_EQ(aac.GetOutputSamplesPerSecond(true), 48000);
-  EXPECT_EQ(aac.channel_layout(), CHANNEL_LAYOUT_STEREO);
+  EXPECT_EQ(aac.GetChannelLayout(true), CHANNEL_LAYOUT_STEREO);
 }
 
 TEST(AACTest, SixChannelTest) {
   AAC aac;
   uint8 buffer[] = {0x11, 0xb0};
   std::vector<uint8> data;
 
   data.assign(buffer, buffer + sizeof(buffer));
 
   EXPECT_TRUE(aac.Parse(data));
   EXPECT_EQ(aac.GetOutputSamplesPerSecond(false), 48000);
-  EXPECT_EQ(aac.channel_layout(), CHANNEL_LAYOUT_5_1);
+  EXPECT_EQ(aac.GetChannelLayout(false), CHANNEL_LAYOUT_5_1);
 }
 
 TEST(AACTest, DataTooShortTest) {
   AAC aac;
   std::vector<uint8> data;
 
   EXPECT_FALSE(aac.Parse(data));
 
   data.push_back(0x12);
   EXPECT_FALSE(aac.Parse(data));
@@ skipping 38 matching lines @@
 
   EXPECT_FALSE(aac.Parse(data));
 
   data[1] = 0x08;
   EXPECT_TRUE(aac.Parse(data));
 }
 
 }  // namespace mp4
 
 }  // namespace media