diff --git a/RELEASENOTES.md b/RELEASENOTES.md
index 4e1520899c3..d3bd056860e 100644
--- a/RELEASENOTES.md
+++ b/RELEASENOTES.md
@@ -66,6 +66,7 @@
 *   Smooth Streaming Extension:
 *   RTSP Extension:
 *   Decoder Extensions (FFmpeg, VP9, AV1, MIDI, etc.):
+*   MIDI extension:
 *   Leanback extension:
 *   Cast Extension:
     *   Fix bug that converted the album title of the `MediaQueueItem` to the
diff --git a/constants.gradle b/constants.gradle
index f882ce2a877..b89c67ec813 100644
--- a/constants.gradle
+++ b/constants.gradle
@@ -12,7 +12,6 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 project.ext {
-<<<<<<< HEAD
     releaseVersion = '1.4.1'
     releaseVersionCode = 1_004_001_3_00
     minSdkVersion = 21
diff --git a/libraries/decoder_av1/build.gradle b/libraries/decoder_av1/build.gradle
index 6f66ad58801..b793cb2d8e7 100644
--- a/libraries/decoder_av1/build.gradle
+++ b/libraries/decoder_av1/build.gradle
@@ -27,6 +27,14 @@ android {
             }
         }
     }
+
+    // TODO(Internal: b/372449691): Remove packagingOptions once AGP is updated
+    // to version 8.5.1 or higher.
+    packagingOptions {
+        jniLibs {
+            useLegacyPackaging true
+        }
+    }
 }
 
 // Configure the native build only if libgav1 is present to avoid gradle sync
diff --git a/libraries/decoder_av1/src/main/jni/CMakeLists.txt b/libraries/decoder_av1/src/main/jni/CMakeLists.txt
index 0202f0af570..4a39b6cd38a 100644
--- a/libraries/decoder_av1/src/main/jni/CMakeLists.txt
+++ b/libraries/decoder_av1/src/main/jni/CMakeLists.txt
@@ -61,3 +61,7 @@ target_link_libraries(gav1JNI
                       PRIVATE libgav1_static
                       PRIVATE ${android_log_lib})
 
+# Enable 16 KB ELF alignment.
+target_link_options(gav1JNI
+                    PRIVATE "-Wl,-z,max-page-size=16384")
+
diff --git a/libraries/decoder_ffmpeg/build.gradle b/libraries/decoder_ffmpeg/build.gradle
index 524b63e9c5c..055c613cc02 100644
--- a/libraries/decoder_ffmpeg/build.gradle
+++ b/libraries/decoder_ffmpeg/build.gradle
@@ -19,6 +19,18 @@ android.externalNativeBuild.cmake.path = 'src/main/jni/CMakeLists.txt'
 // Should match cmake_minimum_required.
 android.externalNativeBuild.cmake.version = '3.21.0+'
 
+android {
+    namespace 'androidx.media3.decoder.ffmpeg'
+
+    // TODO(Internal: b/372449691): Remove packagingOptions once AGP is updated
+    // to version 8.5.1 or higher.
+    packagingOptions {
+        jniLibs {
+            useLegacyPackaging true
+        }
+    }
+}
+
 task assembleFfmpeg(type: Exec) {
     def host = ""
     if (Os.isFamily(Os.FAMILY_MAC)) {
diff --git a/libraries/decoder_ffmpeg/src/main/jni/CMakeLists.txt b/libraries/decoder_ffmpeg/src/main/jni/CMakeLists.txt
index fe74c78048d..819cb5baa41 100644
--- a/libraries/decoder_ffmpeg/src/main/jni/CMakeLists.txt
+++ b/libraries/decoder_ffmpeg/src/main/jni/CMakeLists.txt
@@ -56,3 +56,7 @@ target_link_libraries(ffmpegJNI
 if(ANDROID_ABI STREQUAL "arm64-v8a")
     target_link_options(ffmpegJNI PRIVATE "-Wl,-Bsymbolic")
 endif()
+
+# Enable 16 KB ELF alignment.
+target_link_options(ffmpegJNI
+                    PRIVATE "-Wl,-z,max-page-size=16384")
diff --git a/libraries/decoder_flac/build.gradle b/libraries/decoder_flac/build.gradle
index 0da6fa2e525..a7fa55ee409 100644
--- a/libraries/decoder_flac/build.gradle
+++ b/libraries/decoder_flac/build.gradle
@@ -23,6 +23,14 @@ android {
         }
         androidTest.assets.srcDir '../test_data/src/test/assets'
     }
+
+    // TODO(Internal: b/372449691): Remove packagingOptions once AGP is updated
+    // to version 8.5.1 or higher.
+    packagingOptions {
+        jniLibs {
+            useLegacyPackaging true
+        }
+    }
 }
 
 dependencies {
diff --git a/libraries/decoder_flac/src/main/jni/Android.mk b/libraries/decoder_flac/src/main/jni/Android.mk
index 69520a16e58..b19d169111c 100644
--- a/libraries/decoder_flac/src/main/jni/Android.mk
+++ b/libraries/decoder_flac/src/main/jni/Android.mk
@@ -35,4 +35,6 @@ LOCAL_CFLAGS += -D_REENTRANT -DPIC -DU_COMMON_IMPLEMENTATION -fPIC -DHAVE_SYS_PA
 LOCAL_CFLAGS += -O3 -funroll-loops -finline-functions -DFLAC__NO_ASM '-DFLAC__HAS_OGG=0'
 
 LOCAL_LDLIBS := -llog -lz -lm
+# Enable 16 KB ELF alignment.
+LOCAL_LDFLAGS += "-Wl,-z,max-page-size=16384"
 include $(BUILD_SHARED_LIBRARY)
diff --git a/libraries/decoder_iamf/build.gradle b/libraries/decoder_iamf/build.gradle
new file mode 100644
index 00000000000..17970629bc7
--- /dev/null
+++ b/libraries/decoder_iamf/build.gradle
@@ -0,0 +1,67 @@
+// Copyright 2024 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+apply from: "$gradle.ext.androidxMediaSettingsDir/common_library_config.gradle"
+
+android {
+    namespace 'androidx.media3.decoder.iamf'
+
+    sourceSets {
+        androidTest.assets.srcDir '../test_data/src/test/assets'
+    }
+
+    defaultConfig {
+        externalNativeBuild {
+            cmake {
+                targets "iamfJNI"
+            }
+        }
+    }
+
+    // TODO(Internal: b/372449691): Remove packagingOptions once AGP is updated
+    // to version 8.5.1 or higher.
+    packagingOptions {
+        jniLibs {
+            useLegacyPackaging true
+        }
+    }
+}
+
+// Configure the native build only if libiamf is present to avoid gradle sync
+// failures if libiamf hasn't been built according to the README instructions.
+if (project.file('src/main/jni/libiamf').exists()) {
+    android.externalNativeBuild.cmake {
+        path = 'src/main/jni/CMakeLists.txt'
+        version = '3.21.0+'
+        if (project.hasProperty('externalNativeBuildDir')) {
+            if (!new File(externalNativeBuildDir).isAbsolute()) {
+                ext.externalNativeBuildDir =
+                        new File(rootDir, it.externalNativeBuildDir)
+            }
+            buildStagingDirectory = "${externalNativeBuildDir}/${project.name}"
+        }
+    }
+}
+
+dependencies {
+    implementation project(modulePrefix + 'lib-decoder')
+    // TODO(b/203752526): Remove this dependency.
+    implementation project(modulePrefix + 'lib-exoplayer')
+    implementation 'androidx.annotation:annotation:' + androidxAnnotationVersion
+    compileOnly 'org.jetbrains.kotlin:kotlin-annotations-jvm:' + kotlinAnnotationsVersion
+    testImplementation project(modulePrefix + 'test-utils')
+    testImplementation 'org.robolectric:robolectric:' + robolectricVersion
+    androidTestImplementation project(modulePrefix + 'test-utils')
+    androidTestImplementation 'androidx.test:runner:' + androidxTestRunnerVersion
+    androidTestImplementation 'androidx.test.ext:junit:' + androidxTestJUnitVersion
+}
diff --git a/libraries/decoder_iamf/src/main/jni/CMakeLists.txt b/libraries/decoder_iamf/src/main/jni/CMakeLists.txt
new file mode 100644
index 00000000000..32a65ed1ac3
--- /dev/null
+++ b/libraries/decoder_iamf/src/main/jni/CMakeLists.txt
@@ -0,0 +1,50 @@
+#
+# Copyright 2024 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+cmake_minimum_required(VERSION 3.21.0 FATAL_ERROR)
+
+# Enable C++11 features.
+set(CMAKE_CXX_STANDARD 11)
+
+# Define project name for your JNI module
+project(libiamfJNI C CXX)
+
+set(libiamf_jni_root "${CMAKE_CURRENT_SOURCE_DIR}")
+
+# Build libiamf.
+add_subdirectory("${libiamf_jni_root}/libiamf/code"
+                 EXCLUDE_FROM_ALL)
+
+# Add the include directory from libiamf.
+include_directories ("${libiamf_jni_root}/libiamf/code/include")
+
+# Build libiamfJNI.
+add_library(iamfJNI
+            SHARED
+            iamf_jni.cc)
+
+# Locate NDK log library.
+find_library(android_log_lib log)
+
+# Link libgav1JNI against used libraries.
+target_link_libraries(iamfJNI
+                      PRIVATE android
+                      PRIVATE iamf
+                      PRIVATE ${android_log_lib})
+
+# Enable 16 KB ELF alignment.
+target_link_options(iamfJNI
+                    PRIVATE "-Wl,-z,max-page-size=16384")
diff --git a/libraries/decoder_opus/build.gradle b/libraries/decoder_opus/build.gradle
index af01cad0137..763eba00b13 100644
--- a/libraries/decoder_opus/build.gradle
+++ b/libraries/decoder_opus/build.gradle
@@ -23,6 +23,14 @@ android {
         }
         androidTest.assets.srcDir '../test_data/src/test/assets'
     }
+
+    // TODO(Internal: b/372449691): Remove packagingOptions once AGP is updated
+    // to version 8.5.1 or higher.
+    packagingOptions {
+        jniLibs {
+            useLegacyPackaging true
+        }
+    }
 }
 
 dependencies {
diff --git a/libraries/decoder_opus/src/main/jni/Android.mk b/libraries/decoder_opus/src/main/jni/Android.mk
index 0b06d9ecd81..676774ed49f 100644
--- a/libraries/decoder_opus/src/main/jni/Android.mk
+++ b/libraries/decoder_opus/src/main/jni/Android.mk
@@ -30,4 +30,6 @@ LOCAL_CPP_EXTENSION := .cc
 LOCAL_SRC_FILES := opus_jni.cc
 LOCAL_LDLIBS := -llog -lz -lm
 LOCAL_STATIC_LIBRARIES := libopus
+# Enable 16 KB ELF alignment.
+LOCAL_LDFLAGS += "-Wl,-z,max-page-size=16384"
 include $(BUILD_SHARED_LIBRARY)
diff --git a/libraries/decoder_vp9/build.gradle b/libraries/decoder_vp9/build.gradle
index d7a29e54277..81dd71500bc 100644
--- a/libraries/decoder_vp9/build.gradle
+++ b/libraries/decoder_vp9/build.gradle
@@ -23,6 +23,14 @@ android {
         }
         androidTest.assets.srcDir '../test_data/src/test/assets'
     }
+
+    // TODO(Internal: b/372449691): Remove packagingOptions once AGP is updated
+    // to version 8.5.1 or higher.
+    packagingOptions {
+        jniLibs {
+            useLegacyPackaging true
+        }
+    }
 }
 
 dependencies {
diff --git a/libraries/decoder_vp9/src/main/jni/Android.mk b/libraries/decoder_vp9/src/main/jni/Android.mk
index cb7571a1b0f..0794feb7308 100644
--- a/libraries/decoder_vp9/src/main/jni/Android.mk
+++ b/libraries/decoder_vp9/src/main/jni/Android.mk
@@ -32,6 +32,8 @@ LOCAL_SRC_FILES := vpx_jni.cc
 LOCAL_LDLIBS := -llog -lz -lm -landroid
 LOCAL_SHARED_LIBRARIES := libvpx
 LOCAL_STATIC_LIBRARIES := cpufeatures
+# Enable 16 KB ELF alignment.
+LOCAL_LDFLAGS += "-Wl,-z,max-page-size=16384"
 include $(BUILD_SHARED_LIBRARY)
 
 $(call import-module,android/cpufeatures)