（四）AndroidStudio4.1.1下配置FFmpeg

可以创建一个默认的C++的Native工程

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引入依赖 编译好的FFmpeg的so文件

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同时引入编译好后生成的include源码文件

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开始配置CMakeList.txt

• 其实配置很简单：

1.include_directories(include) 这是引入头文件

2. include_directories 和 set_target_properties 是引入对应的so文件，如果编译成一个so文件的话 就不用这么麻烦，一个就搞定（但是在最新版本的NDK 21和FFMpeg4.3.1 下 我不知道如何编译成一个so文件,如果会的可以私信告诉我下）

3.find_library 就是对应上面的配置文件 注意的是：native-lib 要放在最前面

# For more information about using CMake with Android Studio, read the
# documentation: https://d.android.com/studio/projects/add-native-code.html

# Sets the minimum version of CMake required to build the native library.

cmake_minimum_required(VERSION 3.10.2)

# Declares and names the project.

project("test341")
include_directories(include)

add_library(avcodec
        SHARED
        IMPORTED)
set_target_properties(avcodec
        PROPERTIES IMPORTED_LOCATION
        ../../../../libs/armeabi-v7a/libavcodec.so)

add_library(avdevice
        SHARED
        IMPORTED)
set_target_properties(avdevice
        PROPERTIES IMPORTED_LOCATION
        ../../../../libs/armeabi-v7a/libavdevice.so)

add_library(avfilter
        SHARED
        IMPORTED)
set_target_properties(avfilter
        PROPERTIES IMPORTED_LOCATION
        ../../../../libs/armeabi-v7a/libavfilter.so)

add_library(avformat
        SHARED
        IMPORTED)
set_target_properties(avformat
        PROPERTIES IMPORTED_LOCATION
        ../../../../libs/armeabi-v7a/libavformat.so)

add_library(avutil
        SHARED
        IMPORTED)
set_target_properties(avutil
        PROPERTIES IMPORTED_LOCATION
        ../../../../libs/armeabi-v7a/libavutil.so)

add_library(postproc
        SHARED
        IMPORTED)
set_target_properties(postproc
        PROPERTIES IMPORTED_LOCATION
        ../../../../libs/armeabi-v7a/libpostproc.so)

add_library(swresample
        SHARED
        IMPORTED)
set_target_properties(swresample
        PROPERTIES IMPORTED_LOCATION
        ../../../../libs/armeabi-v7a/libswresample.so)

add_library(swscale
        SHARED
        IMPORTED)
set_target_properties(swscale
        PROPERTIES IMPORTED_LOCATION
        ../../../../libs/armeabi-v7a/libswscale.so)

# Creates and names a library, sets it as either STATIC
# or SHARED, and provides the relative paths to its source code.
# You can define multiple libraries, and CMake builds them for you.
# Gradle automatically packages shared libraries with your APK.

add_library( # Sets the name of the library.
        native-lib

        # Sets the library as a shared library.
        SHARED

        # Provides a relative path to your source file(s).
        native-lib.cpp)

# Searches for a specified prebuilt library and stores the path as a
# variable. Because CMake includes system libraries in the search path by
# default, you only need to specify the name of the public NDK library
# you want to add. CMake verifies that the library exists before
# completing its build.

find_library( # Sets the name of the path variable.
        log-lib
        # Specifies the name of the NDK library that
        # you want CMake to locate.
        log)

# Specifies libraries CMake should link to your target library. You
# can link multiple libraries, such as libraries you define in this
# build script, prebuilt third-party libraries, or system libraries.

target_link_libraries( # Specifies the target library.
        native-lib
        avcodec
        avdevice
        avfilter
        avformat
        avutil
        postproc
        swresample
        swscale
        # Links the target library to the log library
        # included in the NDK.
        -landroid
        ${log-lib})

上面的配置是完全ok的，值得注意的是，如果你的CMakeList文件在app目录下 就配置对应的路径就行！

gradle.build配置

plugins {
    id 'com.android.application'
    id 'kotlin-android'
}

android {
    compileSdkVersion 30
    buildToolsVersion "30.0.2"

    defaultConfig {
        applicationId "com.marvel.test341"
        minSdkVersion 23
        targetSdkVersion 30
        versionCode 1
        versionName "1.0"

        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
        externalNativeBuild {
            cmake {
                cppFlags ""
            }
            ndk {
                //选择要添加的对应cpu类型的.so库。
                abiFilters "armeabi-v7a"
                // 还可以添加 'x86', 'x86_64', 'mips', 'mips64'
            }
        }
    }

    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }
    externalNativeBuild {
        cmake {
            path "src/main/cpp/CMakeLists.txt"
            version "3.10.2"
        }
    }
    compileOptions {
        sourceCompatibility JavaVersion.VERSION_1_8
        targetCompatibility JavaVersion.VERSION_1_8
    }
    kotlinOptions {
        jvmTarget = '1.8'
    }
}

dependencies {

    implementation "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version"
    implementation 'androidx.core:core-ktx:1.3.2'
    implementation 'androidx.appcompat:appcompat:1.2.0'
    implementation 'com.google.android.material:material:1.2.1'
    implementation 'androidx.constraintlayout:constraintlayout:2.0.4'
    testImplementation 'junit:junit:4.+'
    androidTestImplementation 'androidx.test.ext:junit:1.1.2'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.3.0'
}

最后是在项目中使用

  companion object {
        // Used to load the 'native-lib' library on application startup.
        init {
            System.loadLibrary("native-lib")
        }
    }

可以看到 这里只是加载native-lib 就行，不像之前需要一一引入例如：avcodec 这类的so文件 其实这些文件 已经在CMakeList已经帮忙引入了，这样一来简化了很多步骤了！
源码：一个so库As中配置使用
源码：多个so库As中配置使用