最简单的android studio调用ffmpeg动态库

准备工作：

1.编译好的ffmpeg动态库.so文件，以及ffmpeg的头文件；

2.android studio开发环境，包括NDK等可用环境；

步骤一：

新建一个android studio工程，命名netplayer，勾选“Include C++ support”；其他选择默认，直到完成；

步骤二：

将ffmpeg的动态库和include头文件，拷贝到netplayer工程的libs目录下：

android studio会自动更新工程列表，后续主要修改以下几个文件：

//C++接口的实现，内部封装ffmpeg功能

E:\MyAndroidWorkSpace\netplayer\app\src\main\cpp\native-lib.cpp

//java界面，调用C++接口E:\MyAndroidWorkSpace\netplayer\app\src\main\java\player\cn\com\netplayer\MainActivity.java

//编译参数，指定库E:\MyAndroidWorkSpace\netplayer\app\CMakeLists.txt

//jni相关E:\MyAndroidWorkSpace\netplayer\app\build.gradle

步骤三（CMakeList.txt）

cmake_minimum_required(VERSION 3.4.1)find_library( log-lib              log )set(distribution_DIR ../../../../libs)add_library( native-lib             SHARED             src/main/cpp/native-lib.cpp )add_library( avcodec-57             SHARED             IMPORTED)set_target_properties( avcodec-57                       PROPERTIES IMPORTED_LOCATION                       ${distribution_DIR}/armeabi/libavcodec-57.so)add_library( avfilter-6             SHARED             IMPORTED)set_target_properties( avfilter-6                       PROPERTIES IMPORTED_LOCATION                       ${distribution_DIR}/armeabi/libavfilter-6.so)add_library( avformat-57             SHARED             IMPORTED)set_target_properties( avformat-57                       PROPERTIES IMPORTED_LOCATION                       ${distribution_DIR}/armeabi/libavformat-57.so)add_library( avutil-55             SHARED             IMPORTED)set_target_properties( avutil-55                       PROPERTIES IMPORTED_LOCATION                       ${distribution_DIR}/armeabi/libavutil-55.so)add_library( swresample-2             SHARED             IMPORTED)set_target_properties( swresample-2                       PROPERTIES IMPORTED_LOCATION                       ${distribution_DIR}/armeabi/libswresample-2.so)add_library( swscale-4             SHARED             IMPORTED)set_target_properties( swscale-4                       PROPERTIES IMPORTED_LOCATION                       ${distribution_DIR}/armeabi/libswscale-4.so)include_directories(libs/include)target_link_libraries( native-lib                       avcodec-57                       avfilter-6                       avformat-57                       avutil-55                       swresample-2                       swscale-4                       ${log-lib} )

步骤四(build.gradle)：

在系统生成的原来基础上，加入：

defaultConfig下加入：

sourceSets {    main {        jniLibs.srcDirs = ['libs']    }}

externalNativeBuild下加入：
ndk{    abiFilters "armeabi"}

完整内容：
apply plugin: 'com.android.application'android {    compileSdkVersion 25    buildToolsVersion "26.0.0"    defaultConfig {        applicationId "player.cn.com.netplayer"        minSdkVersion 15        targetSdkVersion 25        versionCode 1        versionName "1.0"        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"        sourceSets {            main {                jniLibs.srcDirs = ['libs']            }        }        externalNativeBuild {            cmake {                cppFlags ""            }            ndk{                abiFilters "armeabi"            }        }    }    buildTypes {        release {            minifyEnabled false            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'        }    }    externalNativeBuild {        cmake {            path "CMakeLists.txt"        }    }}dependencies {    compile fileTree(dir: 'libs', include: ['*.jar'])    androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {        exclude group: 'com.android.support', module: 'support-annotations'    })    compile 'com.android.support:appcompat-v7:25.3.1'    compile 'com.android.support.constraint:constraint-layout:1.0.2'    testCompile 'junit:junit:4.12'}

经过以上4个步骤，已经可以build成功了。
步骤5（native-lib.cpp）
#include <jni.h>#include <string>#include <android/log.h>extern "C" {//编码#include "libavcodec/avcodec.h"//封装格式处理#include "libavformat/avformat.h"//像素处理#include "libswscale/swscale.h"}#define FFLOGI(FORMAT,...) __android_log_print(ANDROID_LOG_INFO,"ffmpeg",FORMAT,##__VA_ARGS__);#define FFLOGE(FORMAT,...) __android_log_print(ANDROID_LOG_ERROR,"ffmpeg",FORMAT,##__VA_ARGS__);extern "C"JNIEXPORT jstring JNICALLJava_player_cn_com_netplayer_MainActivity_stringFromJNI(        JNIEnv *env,        jobject /* this */) {    std::string hello = "Hello from C++";    return env->NewStringUTF(hello.c_str());}extern "C"JNIEXPORT jstring JNICALLJava_player_cn_com_netplayer_MainActivity_InitFFMPEG(        JNIEnv* env,        jobject /* this */) {    //1.注册所有组件    av_register_all();    std::string hello = "av_register_all OK";    return env->NewStringUTF(hello.c_str());}

步骤六(MainActivity.java)：

package player.cn.com.netplayer;import android.support.v7.app.AppCompatActivity;import android.os.Bundle;import android.widget.TextView;public class MainActivity extends AppCompatActivity {    // Used to load the 'native-lib' library on application startup.    static {        System.loadLibrary("native-lib");        System.loadLibrary("avcodec-57");        System.loadLibrary("avfilter-6");        System.loadLibrary("avformat-57");        System.loadLibrary("avutil-55");        System.loadLibrary("swresample-2");        System.loadLibrary("swscale-4");    }    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        // Example of a call to a native method        TextView tv = (TextView) findViewById(R.id.sample_text);        tv.setText(stringFromJNI());        tv.setText(InitFFMPEG());    }    /**     * A native method that is implemented by the 'native-lib' native library,     * which is packaged with this application.     */    public native String stringFromJNI();    //初始化ffmpeg库    public native String InitFFMPEG();}

演示结果：

Demo程序下载地址：https://github.com/zhuxian2009/netplayer