Mac OS下为Android Studio编译FFmpeg解码库的详细教程

创建$NDK_DIR/sources/ffmpeg-2.5.3/android/arm/Android.mk文件，内容如下：
要注意其中.so前面的数字应该改成你的ffmpeg版本编译出来的数字。

LOCAL_PATH:= $(call my-dir)
 
 include $(CLEAR_VARS)
LOCAL_MODULE:= libavcodec
LOCAL_SRC_FILES:= lib/libavcodec-56.so
LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/include
include $(PREBUILT_SHARED_LIBRARY)
 
 include $(CLEAR_VARS)
LOCAL_MODULE:= libavformat
LOCAL_SRC_FILES:= lib/libavformat-56.so
LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/include
include $(PREBUILT_SHARED_LIBRARY)
 
 include $(CLEAR_VARS)
LOCAL_MODULE:= libswscale
LOCAL_SRC_FILES:= lib/libswscale-3.so
LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/include
include $(PREBUILT_SHARED_LIBRARY)
 
 include $(CLEAR_VARS)
LOCAL_MODULE:= libavutil
LOCAL_SRC_FILES:= lib/libavutil-54.so
LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/include
include $(PREBUILT_SHARED_LIBRARY)
 
 include $(CLEAR_VARS)
LOCAL_MODULE:= libavfilter
LOCAL_SRC_FILES:= lib/libavfilter-5.so
LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/include
include $(PREBUILT_SHARED_LIBRARY)
 
 include $(CLEAR_VARS)
LOCAL_MODULE:= libswresample
LOCAL_SRC_FILES:= lib/libswresample-1.so
LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/include
include $(PREBUILT_SHARED_LIBRARY)

至此ndk配置完毕，后面是配置Android Studio的部分。

Android Studio部分
Android Studio和Eclipse不太一样，它有一定的自动生成Android.mk并自动搞定JNI的能力。
但目前还并不足以让我们使用起来Ffmpeg库。
因此我们的思路是禁用掉Android Studio自动ndk-build的功能，手动编译我们的C代码达到目的。

首先当然要新建一个Android Studio项目。
我们使用$ROOT_DIR指代项目根目录。

1、Android Studio配置ndk路径
$ROOT_DIR/local.properties原先只配置了sdk。

sdk.dir=/usr/local/bin/android-sdk-macosx

给它增加一行ndk的配置

sdk.dir=/usr/local/bin/android-sdk-macosx
ndk.dir=/usr/local/bin/android-ndk-r10d

2、配置build.gradle
项目里面有两个build.gradle，一个在根目录下，一个在$ROOT_DIR/app/src下，我们要修改的是后者。