For FFMPEG it will be 3.1.1 & NDK it will be r12b.(How to Build FFmpeg for Android)

ref:
http://stackoverflow.com/questions/36277628/android-how-to-configure-ffmpeg-latest-version-in-android-studio



For FFMPEG it will be 3.1.1 & NDK it will be r12b.

Building FFMPEG with NDK r12b:

Download Android NDK : The latest version of Android NDK can be downloaded at Android NDK website. At the time of writing this answer, the newest version is NDK r12. simply decompress the archive
Download ffmpeg source code : FFMPEG source code can be downloaded from the ffmpeg website. The latest stable release is 3.1.1 (at the time of writing). Download the source code and decompress it to $NDK/sources folder.
Update configure file : Open ffmpeg-3.1.1/configure file with a text editor, and locate the following lines.

SLIBNAME_WITH_MAJOR='$(SLIBNAME).$(LIBMAJOR)'
LIB_INSTALL_EXTRA_CMD='$$(RANLIB) "$(LIBDIR)/$(LIBNAME)"'
SLIB_INSTALL_NAME='$(SLIBNAME_WITH_VERSION)'
SLIB_INSTALL_LINKS='$(SLIBNAME_WITH_MAJOR) $(SLIBNAME)'
This cause ffmpeg shared libraries to be compiled to libavcodec.so. (e.g. libavcodec.so.55), which is not compatible with Android build system. Therefore we’ll need to replace the above lines with the following lines.
SLIBNAME_WITH_MAJOR='$(SLIBPREF)$(FULLNAME)-$(LIBMAJOR)$(SLIBSUF)'
LIB_INSTALL_EXTRA_CMD='$$(RANLIB) "$(LIBDIR)/$(LIBNAME)"'
SLIB_INSTALL_NAME='$(SLIBNAME_WITH_MAJOR)'
SLIB_INSTALL_LINKS='$(SLIBNAME)
Build ffmpeg : Copy the following text to a text editor and save it as build_android.sh in ffmpeg_3.1.1 folder.

#!/bin/bash
NDK=$HOME/Desktop/adt/android-ndk-r9
SYSROOT=$NDK/platforms/android-9/arch-arm/
TOOLCHAIN=$NDK/toolchains/arm-linux-androideabi-4.8/prebuilt/linux-x86_64
function build_one
{
./configure
--prefix=$PREFIX
--enable-shared
--disable-static
--disable-doc
--disable-ffmpeg
--disable-ffplay
--disable-ffprobe
--disable-ffserver
--disable-avdevice
--disable-doc
--disable-symver
--cross-prefix=$TOOLCHAIN/bin/arm-linux-androideabi-
--target-os=linux
--arch=arm
--enable-cross-compile
--sysroot=$SYSROOT
--extra-cflags="-Os -fpic $ADDI_CFLAGS"
--extra-ldflags="$ADDI_LDFLAGS"
$ADDITIONAL_CONFIGURE_FLAG
make clean
make
make install
}
CPU=arm
PREFIX=$(pwd)/android/$CPU
ADDI_CFLAGS="-marm"
build_one
Once the file is saved, go to the directory where this file lies & execute the command below,

sudo chmod +x build_android.sh
Then execute the script by the command,
./build_android.sh
Build Output : The build can take a while to finish depending on your computer speed. Once it’s done, you should be able to find a folder $NDK/sources/ffmpeg-3.1.1/android, which contains arm/lib and arm/include folders.
Make ffmpeg Libraries available for Your Projects
Steps above are fully tested and i performed them on my machine and the build was successful. For writing this answer i have took the reference from this article How to Build ffmpeg with NDK r9 but as it was for older version i have made some corrections on my own.
Open for asking any doubts.