Guide to building FFmpeg

GUIDE FOR COMPILING FFMPEG BINARIES FOR ANDROID

• Tested on Mac OS X El Capitan (10.11.6)
• Android NDK R12b
• Android Studio 2.1.2

STEP 0 -- PREREQUISITES

• Download and extract Android NDK
• Download and extract FFmpeg binaries

STEP 1 -- SETTING ENVIRONMENT VARIABLES

We need to add the Android NDK path as an environment variable. Open the Mac Terminal, and:

$ open ~/.bash_profile

In the TextEdit window that opens up:

export ANDROID_NDK=<path-to-your-extracted-ndk>/android-ndk-r12b

STEP 2 -- BUILDING FFMPEG

• Extract the ffmpeg binaries, rename the extracted folder as ffmpeg (if it isn't that already).
• Place them inside the sources folder inside android-ndk-r12b.
• Create a build script and set the configurable options. Here is the script I used.
• Open a Terminal and cd (change directory) to the ffmpeg source directory (easy way) and execute the script (in this case, my script is called ffmpeg_build.sh):

./ffmpeg_build.sh

UNDERSTANDING THE CONFIGURATION OPTIONS:

• Open Terminal and cd to the ffmpeg source directory that you extracted earlier.
• Run:

./configure --help

STEP 3 -- COMPILING FFMPEG

Now that we have built from ffmpeg sources, we need to compile it for Android. Here's how:

• Open Terminal
• cd to the ffmpeg source folder
• Run:

make clean
make -j4
make install

The -j4 command specifies the number of cores that will be utilized. This depends on your system.

ABOUT THE MAKE COMMAND

CMake is a platform-agnostic tool used for managing the build process. The easiest way to get it on your Mac is by getting Homebrew.

STEP 4

You're done! Depending on how you'd written the build script for ffmpeg, you'll find the compiled ffmpeg binaries in the corresponding location. In my case: <path-to-your-extracted-ndk>/android-ndk-r12b/sources/ffmpeg/android/arm/bin.

Just copy the compiled binary file and place it in the assets folder in the ffmpeg Android library (which you either added as a dependency or cloned from this repo).