To produce native libraries that can run on the largest possible number of Linux installations out there, it is recommended to build under CentOS 7. This is because it relies on an old enough version of glibc, which nevertheless works for all the libraries found in the JavaCPP Presets, and since newer versions of glibc are backward compatible, all recent distributions of Linux should support the binaries generated. We do not actually need to install CentOS 7 though. Pretty much any recent distribution of Linux comes with a package for [Docker](https://www.docker.com/). It is also possible to map existing directories, for example `/usr/local/lib/bazel` and `/usr/local/cuda` as shown in the steps below, to reuse an existing [Bazel](http://bazel.io/docs/install.html) or [CUDA](https://developer.nvidia.com/cuda-downloads) installation as well as any other set of files for the purpose of the build.
### Preparations
1. Install Docker under, for example, Fedora and Ubuntu, respectively:
```bash
$ sudo yum install docker
$ sudo apt-get install docker.io
```
2. When using SELinux, it might also be necessary to disable temporarily the firewall, for example:
```
$ sudo systemctl stop firewalld
$ sudo systemctl start docker
```
3. Start the container for CentOS 7 (the command might be `docker.io` instead of `docker`):
OS X Mavericks (10.9) is the first version of Mac OS X to support C++11 fully and properly, so to preserve your sanity, we do not recommend trying to build or use the JavaCPP Presets on any older versions of Mac OS X.
### Preparations
1. Install [Xcode](https://developer.apple.com/xcode/) and [Homebrew](http://brew.sh/)
2. Ensure the command line tools for Xcode are installed
```bash
$ xcode-select --install
```
3. Run the following commands to install the JDK, among other things Apple left out of Xcode:
Visual Studio Community 2013 is the first free version to have been decently bundled with support for C++11, OpenMP, the Windows SDK, and everything else from Microsoft, so we recommend installing that version of Visual Studio, which consequently requires Windows 7. Still, to run the bash scripts and compile some things that the Microsoft C/C++ Compiler does not support, we need to install manually a few other things.
### Preparations
1. Install the [Java SE Development Kit](http://www.oracle.com/technetwork/java/javase/downloads/), [Maven](https://maven.apache.org/download.cgi), [MSYS2](https://msys2.github.io/), [Visual Studio Community 2013](https://www.visualstudio.com/en-us/news/vs2013-community-vs.aspx), and [CUDA](https://developer.nvidia.com/cuda-downloads)
2. Under an "MSYS2 Shell", run:
```bash
$ pacman -S base-devel tar patch make git unzip zip nasm yasm pkg-config mingw-w64-x86_64-cmake mingw-w64-x86_64-gcc mingw-w64-i686-gcc mingw-w64-x86_64-gcc-fortran mingw-w64-i686-gcc-fortran mingw-w64-x86_64-libwinpthread-git mingw-w64-i686-libwinpthread-git
```
3. From the "Visual Studio Tools" found inside the Start menu, open:
- "VS2013 x86 Native Tools Command Prompt" and run `c:\msys64\mingw32_shell.bat` inside
- "VS2013 x64 Native Tools Command Prompt" and run `c:\msys64\mingw64_shell.bat` inside
- Making sure the `set MSYS2_PATH_TYPE=inherit` line is *not* commented out in either of those batch files.
4. Run the "Prerequisites for all platforms" tasks inside the shell
5. Checkout `https://github.com/bigbluebutton/javacpp-presets` and use branch `min-build-1.2-svc2`
6. cd to `javacpp-presets/ffmpeg`
7. If you want to build SVC2 libraries, you copy `cppbuild.sh.svc2` to `cppbuild.sh`
8. After which the following commands inside the `ffmpeg` dir:
where `windows-xxx` is either `windows-x86` or `windows-x86_64`. Run the builds for `windows-x86` inside the "MINGW32" window, and the ones for `windows-x86_64` in the "MINGW64" one.
