stainless-ffmpeg-sys 4.2.3

# stainless-ffmpeg-sys
[![Build Status](https://travis-ci.org/media-io/rust-ffmpeg-sys.svg?branch=master)](https://travis-ci.org/media-io/rust-ffmpeg-sys)  
FFmpeg bindings for Rust.

A fork of rust-ffmpeg-sys to manage our FFMpeg version.  
This project is used in stainless-ffmpeg to provide an easiest way to launch ffmpeg.