#!/bin/bash
download_extract () {
local archive_name="$1"
local download_url="$2"
local archive_type="$3"
shift 3
if [[ ! -e "$archive_name" ]]; then
    wget -nc -O "$archive_name" "$download_url" --no-check-certificate 
    tar -xv"$archive_type"f "$archive_name"
    rm "$archive_name"
fi
}

mkdir src
cd src
download_extract "ffmpeg-3.0.2.tar.bz2" "http://ffmpeg.org/releases/ffmpeg-3.0.2.tar.bz2" "j"
cd ..