Youtube 2 mp3

Using youtube-dl and ffmpeg this is a simple script just to get an mp3 file from a youtube URL:

#!/bin/bash
# youtube2mp3
# uses youtube_dl and ffmpeg to get just the mp3 from youtube videos

# By Sebastián Castillo Builes 
# Use this as the community wants in other words obey GPL3+

# Check parameters
if [[ $# != 2 ]]; then 
    echo Usage\: $0 video_url outputfile 
    echo Example\: $0 "\"http://www.youtube.com/watch?v=ewHLy8T2cpA\"" could_be_harder.mp3
    exit 1
fi

# Check dependencies
YOUTUBEDL=$(which youtube-dl)
FFMPEG=$(which ffmpeg)

if ( ( ! [[ -x $YOUTUBEDL ]] ) || (! [[ -x $FFMPEG ]])); then
    echo Error\: You need to install youtube_dl and ffmpeg.
    exit 1
fi

# Everything is ok, so let me see what the video is and where you wanna get the mp3.
URL=$1
OUTPUT=$2

# Temp file to store the video, juste the seconds and nanoseconds in the fiel name to evade collitions.
FLV=/tmp/$(date +%s%N).flv

# OK now go 4 the video and check for errors.
youtube-dl $URL -o $FLV
if [[ $? == 0 ]]; then
    # No errors so suck the mp3 checking 4 errors 2.
    ffmpeg -i $FLV -acodec copy $OUTPUT
    if [[ $? == 0 ]]; then
 # Everything was OK yeah!
 echo
 echo DONE !! now you can listen to $OUTPUT \:\)
 exit 0
    fi
    # Oops ffmpg
    echo 
    echo It seems that you have problems with ffmpeg, try googling the error.
    exit 1
fi
# Oops youtube_dl
echo
echo It seems that you have problems with youtube_dl, maybe is the network conection?, try googling the error.
exit 1