         convert: (source, bitrate, target, callback) =>
                 options =
                         cwd: "/tmp/"
-                ffmpeg = child_process.spawn "ffmpeg", ["-i", source, '-vn', '-acodec', 'libmp3lame', '-ab', bitrate, '-y', '-ar', '48000', '-ac', '2', '-loglevel', 'quiet', target], options
+                ffmpeg = child_process.spawn FFMPEG, ["-i", source, '-vn', '-acodec', 'libmp3lame', '-ab', bitrate, '-y', '-ar', '48000', '-ac', '2', '-loglevel', 'quiet', target], options
                 ffmpeg.on 'exit', (code) =>
                         @_conversionDone target, code, callback
 

        convert: (source, bitrate, target, callback) =>
                options =
                        cwd: "/tmp/"
                ffmpeg = child_process.spawn "ffmpeg", ["-i", source, '-vn', '-acodec', 'libvorbis', '-ab', bitrate, '-ar', '48000', '-ac', '2', '-loglevel', 'quiet', '-y', target], options
                ffmpeg.on 'exit', (code) =>
                        @_conversionDone target, code, callback


                @_audioGain target, callback


class OpusConverter extends AudioConverter
        suffix: =>
                return "opus"

        audioType: =>
                return "audio/opus"

        mimeType: =>
                return "audio/ogg"

        _audioGain: (target, callback) =>
                callback null

        convert: (source, bitrate, target, callback) =>
                options =
                        cwd: "/tmp/"
                ffmpeg = child_process.spawn FFMPEG, ["-i", source, '-vn', '-acodec', 'libopus', '-ab', bitrate, '-ar', '48000', '-ac', '2', '-loglevel', 'quiet', '-y', target], options
                ffmpeg.on 'exit', (code) =>
                        @_conversionDone target, code, callback


class VorbisConverter extends AudioConverter
        suffix: =>
                return "ogg"
