/**
* Transcodes audio. Uses ffmpeg: a vast number of formats are supported. A compiled ffmpeg binary
* is provided for Windows and Linux (32bit). If support on another platform is required check the
* <a href="http://www.sauronsoftware.it/projects/jave/manual.php">documentation of JAVE</a> or
* disable transcoding (trough configuration) and perform it manually .
*
* @author Joren Six
*/
public final class AudioTranscoder {
// makes sure no instances of AudioTranscoder are created.
private AudioTranscoder() {};
/** Defines the target codec: signed 16 bit little endian pcm. */
public static final DefaultAttributes TARGET_ENCODING =
DefaultAttributes.valueOf(Configuration.get(ConfKey.transcoded_audio_to));
/**
* Transcode the source file to target using the requested number of channels and sampling rate.
*
* @param source The path of the source file.
* @param target The path of the target file. A stereo stream can be down mixed to a mono stream.
* Converting a mono stream to a stereo stream results in a file with two channels with the
* same data.
* @throws EncoderException If FFMPEG fails to transcode the audio an
* UnsupportedAudioFileException is generated.
* @throws IllegalArgumentException if the source file can not be read or the target file is not
* writable.
*/
public static void transcode(final String source, final String target) throws EncoderException {
transcode(source, target, TARGET_ENCODING.getAttributes());
}
/**
* Transcode the source file to target using the requested number of channels and sampling rate.
*
* @param source The path of the source file.
* @param target The path of the target file.
* @param channels The number of channels target should have. A stereo stream can be down mixed to
* a mono stream. Converting a mono stream to a stereo stream results in a file with two
* channels with the same data.
* @param samplingRate The sampling rate the target file should have;
*/
public static void transcode(
final String source, final String target, final Attributes attributes)
throws EncoderException {
final File sourceFile = new File(source);
final File targetFile = new File(target);
// if transcoding is enabled transcode
if (Configuration.getBoolean(ConfKey.transcode_audio)) {
Transcoder.transcode(sourceFile, targetFile, attributes);
} else {
// if transcoding is disabled: copy the audio
FileUtils.cp(source, target);
}
}
public static boolean transcodingRequired(final String transcodedPath) {
return Transcoder.transcodingRequired(transcodedPath, TARGET_ENCODING.getAttributes());
}
}
public static boolean transcodingRequired(final String transcodedPath) {
return Transcoder.transcodingRequired(transcodedPath, TARGET_ENCODING.getAttributes());
}
/**
* Transcode the source file to target using the requested number of channels and sampling rate.
*
* @param source The path of the source file.
* @param target The path of the target file. A stereo stream can be down mixed to a mono stream.
* Converting a mono stream to a stereo stream results in a file with two channels with the
* same data.
* @throws EncoderException If FFMPEG fails to transcode the audio an
* UnsupportedAudioFileException is generated.
* @throws IllegalArgumentException if the source file can not be read or the target file is not
* writable.
*/
public static void transcode(final String source, final String target) throws EncoderException {
transcode(source, target, TARGET_ENCODING.getAttributes());
}
