public static boolean isTranscodeRequired(TranscodeProfile profile, AudioStream stream) {
// Check audio codec
if (getAudioChannelCount(stream.getConfiguration()) > 2) {
if (profile.getMchCodecs() == null
|| !isSupported(profile.getMchCodecs(), stream.getCodec())) {
return true;
}
} else {
if (!isSupported(profile.getCodecs(), stream.getCodec())) {
return true;
}
}
// Check audio sample rate
if (stream.getSampleRate() > profile.getMaxSampleRate()) {
return true;
}
// If direct play is not enabled check stream parameters
if (!profile.isDirectPlayEnabled()) {
// Check bitrate for audio elements
if (profile.getMediaElement().getType() == MediaElementType.AUDIO) {
int bitrate =
(getAudioChannelCount(stream.getConfiguration())
* AUDIO_QUALITY_MAX_BITRATE[profile.getQuality()]);
if (bitrate > 0 && profile.getMediaElement().getBitrate() > bitrate) {
return true;
}
}
}
return false;
}
public static boolean processAudio(TranscodeProfile profile) {
// Check variables
if (profile.getMediaElement() == null
|| profile.getCodecs() == null
|| profile.getQuality() == null) {
return false;
}
// If there are no audio streams to process we are done
if (profile.getMediaElement().getAudioStreams() == null) {
return true;
}
// Set audio track if necessary
if (profile.getAudioTrack() == null) {
if (profile.getMediaElement().getAudioStreams().size() > 0) {
profile.setAudioTrack(0);
} else {
return true;
}
}
// Check a format is specified for video transcode
if (profile.getMediaElement().getType() == MediaElementType.VIDEO
&& profile.getFormat() == null) {
return false;
}
// Process each audio stream
List<AudioTranscode> transcodes = new ArrayList<>();
for (AudioStream stream : profile.getMediaElement().getAudioStreams()) {
String codec = null;
Integer quality = null;
Integer sampleRate = null;
boolean downmix = false;
// Check if transcoding is required
boolean transcodeRequired = isTranscodeRequired(profile, stream);
// Check the format supports this codec for video or that we can stream this codec for audio
if (!transcodeRequired) {
if (profile.getFormat() != null) {
transcodeRequired =
!isSupported(getCodecsForFormat(profile.getFormat()), stream.getCodec());
} else {
transcodeRequired = !isSupported(TRANSCODE_AUDIO_CODECS, stream.getCodec());
}
}
if (!transcodeRequired) {
// Work around transcoder bug where flac files have the wrong duration if the stream is
// copied
codec = "copy";
// Get format if required
if (profile.getFormat() == null) {
profile.setFormat(getFormatForAudioCodec(stream.getCodec()));
}
} else {
// Test if lossless codecs should be prioritised
if (profile.getMediaElement().getType() == MediaElementType.AUDIO
&& (profile.getQuality() == AudioQuality.LOSSLESS || profile.isDirectPlayEnabled())
&& isSupported(LOSSLESS_CODECS, stream.getCodec())) {
profile.setCodecs(sortStringList(profile.getCodecs(), LOSSLESS_CODECS));
if (profile.mchCodecs != null) {
profile.setMchCodecs(sortStringList(profile.getMchCodecs(), LOSSLESS_CODECS));
}
}
// Check for multichannel codecs if this is a multichannel stream
if (getAudioChannelCount(stream.getConfiguration()) > 2) {
// Try to get a suitable multichannel codec
if (profile.getMchCodecs() != null) {
for (String test : profile.getMchCodecs()) {
if (isSupported(TRANSCODE_AUDIO_CODECS, test)) {
if (profile.getFormat() != null) {
if (isSupported(getCodecsForFormat(profile.getFormat()), test)) {
codec = test;
break;
}
} else {
codec = test;
break;
}
}
}
}
// If a codec couldn't be found we need to downmix to stereo
if (codec == null) {
downmix = true;
}
}
// If we still don't have a codec just try anything...
if (codec == null) {
for (String test : profile.getCodecs()) {
if (isSupported(TRANSCODE_AUDIO_CODECS, test)) {
if (profile.getFormat() != null) {
if (isSupported(getCodecsForFormat(profile.getFormat()), test)) {
codec = test;
break;
}
} else {
codec = test;
break;
}
}
}
}
// Check audio parameters for codec
if (codec != null) {
// Sample rate
if ((stream.getSampleRate() > profile.getMaxSampleRate())
|| (stream.getSampleRate() > getMaxSampleRateForCodec(codec))) {
sampleRate =
(profile.getMaxSampleRate() > getMaxSampleRateForCodec(codec))
? getMaxSampleRateForCodec(codec)
: profile.getMaxSampleRate();
}
// Quality
if (profile.getMediaElement().getType() == MediaElementType.AUDIO) {
quality = getAudioQualityForCodec(codec, profile.getQuality());
} else if (profile.getMediaElement().getType() == MediaElementType.VIDEO) {
quality =
getAudioQualityForCodec(codec, VIDEO_QUALITY_AUDIO_QUALITY[profile.getQuality()]);
}
// Get format if required
if (profile.getFormat() == null) {
profile.setFormat(getFormatForAudioCodec(codec));
}
// Update codec
codec = getEncoderForAudioCodec(codec);
}
}
// Add transcode properties to array
transcodes.add(new AudioTranscode(codec, quality, sampleRate, downmix));
}
// Update profile with audio transcode properties
profile.setAudioTranscodes(transcodes.toArray(new AudioTranscode[transcodes.size()]));
return true;
}