Tag Archives: audio book

Splitting Large Audio Books

I’m big fan of audio books.   During past years I’ve been using setup described in this article (libresonic server, android client, audio encoded with opus codec) for audio books listening.  It works well  for me , but it’s best with audio books split to chapters or to parts not longer then 1 hour. However some audio books come in  one large file (m4b format, or  aax proprietary file  from Audible).  To listen to such audio books conveniently I need to split them. Luckily with ffmpeg tool and a bit of bash scripting it is not difficult. Continue reading Splitting Large Audio Books

Opus Audio Codec for Audio Books And More

Opus is a relatively new lossy audio codec from Xiph Foundation, successor to Vorbis and Speex codecs.  It provides very good quality for low bandwidth (<=32kbps) streams with speech, but also provides high quality for broader bandwidth (>64kbps) and more demanding data like music etc.  So it can be one-off solution for any digital audio encoding.  According to some tests presented on it’s site, it’s comparable with HE AAC for higher bandwidth, higher quality data,  while it additionally  provides better results for lower bandwidth, speech data  this is something xHE ACC is addressing too, however I have not seen available codec yet.).  And what is most appealing on Opus is that it’s free, without patents and it’s open source.  (While majority of common audio codecs e.g MP3, AAC are restricted by patents and are subject to paying loyalties , I think Fraunhofer holds basic patents, but situations is quite complex and differs per country).

Based on positives reviews, I though that Opus could be ideal codec for audio books, where it can provide good quality at low bit rates. At least for me, I really do not need top quality for audio books  (say mp3 320kbps), while the book takes gigabytes of space, but on the other hand,  I do appreciate good quality and with low quality audios I have problems to understand them and I cannot really enjoy the book.

So how can Opus help and is it ready for everyday use? Continue reading Opus Audio Codec for Audio Books And More