I've looked for references on the Audible format, and it appears that people are only interested in cracking/converting out of it. I've got a collection of MP3 files that I want to convert into Audible format for use on my Kindle and iPod.
Does anybody have a good reference on the Audible or protected AAC formats and how section markers and metadata are expressed? Better yet, a utility or code sample?
The Audible format is a DRM protected proprietary format only available from Audible. They protect their format diligently. From what I understood, they used to charge handsomely for the right to use it. I am not aware of any publicly available encoders that will create audible formatted files (for free or not). Since Amazon bought Audible I am not sure if they would even sell the right to anyone else anymore.
I do not own a Kindle, but from what I can tell, it only supports Audible formatted files with full audiobook functionality. MP3's can be played , but they are not treated the same way (no support for chapters etc).
Creating audiobooks with chapter support for the iPod requires creating a M4B file with a text track and making sure the audio track has the proper track reference to the text track. M4B is a version of MP4 that uses AAC audio. There are several programs to do this on the MAC and recently a few have surfaced for the PC.
I have created a freeware software package with a Graphical User Interface (GUI) for the PC which is in Beta test now. It is called "Chapter and Verse" and it will be available on lodensoftware.com shortly. Two other options with GUI's are: "Chapter Master" from Rightword Enterprises ($15) and "iPod Audio Book Converter" (freeware) from sjhaley.com which is in Beta test as well.
Several command line utilities exist as well. One is called Slide Show Assembler (SSA) that can be used to create podcasts as well as audiobooks. SSA is available from jrlearnsmedia.com. Another is a command line utility for manipulating MP4 files called mp4creator. mp4creator can add chapters to a MP4 file.
check out the link
http://podfilecreator.appspot.com
for creating pod files for use in ssa to create audio books.
I struggled with the problem of mp3 to m4b audiobooks on OSX for a while and came up with my workflow.. now summed up in a ruby script that does it all automatically. Here's the workflow:
1.(ruby) sort files and identify chapter names (regexp magic!)
2.(lame) convert all the mp3 to 64kbits mono cbr (this is done to leverage the input files, remove tags that could cause problems in merging, and most of all because coreaudio aac conversion from stereo to mono sucks..)
3.(mp3info ruby gem) compute files length and generate chapter xml file (length computed on the mono cbr version to avoid problems)
4.(cat) merge them
5.(afconvert) convert to aac
6.(ChapterTool) applay chapter markers and rename to m4b
FYI
Chapter and Verse has been released for some time.
The latest version (v1.3) is now available with full capability to create chapterized audiobooks with chapter images for the iPod, iTunes and quicktime.
The program is freeware and is available at lodensoftware.com