• Performance improved from 5 (due to fresh x64 faac) to 30x times (depending on numbers of cores).
• Improved (both speed and quality) of mp3 decoding due to switch to ffmpeg from java decoding.
• Improved tag support according to MP4 specification.
• Added chapters support via MP4v2 project (Thanks to https://github.com/TechSmith for maintaining the fork).
• Added super-fast experimental mode of parallel encoding of MP3 files. (Works well for me).
• Keeping the same bitrate as original files to preserve quality
• Major re-engineering of internal architecture.