January 30, 2016, Removing support for two external AAC encoders

We have just removed support for VisualOn AAC encoder (libvo-aacenc) and libaacplus in FFmpeg master.

Even before marking our internal AAC encoder as stable, it was known that libvo-aacenc was of an inferior quality compared to our native one for most samples. However, the VisualOn encoder was used extensively by the Android Open Source Project, and we would like to have a tested-and-true stable option in our code base.

When first committed in 2011, libaacplus filled in the gap of encoding High Efficiency AAC formats (HE-AAC and HE-AACv2), which was not supported by any of the encoders in FFmpeg at that time.

The circumstances for both have changed. After the work spearheaded by Rostislav Pehlivanov and Claudio Freire, the now-stable FFmpeg native AAC encoder is ready to compete with much more mature encoders. The Fraunhofer FDK AAC Codec Library for Android was added in 2012 as the fourth supported external AAC encoder, and the one with the best quality and the most features supported, including HE-AAC and HE-AACv2.

Therefore, we have decided that it is time to remove libvo-aacenc and libaacplus. If you are currently using libvo-aacenc, prepare to transition to the native encoder (aac) when updating to the next version of FFmpeg. In most cases it is as simple as merely swapping the encoder name. If you are currently using libaacplus, start using FDK AAC (libfdk_aac) with an appropriate profile option to select the exact AAC profile that fits your needs. In both cases, you will enjoy an audible quality improvement and as well as fewer licensing headaches.

Enjoy!