TagLib is a library for reading and editing the metadata of several popular audio formats. Currently it supports both ID3v1 and ID3v2 for MP3 files, Ogg Vorbis comments and ID3 tags in FLAC, MPC, Speex, WavPack, TrueAudio, WAV, AIFF, MP4, APE, DSF, DFF, and ASF files.
TagLib is distributed under the GNU Lesser General Public License (LGPL) and Mozilla Public License (MPL). Essentially that means that it may be used in proprietary applications, but if changes are made to TagLib they must be contributed back to the project. Please review the licenses if you are considering using TagLib in your project.
** Modification ** TagLib was modified for handling video properties and tags. Please note, many things was derived from taglib-csharp implementation (https://github.com/mono/taglib-sharp), so in case of any issues, please check changes in that repo. Implemented formats: mp4 video, avi, mkv, mpeg-1, mpeg-2, wmv.