Convert OPUS to AAC

The format has been created by IETF community for online broadcasting and is being used for lossy compression of audio data. It provides with excellent quality of sound and very good compression level due to the technology of dynamically adjusted streaming. Being a key audio codec of Skype, OPUS is based on the Skype message-transfer algorithms. As a container, they use .ogg extension.

The format uses CELT and SILK codecs, which allow easy change of bitrate within the range of 6-510 Kbit/s. That is why it has gained prevalence in video chats and video conferences, as well as IP translations.

A proprietary format with lossy compression, which have been created as an alternative for MP3 with a higher quality of coding. Overtones out of human perception are being removed. AAC is two times less than MP3, which means 1/10 of CD digital data.

The format has being widely used since 1997 as the seventh release of MPEG-2 family. As it is supplied by hardware players, the format is highly demanded by music fans. It has been widely spread in Apple production and is being used by default in iTunes.

The format conception is similar to MP3, but it is more advanced. Being able to execute larger compression, it is represented as a separate segment of MPEG-4 standard which is used for creation of compact audio files. AAC is highly efficient with variable and continuous bitrate, with sampling frequency of 8-96 KHz.

The current version complies with the standard of ISO/IEC 14496-3. Compression is performed on the basis of auditory masking effect that provides with data reduction with no deterioration for sound quality.