無料オンラインMP4からOPUSへのコンバーター

MP4 is an extension defined by MPEG-4 video standard and AAC audio standard. It is a container that supports all kinds of media such as video, audio, subtitles, 2D and 3D graphics. It is possible to open MP4 file with almost any player on Windows but on Mac you should use a plug-in or just convert the file to another format.

Opus is a lossy audio coding format developed by the Xiph.Org Foundation and standardized by the Internet Engineering Task Force, designed to efficiently code speech and general audio in a single format, while remaining low-latency enough for real-time interactive communication and low-complexity enough for low-end ARM3 processors. Opus replaces both Vorbis and Speex for new applications, and several blind listening tests have ranked it higher-quality than any other standard audio format at any given bitrate until transparency is reached, including MP3, AAC, and HE-AAC.