Convert M4R to OPUS
Convert your M4R files to OPUS online
M4R: the ringtone file used in Apple iOS
The M4R format is used in Apples mobile devices, mostly for storing ringtones. You can create an M4R file by converting other formats or downloading it from the official iTunes store. The sound conversion employs a special type of compression, which significantly reduces the file size. The advantages of this format make it ideal for iPhone owners. M4R is one of the constituents of the standardized MPEG-4 format. One of its strong points is that the high sound quality is fully preserved after compression.
Opus (formerly Harmony): an audio codec for lossy compression
This format was created for online broadcasting. Opus is an audio codec for compression used on the Internet in real-time mode. Employed by programs such as Skype and Mozilla. Mostly used in interactive applications. The advantages of Opus are high audio quality and good compression. It works only on devices powered by Windows. Opus files can be converted to similar extensions.