M4R is a filename extension for AAC format, which is developed by Apple Inc. It is typically used to save custom iPhone ringtones from Apple iTunes. M4R can only be created from iTunes purchased songs and is usually DRM protected. It can open on iTunes, VLC Media Player, Apple QuickTime Player, and more.
A file with a .trp filename extension is an HD (High Definition) video file that uses MPEG-2 compression. TRP files are typically used to synchronize audio and video codecs in DVB (Digital Video Broadcasting). The video codec is usually H.264, whereas audio data comes in AC3 format. This makes the TRP format to be supported by most media player programs.