MKV is an open container format for audio and video data created by Russian developers. The name of the format originates from the name of the project - Matroska (Matryoshka) with the addition of the first letter of the word Video. This format is considered an alternative to the much more popular AVI, but has not yet reached such a scale of distribution. MKV files are quite common among owners of fairly old mobile devices with Symbian OS and at the same time among those who prefer to watch video in FullHD, since MKV has good dynamics of transmitting video / audio streams. MKV with a wide range of features, in particular, storing audio tracks in different languages, is easy to edit, there are no freezes in large files.
MMF is the Yamaha SMAF sound file format developed for mobile devices. The MMF format is linked to SMAF (Synthetic Music Mobile Application Format) files. Many people know this format because they very often use it as ringtones in cell phones. Yamaha’s SMAF tools were developed primarily by Yamaha to provide audio files that users could use as unique ringtones for their mobile phones. However, then the format was slightly improved. Now such files are capable of storing information, graphic, as well as text. You can create an SMAF file using Yamaha SMAF Tools. It can also be saved in WAV or MID format. It’s not uncommon to confuse MMF and SMAF formats. The fact is that MMF are called file extensions. SMAF is called the file itself. The MMF file is identical to MIDI files. It is capable of supporting music playback and showing graphics. Due to the implementation of the image display function, SMAF files now have considerable potential in the mobile application market. This is because they can store high quality images when the file size is limited at the same time. Typically, the size of SMAF files is much smaller than files of other formats that can perform the same functions.