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.
ASF is a media file format developed by Microsoft. This format is preferred for Windows Media. This player can play not only video or audio files, but also mixed recordings that are compressed using certain codecs and saved in an ASF file. Files of this format also additionally store metadata (including title, author, copyright information). The full original name of the format is Advanced Systems Format. The main goal of Microsoft in developing this format was to provide streaming media playback.