XMF stands for Extensible Music Format. It is a file format that consists of single or multiple files like Standard MIDI Files, WAV files, Downloadable Sound (DLS) instrument files or digital audio files, etc. It generates a compilation of all the resources used to represent a piece of music. It is a tree-structured container format. It is a popular choice for mobile phone content via Mobile XMF file type. The specifications for the XMF were first published by the MIDI Manufacturers Association (MMA) in 2001.
- XMF files are made up of a header chunk and a collection of node chunks ordered in preorder.
- Resources can be shown in various languages depending on the country of preference.
- There are currently five XMF Files namely XMF Type 0, XMF Type 1, XMF Type 2, XMF Type 3 and XMF Type 4.
- The XMF File Type 4 is also known as Interactive XMF (iXMF) is the latest one.
- ZLIB is used for compressing the resources in the XMF files.
- It is an extensible format that aims in minimizing overhead, code size, and data size.
- XMF files can be referenced internally as well as externally using a Uniform Resource Identifier (URI).
- It can support an infinite number of quantities as the size information for the XMF files is stored as variable-length quantities (VLQ). This also saves storage space.
- It has no maximum file size.
- Resources in an XMF format can be arranged as per the user’s choice of hierarchy like files and folders in a file system.
- Custom resource types and metadata can be added easily to the XMF file.
- Data-compression or encryption techniques can be decided by the users.
- It is not an optimal method to store musical data.
- It involves nesting of media contents inside exclusive folder nodes that can easily be put directly under the root node.
- Some mobile players can get choked due to the excessive amounts of nodes present in the format.