# Using the MMFI library structure reference

This section provides a reference to the structures used by MMFI functions in the Video Messaging Server Interface. It includes structure definitions and field descriptions.

The following table lists the MMFI structures by function. Only those functions that have associated structures are included in the list.

MMFI function | Associated structures
mmGetFileInfo | FILE_INFO_DESC The following multimedia file presentation block structures: FILE_INFO_BLOCK_HEADER FILE_INFO_PRESENTATION The following multimedia file stream block structures: FILE_INFO_BLOCK_HEADER FILE_INFO_CODEC_AMR FILE_INFO_CODEC_H263 FILE_INFO_CODEC_H264 FILE_INFO_CODEC_MPEG4 FILE_INFO_FORMAT_AUDIO FILE_INFO_FORMAT_VIDEO FILE_INFO_STREAM_HEADER
mmGetVersion | MMFI_VERS_INFO
mmOpenFile | FILE_FORMAT_DESC
mmOpenStream | DATA_FORMAT_DESC DATA_FORMAT_INFO