Converting .mid audio to .mp4 format.
Converting MIDI Files directly to MPEG-4 Videos (.mid to .mp4 conversion) should be possible and straightforward. It relates to users attempting to encode MID audio to MP4 video.
Try using a media editing software or (online) conversion tool, such as the VideoPad Video Editor, which should allow users to import MID audio and export it in MP4 format.
A video editing software for Windows