Convert RIFF MIDI (.rmi) to Free Lossless Audio Codec (.flac) online for free. Fast, secure audio conversion with no watermarks or registration.
Upload your .rmi file by dragging it into the upload area or clicking to browse.
Choose your output settings. The default settings work great for most files.
Click Convert and download your .flac file when it's ready.
RMI (RIFF MIDI) stores Standard MIDI File data inside Microsoft's RIFF container framework, the binary structure that underpins Windows multimedia. The RIFF wrapper adds metadata storage (INFO chunks for title, artist, copyright) and structural compatibility with Windows multimedia APIs like MCI and DirectMusic. RMI was the format processed by midiOutLongMsg and midiStreamOut calls in the Windows MME subsystem throughout the Windows 95 through Windows XP era.
FLAC (Free Lossless Audio Codec) is the open-source standard for lossless audio compression, achieving 50-60% size reduction without discarding any audio data. Converting RMI to FLAC extracts MIDI from the Windows RIFF container, synthesizes audio through a SoundFont engine, and losslessly compresses the result. This is the ideal archival format for preserving Windows-era MIDI content with zero quality loss.
RMI files are inaccessible outside Windows — the RIFF MIDI container is not recognized by any non-Microsoft audio framework. FLAC provides a universal lossless format that works on Windows, macOS, Linux, Android, and most web browsers. For archiving legacy Windows multimedia content, FLAC preserves maximum synthesis fidelity with broad cross-platform support.
FLAC is also the preferred lossless format for music libraries, media servers (Plex, Jellyfin), and professional audio workflows on non-Apple platforms. Converting RMI to FLAC makes legacy Windows MIDI content accessible to modern media management infrastructure without any quality compromise.
FFmpeg parses the 12-byte RIFF header, validates the RMID form type, and extracts the embedded MIDI data chunk. The MIDI event stream is processed through a software synthesizer loaded with a General MIDI SoundFont — note-on events trigger velocity-scaled sample playback, program changes select instrument patches, and controllers adjust volume, pan, expression, and sustain. The synthesized stereo PCM is encoded using the FLAC codec with linear prediction, residual computation, and Rice entropy coding. Compression level (0-12) trades encoding speed for file size with no quality difference.
FLAC encoding is mathematically lossless — the decoded PCM is bit-identical to the encoder input. Quality is determined solely by the SoundFont and synthesis engine. A premium SoundFont with multi-velocity samples produces natural-sounding results; the default General MIDI bank sounds functional but synthetic. FLAC typically compresses synthesized MIDI audio to 50-65% of raw PCM size — synthesized content often compresses well because it lacks the random noise floor present in microphone recordings.
| Device | RMI | FLAC |
|---|---|---|
| Windows PC | Partial | Partial |
| macOS | Partial | Partial |
| iPhone/iPad | Partial | Partial |
| Android | Partial | Native |
| Linux | Partial | Native |
| Web Browser | No |
Resolution: N/A
Bitrate: 320 kbps
OGG Vorbis preferred
Resolution: N/A
Bitrate: 256 kbps
AAC format required
Resolution: N/A
Bitrate: 128 kbps
Lossless FLAC/WAV for best quality
Resolution: N/A
Bitrate: 128 kbps
MP3 mono for spoken word
RMI to FLAC converts Windows-specific RIFF MIDI into the universal lossless audio format. For archiving legacy Windows multimedia content, FLAC provides zero-loss preservation with cross-platform compatibility.
Saker overforing
HTTPS-krypterade uppladdningar
Integritet forst
Filer raderas automatiskt efter bearbetning
Ingen registrering
Borja konvertera direkt
Fungerar overallt
Valfri webblasare, valfri enhet
| No |
| Funktion | RMI | FLAC |
|---|---|---|
| Fullstandigt namn | RIFF MIDI | Free Lossless Audio Codec |
| Filandelse | .rmi | .flac |
| Bast for | RIFF container | Lossless compression |