Extract Audio from MOV to DSS — Free Online Tool
Extract audio from MOV files and convert it to DSS format using the ADPCM IMA OKI codec — the proprietary compressed audio standard used by Olympus, Philips, and Grundig digital dictation devices. Ideal for workflows that require speech-optimized, low-bitrate audio compatible with professional transcription hardware.
to
FFmpeg Command
Copy this command to run the same conversion locally with FFmpeg on your desktop. Download FFmpeg
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Note: Browser-based encoding uses approximate quality targets. For precise CRF compression, copy the FFmpeg command above and run it on your desktop.
Estimated output:
Conversion Complete!
DownloadHow It Works
During this conversion, FFmpeg discards the video stream entirely from the MOV container and re-encodes the audio — typically AAC or another MOV-compatible codec — into ADPCM IMA OKI, the only audio codec supported by the DSS format. This is a full transcoding operation, not a remux: the audio data is decoded from its original MOV codec and re-encoded using adaptive delta pulse-code modulation tuned for low-bitrate speech. DSS is a proprietary format with a fixed, narrow audio specification designed for voice dictation, so no quality parameters are adjustable — the output bitrate and sample rate are dictated by the format itself. The resulting file is a compact, speech-optimized DSS file compatible with digital dictation recorders and transcription software.
What Each Flag Does
| Flag | What it does |
|---|---|
ffmpeg
|
Invokes the FFmpeg media processing tool. In this browser-based tool, FFmpeg runs entirely via WebAssembly (FFmpeg.wasm) — no data leaves your device. The same command can be run locally on your desktop if you have FFmpeg installed. |
-i input.mov
|
Specifies the input file — a MOV (QuickTime) container that may contain video, audio, chapter markers, and multiple tracks. FFmpeg reads and demuxes this file to access the audio stream for re-encoding. |
-vn
|
Disables video output entirely, telling FFmpeg to ignore all video streams from the MOV file. Since DSS is a voice-only audio format with no video support, this flag ensures only the audio stream is processed. |
-c:a adpcm_ima_oki
|
Sets the audio codec to ADPCM IMA OKI — the only codec used by the DSS format. This re-encodes the MOV audio (typically AAC) using adaptive delta pulse-code modulation at a fixed low bitrate optimized for speech intelligibility on digital dictation devices. |
output.dss
|
Specifies the output filename with the .dss extension, which signals FFmpeg to write a Digital Speech Standard container. The DSS muxer wraps the ADPCM IMA OKI audio stream in the proprietary DSS file structure expected by Olympus, Philips, and Grundig dictation hardware and software. |
Common Use Cases
- Preparing voice memos or interviews recorded on an iPhone (which saves as MOV) for playback or transcription on an Olympus or Philips digital dictation device
- Converting MOV footage of spoken-word content — such as conference presentations or legal depositions — into DSS files for import into professional transcription software like Philips SpeechExec or Olympus Transcription Module
- Archiving dictated content captured on a video camera into DSS format for compatibility with a legacy dictation management system
- Extracting narration audio from a MOV screen recording and converting it to DSS so it can be transcribed using dictation foot pedal hardware
- Batch-preparing MOV audio files from a journalism workflow for delivery to a transcription service that requires DSS input
- Stripping video from MOV field recordings of interviews to produce compact DSS files for storage on digital dictation devices with limited memory
Frequently Asked Questions
Yes — DSS uses the ADPCM IMA OKI codec, which is a lossy, low-bitrate format specifically engineered for intelligible speech rather than high-fidelity audio. If your MOV file contains music, ambient sound, or wide-frequency audio, much of that detail will be lost. For spoken voice content, the quality degradation is acceptable and the resulting file will remain clearly intelligible, which is exactly what DSS was designed for.
No — DSS is a tightly specified proprietary format that does not expose adjustable audio quality parameters through FFmpeg. The ADPCM IMA OKI codec encodes at a fixed rate determined by the format specification. Unlike converting MOV to MP3 or AAC where you can set a target bitrate, DSS output settings are locked. This is why the FFmpeg command for this conversion contains no -b:a or -ar flags.
The video stream is completely discarded. The -vn flag in the FFmpeg command explicitly tells FFmpeg to ignore all video streams in the MOV file and process only the audio. The DSS format has no concept of video — it is a pure audio container for dictation, so no video data is carried through to the output file.
No. MOV is a rich container that supports chapter markers, multiple audio tracks, subtitle streams, and extensive metadata, but DSS supports none of these features. The conversion strips all metadata, chapters, and non-primary audio tracks. Only the first (or primary) audio stream is encoded into the DSS output. If your MOV contains multiple audio tracks, only one will be carried through.
DSS files produced with the ADPCM IMA OKI codec via FFmpeg follow the Digital Speech Standard specification co-developed by Olympus, Philips, and Grundig. In most cases these files will be recognized by dictation and transcription software from those manufacturers, but proprietary DSS implementations sometimes include non-standard header fields or DRM that FFmpeg cannot replicate. It is recommended to test playback on your specific software or device before relying on this workflow for critical content.
On Linux or macOS, you can batch-process files with a shell loop: for f in *.mov; do ffmpeg -i "$f" -vn -c:a adpcm_ima_oki "${f%.mov}.dss"; done. On Windows Command Prompt, use: for %f in (*.mov) do ffmpeg -i "%f" -vn -c:a adpcm_ima_oki "%~nf.dss". This runs the same conversion command against every MOV file in the current directory and outputs a corresponding DSS file for each.
Technical Notes
DSS (Digital Speech Standard) is one of the most constrained audio formats supported by FFmpeg. It uses the ADPCM IMA OKI codec — a variant of Adaptive Delta Pulse-Code Modulation developed by OKI Semiconductor — which operates at a very low bitrate optimized exclusively for the frequency range of human speech (roughly 300–3400 Hz). When converting from MOV, the source audio codec (commonly AAC at 128k or higher) must be fully decoded and re-encoded, meaning this is never a lossless or stream-copy operation regardless of the source quality. MOV files may contain multiple audio tracks; FFmpeg will default to the first audio stream only, as DSS does not support multiple tracks. Transparency, subtitles, chapter markers, and all MOV-specific metadata are silently dropped during conversion. The resulting DSS files are typically very small — often a fraction of the size of the source MOV audio — making them practical for storage on older digital dictation hardware with limited flash memory. Note that some Philips and Olympus devices use a newer DSS Pro (DS2) format which is distinct from DSS and not the same output produced by this command.